CPACS root element
Version
V3.5
Date
2023-12-19
1. Overview
The Common
Parametric
Aircraft
Configuration
Scheme
(CPACS) is an XML-based data format for describing aircraft configurations and their corresponding data.
This XML-Schema document (XSD) serves two purposes:
(1) it defines the CPACS data structure used in the XML file (e.g., aircraft.xml) and
(2) it provides the corresponding documentation (see picture below).
An XML processor (e.g.,
TiXI
https://github.com/DLR-SC/tixi
or XML tools in Eclipse) parses the XSD and XML files and validates whether the data set defined by the user (or tool) conforms to the given structure defined by the schema.
This documentation explains the elements defined in CPACS and its corresponding data types.
Data types can either be simple types (string, double, boolean, etc.) or complex types (definition of attributes and sub-elements to build a hierarchical structure).
In addition, the sequence of the elements and their occurrence is documented.
To link the XML file to the XSD file, the header of the XML file should specify the path of the schema file.
An example could look like this:
]]>
CPACS is an open source project published by the
German Aerospace Center (DLR e.V.)
https://www.dlr.de/
. For further information please visit
www.cpacs.de
https://www.cpacs.de
.
2. Data structure
CPACS data is modeled in a hierarchical structure whose underlying concept follows a top-down description of a system-of-systems which decomposes a generic concept
(e.g., an aircraft or rotorcraft) into a more detailed description of its components.
This originates from the conceptual and preliminary design of aircraft, where the level of detail is initially low and continues to increase as the design process progresses.
For some concepts within CPACS, however, a bottom-up approach is applied where the components are first defined in detail (sometimes referred to as library) and then linked within an instantiated higher-level concept.
This is advantageous when used multiple times within complex systems, such as engines, which only have to be defined once in order to be referenced several times on the aircraft.
The combination of these two methodologies is known as middle-out approach and enables the goal to fully parametrize aeronautical systems.
3. Coordinate Systems
3.1. CPACS coordinate system
Coordinate systems are a regular cause for ambiguous interpretation of data.
In CPACS, the reference coordinate system is the CPACS-coordinate system.
This coordinate system is used for most of the data.
A single exception is made in order to keep aerodynamic data in an aerodynamic coordinate system.
The following paragraphs outline the determination to known coordinate systems.
The CPACS coordinate system is the coordinate system identified by
TiGL
https://dlr-sc.github.io/tigl
, CPACS's geometry library.
It is a right-handed coordinate system. If an aircraft is defined in the CPACS coordinate system it will usually follow the directions listed in the table below.
Therefore, the CPACS coordinate system can be confused with the body-fixed coordinate system.
While often the CPACS coordinate system and the body-fixed coordinate system overlap, this must not always be true.
Several definitions for body-fixed coordinate systems exist (x-axis through nose and tail, x-axis perpendicular to nose plane).
For non-symmetric aircraft, body-fixed coordinate systems become even more complicated.
Hence, analysis tools should stick to the CPACS coordinate system.
It remains to the designer to model the geometry accordingly.
The CPACS coordinate system does not rotate with flow.
Hence, aerodynamic calculations do rotate their flow relative to the CPACS coordinate system.
If not stated explicitly different, e.g. for target lift-coefficients, results are returned in the CPACS coordinate system, i.e. the cfx-coefficient is parallel to the CPACS x-coordinate, regardless of the way the geometry is defined.
The following table gives a "best-practice" advice on how to locate a geometry within CPACS.
Different approaches are, of course, valid as well.
Axis
Direction
Description
x
tailwards
from nose to tail
y
spanwise
from symmetry plane to the right wingtip
z
upwards
from landing gear to tip of vertical tailplane
The following figures show an example of a geometry that is aligned with the CPACS coordinate system, i.e. the body-fixed coordinate system corresponds to the CPACS coordinate system.
The aerodynamic analysis is relative to the CPACS coordinate system.
That is, the angle of attack is represented by the dashed orange line.
Results of the aerodynamic calculation are given in the CPACS coordinate system.
The following figures give an example of a geometry that is not defined in alignment with the CPACS coordinate system.
It is a valid CPACS file, but only used in this example for demonstrative purposes.
The body axes and the CPACS coordinate system do not align.
That is, the origin of the geometry is not at CPACS (0,0,0) but at a point in positive x- and z-direction.
Again, the aerodynamic analysis is relative to the CPACS coordinate system.
That is, the angle of attack is represented by the dashed orange line.
Results of the aerodynamic calculation are given in the CPACS coordinate system.
3.2. Local coordinate systems via parentUID and transformation
Some elements in CPACS, in particular the geometric components, are described in local coordinates.
The hierarchical data structure allows to define a local coordinate system either with respect to the coordinate system of the parent element or with respect to the global CPACS coordinate system.
This is achieved by combining the two elements <parentUID> and <transformation>:
parentUID: An individual data hierarchy can be set up using the optional <parentUID> element.
Here it is important that exactly one element does not contain the <parentUID>
in order to identify the top element of this user-specific hierarchy.
As soon as the parentUID (which refers to the uID of the parent element) is set, a local coordinate system of the corresponding node is instantiated.
transformation: This allows the coordinate system to be transformed via
<translation>,
<rotation> and
<scaling>.
As soon as the <parentUID> is set, this transformation refers to the local coordinate system (in the current CPACS version this only affects <translation>).
An attribute refType is used to either make this explicit (refType="absLocal") or to override this and reference the global CPACS coordinate system instead (refType="absGlobal").
The following table summarizes the possible combinations of <parentUID> and <transformation> and the resulting coordinate system (local or global):
<parentUID> not set
<parentUID> set
<transformation> without refType
global
local
<transformation> with refType="absLocal"
global
local
<transformation> with refType="absGlobal"
global
global
Note:
The combination of <transformation> with refType="absLocal" and no <parentUID> is global,
because the local coordinate system to which the transformation is referring to via refType equals the global coordinate system (see fuselage in the following example).
An exemplary use case further illustrates the concept of the coordinate system hierarchy.
The CPACS schema shall not specify in advance that a wing is always be part of the fuselage and engines must always be part of the wing.
In other cases the engine could be attached to the fuselage, which would not be possible via a predefined XML tree.
The following figure shows how components of the aircraft are related to each other via the <parentUID>.
The fairing is a child of the wing and is therefore automatically translated when the wing is translated.
Likewise, the horizontal tailplane is a part of the vertical tailplane and is therefore affected by translation of the latter:
4. Units
There are no explicit attributes describing units in CPACS.
The general convention is that all values must be given in the following SI-units:
[m]
Position, Distance
[m2]
Area
[m3]
Volume
[kg]
Mass
[s]
Time
[K]
Temperature
or in derived units, e.g.:
[N]
Force
[Nm]
Moment
[W]
Power
[J]
Energy
The only non SI unit used throughout CPACS is the angle in degrees [°].
For the sake of an intuitive use the angles are given in degrees rather than in radian [rad].
[°]
Angle
5. Splitting up a CPACS dataset into several files
To provide a better overview, it is possible to split up a CPACS dataset into several files.
This can be done by inserting an <externaldata> node at an arbitrary position into the dataset.
This node contains a <path> node with a URI to the external file(s), followed by one or more <filename> nodes, containing each a name of a file to be included at that position.
Below, an example of such external data is given:
file:://airfoils
NACA0010.xml
NACA2412.xml
NACA 0012 Airfoil
...
]]>
Such an external file would look like:
NACA 0010 Airfoil
...
]]>
The file would be included completely, except for its title line <?xml version="1.0" encoding="utf-8"?>.
This concept can also be used recursively (external files of external files), but it is important to prevent circle connections (file "A" loading file "B" loading file "C" loading again file "A" ...).
For path URI addresses, the trailing file separator "/" may be omitted. Below, some examples for path URIs are given:
Absolute local path:
file:///tmp or file:///c:/windows/tmp
Relative local directory:
file://relativeDirectory or file://../anotherRelativeDirectory
Remote net resource:
http://www.someurl.de
With the help of the TiXI XML Interface
TiXI
https://github.com/DLR-SC/tixi
, a CPACS dataset that is split into multiple files can be reassembled into a single tree structure for subsequent validation against the CPACS schema.
The following commands are used to link external data sets:
externalFileName:
Name of the external data file
externalDataDirectory:
Directory of the external data file. Its content is analogous to the <externaldata/path> element described above.
externalDataNodePath:
XPath
https://www.w3schools.com/xml/xpath_intro.asp
of the node which is replaced with the content of the external file.
In case that it is an external file of an external file, then it is the XPath in the outer external file.
If, e.g., in the example above the <pointList> element would have also been loaded from an external file, then the entry would just be:externalDataNodePath="/airfoil".
This is used primarily for loop-detection.
The merged data tree for the example above would look like:
NACA 0010 Airfoil
...
...
NACA 0012 Airfoil
...
]]>
6. UIDs and references
The CPACS-dataset often uses references between nodes.
Typically, these references define connections between elements which are located somewhere else in the hierarchical dataset (e.g. a <wing> is connected to a <fuselage>;
a specific <engine> is connected to a <pylon>; etc.).
These connections are defined by unique identifiers (uID) which are specified as attributes.
Thus, there are elements which can be referenced via a uID attribute, e.g. a fuselage:
...
]]>
as well as elements which refer to the former, e.g. a wing pointing to its geometrical parent:
ATTAS main wing
ATTAS_fuselage
...
]]>
In previous CPACS versions, referencing elements were identified via the isLink="True" attribute.
Since this is superfluous due to the explicit definition of the element properties via the CPACS schema, this attribute no longer needs to be listed.
It is nevertheless a valid optional attribute to ensure compatibility with older datasets, but might be removed in future versions.
Since uIDs are only used to link nodes within the XML file, no naming convention is required.
The characters only have to conform to the conventions of the
xsd:ID
http://books.xmlschemata.org/relaxng/ch19-77151.html
type standardized by the
W3C
https://www.w3.org/
.
UIDs, however, must be unique!
Although a common practice for naming uIDs is their position in the data hierarchy (e.g. uID="mainWingSection3"), uIDs as shown in the above example are absolutely valid as well.
It is therefore recommended to use the name element to convey human-readable meanings.
7. Usage of name, description and uID
CPACS is designed to serve as a central data exchange format in fully automated process chains.
A key requirement is therefore that tools can automatically read and process an incoming CPACS file.
A second requirement is that users can interpret the data set.
To address both requirements, the following usage of the <name> and <description> elements in combination with the uID attribute is proposed:
name: A specification of the <name> element is usually mandatory for sequences of elements (e.g., if max occurrence is unbounded [1..*]).
Typical examples are wings/wing, aeroPerformance/aeroMap or missions/mission.
Such elements must be able to be listed by tools, especially for visualization and reporting purposes, where the <name> element serves as a concise and human-readable indicator of the actual meaning of the corresponding element in the list
(e.g., which wing, which aeroMap, which mission). This is usually a single word or a small number of words.
description:
The <description> element is usually optional and is used to add comprehensive and human-readable explanations.
This is usually at least one explanatory sentence.
uID: As described in more detail in Section 6, the uID attribute is mainly used for internal referencing of CPACS elements.
Further processing software, e.g. TiXI and TiGL, also use the uIDs to improve the robustness of the data query.
Consequently, the uID attribute serves as a machine-readable indicator and does not claim to be interpretable by human users.
In some practical use cases, the same string is chosen for uID and <name>.
However, restrictions on the choice of characters for the uID attribute must be considered, for example that no spaces may be used and the uID must be unique.
Main wing
This is the main wing which was designed by my awesome wing sizing design tool. Your tool should not try to read and interpret what I'm writing here as typos are not recognized by XML processors.
]]>
8. Symmetry
8.1. Specification of symmetric elements
Sometimes it might be useful to specify a part of the aircraft as symmetric instead of holding all the data twice in nearly identical form in the dataset (e.g. left and right wing are usually identical, except for the sign of the y-coordinate).
Hence, some parts offer the option to set a symmetry attribute:
]]>
There are six possible attribute values:
x-y-plane: Symmetry w.r.t. the x-y plane of the CPACS coordinate system
x-z-plane: Symmetry w.r.t. the x-z plane of the CPACS coordinate system
y-z-plane: Symmetry w.r.t. the y-z plane of the CPACS coordinate system
inherit: Symmetry inherited from parent element (default behavior, i.e. also applies if attribute not set)
none: Symmetry inheritance from parent element disabled
Note: It must be taken from the documentation of the respective element which of these attribute values may be set.
One example of how to apply the symmetry attribute is shown in Sec. 3.2.
Another simplified example shown below illustrates the combination of different symmetry properties of 4 wings:
Wing 1 is mirrored on the x-z plane.
Wing 2 has wing 1 as parent element, but suppresses its symmetry inheritance.
Wing 3 has wing 2 as parent element and sets a new symmetry at the x-y plane.
Wing 4 has wing 3 as parent element and no symmetry attribute specified. Thus, it inherits the symmetry at the x-y plane from wing 3.
Note: The corresponding transformations are not shown here.
8.2. Referencing symmetric elements
All nodes (e.g., <parentUID>) in CPACS that refer to a component holding the symmetry attribute (e.g., <wing>) might also have a symmetry attribute to specify how symmetry is propagated through the resulting element hierarchy.
The symmetry attribute of a referencing element may take three values:
symm,
def,
full:
def: The element refers to the geometric component that has a symmetry attribute and refers only to the defined side of the geometric component.
symm: The element refers to the geometric component that has a symmetry attribute and refers only to the symmetric side of the geometric component. (Similar to the previous _symm solution)
full: The element refers to the geometric component that has a symmetry attribute and refers to the complete component. (This is the default behaviour)
For example, to refer to the "other" side of a mirrored wing the following the following syntax might be used:
wing
]]>
Note: This feature is not implemented in TiGL. The upper figure is manually processed to illustrate the principle. In addition, there is an ongoing debate whether the approach is suitable for CPACS due to rapidly increasing complexity and unresolved implicit assumptions as to whether it is one or two components after mirroring. Therefore, it is advised to avoid using the symmetry attribute if possible.
9. Vectors and arrays
For large data sets (e.g. increments of aerodynamic coefficients due to control surface deflections) it is advantageous to map them via vectors and arrays instead of using a sequence of nodes for each data value.
Therefore vectors and arrays are defined as semicolon-separated lists in CPACS.
Via the documentation (derived from the XSD) of the corresponding nodes it has to be checked whether it is a vector or an array.
Vector
The vector is meant as a one-dimensional-array. In such a node, the values are given in a semicolon separated list:
0.;1.5;3.;4.5;6;7.5;9.
]]>
Array
As for vectors, multi-dimensional arrays provide values in a semicolon separated list. An array is always preceded by a sequence of vectors, containing the dimensions and index values. Which vectors of an array are dimensioning is specified in the respective documentation of the array.
1000.;2000.;3000.
InnerWingFlap
-1;-0.5;0;1
11.;12.;13.;14.;21.;22.;23.;24.;31.;32.;33.;34.
]]>
Values for cl increments:
Control parameter = -1
Control parameter = -0.5
Control parameter = 0
Control parameter = 1
Altitude = 1000m
11.
12.
13.
14.
Altitude = 2000m
21.
22.
23.
24.
Altitude = 3000m
31.
32.
33.
34.
10. Control Parameters
Control parameters are abstract parameters, linking a generic value (i.e., the control parameter) to a configurational state of a control device
(e.g., control surface, landing gear, engine settings, ...).
The basic idea is that this control parameter can be used in different CPACS nodes (e.g., aeroMaps), while the relationship between the abstract control parameter and the configurative state of a controllable component is defined in the latter.
Controllable compents can have multiple control functions (referred to as control devices), e.g., extraction and rotation state as well as the braking state of a landing gear.
Control parameters are predominantly used for control surfaces, which is why they are discussed in more detail below as an example.
However, the approach also applies to other components, such as landing gears.
In future the engines and other components will also be controlable via control parameters.
For control surfaces, the translation from the abstract control parameter to its physical state (i.e., deflection = rotation + translation)
is defined in a so-called <path>, which is componsed of a list of <step> elements.
The control parameter values for each step are arbitrary floating point values.
However, it is strongly recommended to use values between -1 and +1, or between 0 and +1 (depending on the type of control surface).
The smallest and the largest value implicitly define the maximum deflection limits.
It is mandatory, that the value “0” is within the specified range, as this value is treated as undeflected and used to specify a “clean” aircraft configuration (e.g. used in the clean aero performance map).
Furthermore, it it is mandatory for the <step> elements to be sorted in ascending order of the control parameters.
It is recommended, but not mandatory to specify a <step> with a <controlParameter> of 0.
Consequently, no <controlParameter> must be used twice within a single <path> definition.
Deflection values between two specified steps are handled by linear interpolation.
The following example shows the usage of control parameters within a control surface deflection path definition:
...
...
-1
-20.
-0.5
-10.
0
0.
1
5.
...
]]>
There is a possibility that more than one deflection command is applied to a control surface at the same time (e.g. coming from a <configurationDefinition> and from an explicit deflection).
Furthermore, a control surface could be deflected by one (or even multiple) control distributor and control device command(s) in parallel. In all these cases, the deflection commands have to be superposed in the following way:
The commands for each control distributor have to be added up to get a summed-up control distributor command input.
The command inputs for each control distributor have to be evaluated to come to a set of control device control parameters.
The control device control parameters for each control device (coming from control distributor and from control device commands) have to be added up.
The final control device control parameters for each control device have to be evaluated considering the corresponding <path> specification to come to the desired movements/deflections.
If command inputs or control parameters in step 2.) or 4.) are found to exceed the or boundaries of the defined range, an error should be returned from the evaluation.
11. Atmosphere
At some places in CPACS, an atmosphere has to be selected (e.g. for connecting an altitude with a certain pressure or density).
Currently, CPACS does only support a single atmospheric model: The ICAO Standard Atmosphere (ISA) from 1993 (see ICAO Doc 7488/3 'MANUAL OF THE ICAO STANDARD ATMOSPHERE', third edition, 1993).
It covers temperature, pressure, density, speed of sound, dynamic viscosity and kinematic viscosity with respect to altitude.
In CPACS, <altitude> means what is called 'geopotential altitude' (H) in the ISA reference document and is given in [m].
For details, see ISA manual, section 2.3, page E-viii f.
ISA covers a range from -5000 m to 80000 m.
Temperature offsets are introduced on top of the definitions in the ISA manual (which does not cover such variations).
The offset model is based upon the idea that the pressure at a fixed geopotential altitude is independent from temperature offset (pressure altitude).
The temperature offset changes only the density (following rho = p / Gas Constant / T) (and viscosity, of course)
CPACS 3.5
Release in November 2023
new headerType and versioning strategy
cpacsVersion marked as deprecated and moved to versionInfo node
fix typos:
various fixes in documentation
airportCompatibility
mAdditionalCenterTanks
consistency in globalBeamPropertiesType
capType: add uID
massBreakdown
genericMassTyp: add componentUID to link the corresponding components
mOperatorItemsType:
add mAdditionalCenterTanks
add mEngineAPUOils
add mRemovableCrewRests
add mToiletFluids
add mUnusableFuels
add mWaterReservoirs
add mMiscellaneous
align mLandingGear elements with more the new generic landingGears definition
add mGenericFuelTanks to mFuselageStructure
sparPositionType: add sparPositionCurve (defines a spar position via a point on a curve)
isLink attribute: marked as deprecated
Systems definition
aeroMaps, loadCases
configurationUID, ... --> configurationDefinitionUID
aircraftAnalysesType
add systemAnalyses
aircraftModelType
add configurationDefinitions
add systemArchitectures
engineType
add rotors
fuels replaced by chemicalEnergyCarriers and electricalEnergyCarriers
make sub-elements optional
genericSystemType: add components
operationalCaseType
add configurations
mPayload optional
vehiclesType
add systemElements
add rotorElements
add energyCarriers
weightAndBalanceCaseType
add configurations
aircraftModelType
add systemAnalyses/powerBreakdowns
add cryogenic fuel storage
add ducts definition
hinge line definition aligned with TiGL
fix wront type assignment in costHydraulicSystemsType
wingWingAttachmentType:
upperShellAttachment and lowerShellAttachment restricted to
upperShell and lowerShell
add wingCutouts
add fuselageStructuralMountsType
controlSurfaceTrackTypeType: joint position names in figures changed to count from P1
add CI schema validation
add python script for automatic syntax formatting
add automatic generation and publication of html documentation via GitHub actions and Appveyor
CPACS 3.4
Release in April 2022
Revision of decks definition (compatibility break)
Mass breakdown: add mSparSkins and mSparCells to mSpar
Mass breakdown: fix hierarchical error in mMiscellaneous (compatibility break)
Mass breakdown: fix typo in mPylon (compatibility break)
Nacelle guide curves: set description optional
Mission definition: add uID to elements in geographicPointConstraintType
Mission definition: add powerFraction,
powerRemaining and powerConsumed to missionSegmentEndConditionType
Mission definition: rename referenceEndCondition to referenceEndConditionUID in constraintSettingsType (compatibility break)
Mission definition: rename reqClassification to requirementClassification in flightPerformanceRequirementType (compatibility break)
Add contour coordinates for cell definition
Add vehicle independent node for external geometry
Remove paxFlow element from aircraftAnalysesType (compatibility break)
Docs: improve documentation of name, description and uID usage
Docs: add description of parentUID concept
Docs: add description of symmetry inheritance
Docs: add description of engine nacelles
Docs: add description of mission definition
General improvements of the documentation
CPACS 3.3
Release in June 2021
Revision of the mission definition including parameter lapses within segments (compatibility break)
Revision of the point performance definition (compatibility break)
Revision of performance requirements (compatibility break)
Revision of landing gears (compatibility break)
Revision of control surface tracks definition (compatibility break)
Load analysis: Revision of flightLoadCasesType (compatibility break)
Load analysis: Revision of aeroCasesType (compatibility break)
Load analysis: loadEnvelopesType relocated and envelope simplified to a single uID-Sequence (compatibility break)
Load analysis: Replaced dynamicAircraftModel elements by loadApplicationPointSets (compatibility break)
Flight dynamics: Group flightPerformance, flyingQualities and trim under flightDynamics parent node (compatibility break)
Introduced a configuration node to describe aircraft and payload configurations
Fuselage profiles: Introduced rectangle and super ellipse as standard profiles
Fuselage profiles: Added vector to specify curve parameters for profiles with kinks
Internal structure: Added standard profiles to profile based structural elements
Internal structure: Added ribPosts element to wingRibCrossSectionType
Internal structure: Upper and lowerCap now optional in sparCellType
Internal structure: Stringers and frames can reference sections
MassBreakdown: Set mass inertia Jxy, Jxz and Jyz optional
MassBreakdown: Added mMiscellaneous element
MassBreakdown: Added fuselage walls
Added flight envelope to aircraft global element
Added new base types: doubleVectorBaseType, posIntVectorBaseType, doubleArrayBaseType
Added 'none' and 'inherit' to list of symmetry flags
Set mapType attribute of vector and array elements to optional (requires TiXI>=3.1)
AeroMaps: Defined angleOfSideslip as input and added distinction between minimum and maximum angleOfAttack in aeroLimitMaps (compatibility break)
AeroMaps: Added missing singular incrementMap element to incrementMaps in aeroLimitsMap (compatibility break)
AeroMaps: Adopted the camelCase style for damping derivatives (compatibility break)
Introduced common nomenclature for speeds and altitudes (compatibility break)
Control distributors are set to optional
Added instructions for superposition of control surface deflections
Further elaboration of development standards
General improvements of the documentation
CPACS 3.2
Release in February 2020
Replaced tool-specific elements with xsd:any element and strict schema request for validation
UIDs adapted to type xsd:ID and xsd:IDREF
UIDs optional for transformationType and pointTypes
Replaced xsd:sequence elements with xsd:all elements where possible
CpacsVersion element set to optional
GuideCurves are now optional for nacelleCowlType
Documentation adaptions
CPACS 3.1
Release in August 2019
Redefinition of aeroPerformanceMaps
Added nodes for detailed engine pylons and nacelles
Added nodes to model generic walls
Extension of material definition
Added fuselage compartment definition
Added fuselage fuel tank definition
Explicit wing stringer definition integrated into wing stringer definition
RelativeDeflections renamed to control parameters
Control distributors modified to only have a single command input vector
"cpacsVersion" restricted to current schema version
Code cleanup
Cpacs_schema.xml removed
Documentation adaptions
CPACS 3.0
Release in Jul 2018
New component segment definition; this is affecting all structural components of wings
Renamed angleOfYaw into angleOfSideslip
Fixes in documentation
Made all uID attributes required
Minor fixes in choices and typos
Added nodes for the geometry of generic system components
Added performance requirements for aircraft models
Redefined the whole mission definition including point performances
Made link to missionUID in trajectory optional
Added new parameters to enginePerformanceMap
Relocated mFixedLeadingEdge and mFixedTrailingEdge within the massBReakdown structure
Changed aeroPerformanceMap to use altitude and standard atmosphere instead of reynolds number
Added an optional local direction for guide curves and an illustration image
Announced toolspecifics definitions as deprecated; will be removed from CPACS in next release and should be managed in separate namespace by tool maintainers
Added an option for aerodynamic performance maps of elastic aircraft
Enabled the definition of multiple aeroPerformanceMaps
Enabled the use of spar points for rib placement and rib points for spar placement
Added explicit stringer definitions for wing cells
All issues for this release can be found online
https://github.com/DLR-LY/CPACS/issues
CPACS 2.3.1
Release in Jul 2016
CPACS 2.3.1 is a beta release, all parameters may be subject to change.
Added a branch for the definition of design studies.
Added thermal properties for materials.
Revised the definition of flights/flightplans.
Added an airline definition.
Added structure for skid gear components.
Changed the units for material density to SI units.
Revised the top level fleets node and put it into the new airline node.
All issues for this release can be found online
https://github.com/DLR-LY/CPACS/issues
CPACS 2.3
Release in Nov 2015
CPACS 2.3 is the fourth public release of CPACS. Major changes include:
Included vector notation for weight and balance.
Included flight system and flight dynamic information.
Included top level aircraft requirements.
Included a prototype for detailed nacelle geometries.
Included structural mounts.
Extended aero data set for loads.
Extended the mass breakdown.
Updated the symmetry definition, please take a look at the documentation point 5 and 6.
All issues for this release can be found online
https://github.com/DLR-LY/CPACS/issues
CPACS 2.2.1
Release in Feb 2015
CPACS 2.2.1 is a beta release, all parameters may be subject to change.
Included preliminary definition of guidecurves.
Included additional means to describe the wing structure.
Included preliminary fuselage fuel tanks.
Included preliminary load envelope.
Included preliminary flight performance and flight qualities. (flight dynamics will follow)
Updated toolspecifics
Updated uncertainty definition
all issues can be found online
http://code.google.com/p/cpacs/issues/list
CPACS 2.2
Release in May 2014
CPACS 2.2 is the third public release of CPACS. Major changes include
Additions and changes to the loadCaseType.
Included additional genericGeometricEntities for bellyfairings etc.
The mass breakdown is extended for a more detailed fuselage structure.
Steadiness information on the geometry is excluded from CPACS 2.2. CPACS 2.3 will include optional guidelines for smoother surfaces.
Uncertainties can now be specified (CPACS 2.2alpha doubleBaseType, CPACS 2.2 also in vector notations)
all issues can be found online
http://code.google.com/p/cpacs/issues/list
CPACS 2.1
Release in May 2013
CPACS 2.1 is the second public release of CPACS. Most of the implementation was already included in CPACS 2.01
included fuselage structure and cabin definition
all data is defined according to the CPACS coordinate system. That is the initial coordinate system in which geometries are defined. Therefore, it can but must not meet your body axis.
the mass breakdown is extended for a more detailed wing structure
profiles can now be included based on a two-dimensional class shape transformation. The old parametrization will still be available. TIGL will learn CST asap.
all issues can be found online
http://code.google.com/p/cpacs/issues/list
CPACS 2.01
Release in Nov 2012
CPACS 2.01 is an internal release for the VAMP project. It is the testbed for CPACS 2.1
included fuselage structure
additions to the load case definition
all issues can be found online
http://code.google.com/p/cpacs/issues/list
CPACS 2.0
Release in Mar 2012
CPACS 2.0 is the first public release
large impacts on the documentation
all issues can be found online
http://code.google.com/p/cpacs/issues/list
compatible with TIGL 2.0
excluded fuselage structure, reintegration in CPACS 2.1
CPACS 1.6
Release in Jul 2011
Thanks for the input on the documentation to Felix Dorbath, Till Pfeiffer, Alexander Koch, Falk Heinecke and Tom Otten
preliminary added enginePylons
deleted seatAssemblyPositionType
updated toolspecific blocks from handbook aero and cpacs mass updater
added weight and balance definition
added loads reference axis and dynamic aircraft model
added wing documentation
added weights documentation
added fleet documentation
added paramam toolspecific documentation
added wing tank definition
changed some names in the massBreakdown
deleted old loadCaseDefinitions
no more plural element for loadAnalyses
shifted groundforces to groundloadcases, this will need an update
added noseLandingGear
mainLandingGear can now have plural SideStruts
CPACS 1.5
Release in Feb 2011
uID for transformation
extended stringUIDBaseType with optional attribute isLink
all elements xxxUID are now of Type stringUIDBaseType
added new material definition from FA to distinguish between different material types
changed fuselage structure definition due to input from BK
changed rib definition in cells in component segments
cleaned up material definition in component segments
added cpacsVersion information to the header and updates types
added area and length to the loadCase reference on wing strips
added wingFuselageAttachment
CPACS 1.4
Release in Nov 2010
Geometry definition for engine and nacelle added
Trailing Edge Devices, Leading Edge Devices and Spoilers added
Rotorcraft added, similar to aircraft
Splitted up multiple Point Types
sparCell added uID
new inline Documentation introduced in CPACS type
CPACS 1.3
Release in Aug 2010
Fuel definition added
Introduced component segments for the wing structure
Mission definition was updated
VSAero toolspecific data updated
CPACS 1.2
Release in May 2010
Fuselage Structure Elements are updated following the input from BK
stringers>arbitrary additional parameters: yBezugAtStartX, zBezugAtStartX, yBezugAtEndX, zBezugAtEndX
paxCrossBeams additional parameters: startX, endX
cargoCrossBeams additional parameters: startX, endX
paxCrossBeamStruts additional parameters: startX, endX
cargoCrossBeamStruts additional parameters: startX, endX
structure>pressureBulkhead: positionX instead of positionZ
reinforcementNumberVertical: number of vertical reinforcements
reinforcementNumberHorizontal: number of horizontal reinforcements
maxFlectionDepth: max camber of pressure bulkhead
reinforcementNumber: number of reinforcements rear pressure bulkhead
sheetProperties: definition of sheet properties
innerRadius: inner radius of the pressure bulkhead
Dummy Wingbox element is included. This definition needs further enhancements
cpacs>vehicles>aircraft>model>fuselage>fuselage>structure
Wingbox:
xStart: start of the wingbox area
xEnd: end of the wingbox area
zStart: upper limit of the wingbox area
Damping Derivatives are added in the form of dcfxdp, dcfxdq, dcfxdr, dcfydp, etc. The data will be stored in the model/global/aeroperformaneMap under a new dampingDerivatives element. Unit is deg/sec.
StructureProfiles are defined in the profiles element. They are referenced in structuralElements for several entities such as stringer, frame etc. Currently they are referenced via 'structuralProfileUID' for name consistency it should be either only 'structure' or only 'structural'
Control Commands. The chain between pilot inputs and controlsurface deflections is now closed.
Parameters located at cpacs\vehicles\aircraft\model\systems
cockpitControl: links from pilotInput to commandCase
commandCase: links from commandCase to controlDistributor or controlFunction
controlDistributor links to the controlSurface
controlLaws includes controlModes automatic and manual
controlModes contain controlFunctions
TraFuMo toolspecific data added
CPACS 1.1
Release in Feb 2010
Fleets model added. The fleets modeling from CATS is introduced to CPACS 1.1
Reference changed. The reference type in wingSegmentStripCoefficientsType was changed from referenceType to pointType
Actuator attachment
Relative spanwise position of the actuator.
Eta refers to the dimensions of the control surface.
Definition of the position and material properties of
the control surface actuator attachment.
Definition of the position and material properties of
the control surface actuator attachment.
Please refer to the picture below for the definition
of the parameters:
Definition of the relative chordwise position
of the parent actuator attachment. Xsi refers to the parents
dimensions.
Definition of the relative height position of
the parent actuator attachment. relHeight refers to the parents
dimensions.
Definition of the material properties of the
actuator attachment at the parent.
actuatorFuselageWingAttachmentType
actuatorFuselageWingType
Reference to the actuator.
Definition of the actuator to fuselage
attachment.
Definition of the actuator to wing attachment.
Definition of the position and material properties of
the parent actuator attachment.
Definition of the position and material properties of
the parent actuator attachment.
Please refer to the picture below for the definition
of the parameters:
Definition of the relative chordwise position
of the parent actuator attachment. Xsi refers to the parents
dimensions.
Definition of the relative height position of
the parent actuator attachment. relHeight refers to the parents
dimensions.
Definition of the material properties of the
actuator attachment at the parent.
actuatorsFuselageWingType
Definition of one actuator (e.g. trim actuator
of an HTP) of the attachment.
Aerodynamic loads
Description of the aerodynamic loads
Angle of attack [deg]
Angle of sideslip [deg]
Aerodynamic coefficients
A set of aerodynamic coefficients in the aerodynamic coordinate system
Drag coefficient in aerodynamic
coordinates
Coefficient of the side force vector in
aerodynamic coordinates (perpendicular
to lift and drag)
Lift coefficient in aerodynamic
coordinates
Aerodynamic moment around d-axis of the aerodynamic coordinate system
Aerodynamic moment around s-axis of the aerodynamic coordinate system
Aerodynamic moment around l-axis of the aerodynamic coordinate system
Specification
Specification of the vehicle properties and dynamics
Altitude
Mach number
Angle of sideslip [deg]
Angle of attack [deg]
Target lift coefficient
Normalized roll rate [rad/sec]. It is specified around the global x-axis
with the aircraft model's global reference point as origin and
nondimensionalized by: pStar = p * reference length / flow speed.
Normalized pitch rate [rad/sec]. It is specified around the global y-axis
with the aircraft model's global reference point as origin and
nondimensionalized by: qStar = q * reference length / flow speed.
Normalized yaw rate [rad/sec]. It is specified around the global z-axis
with the aircraft model's global reference point as origin and
nondimensionalized by: rStar = r * reference length / flow speed.
Reference to a weight and balance description
Aerodynamic load cases
Combines a set of aerodynamic load cases
Aerodynamic load case
Specification of an aerodynamic load case
Name
Description
Aerodynamic loads of components
Specification of the aerodynamic loads of components
Aerodynamic data of components
Aerodynamic data of individual components of the aircraft (e.g. control surface loads and hinge moments)
Reference to a component uID
Aerodynamic loads of the vehicle
Description of the aerodynamic loads of the vehicle
aeroelasticDivergenceType
AeroelasticDivergence type, containing the results from
aeroelastic analysis
aeroelasticStaticMaxDisplacementType
AeroelasticStaticMaxDisplacement type, containing the
Maximum static displacement from aeroelastic analysis
Maximum translation
Maximum rotation
Aeroelasticity
Aeroelastics type, containing the results from
aeroelastic analysis
Increment maps for limitation values due to movable device deflections
Specification of aerodynamic coefficient increments due to movable device deflections (e.g., control
surfaces or landing gears).
Increment maps for limitation values due to movable device deflections
Specification of aerodynamic coefficient increments due to movable device deflections (e.g., control
surfaces or landing gears).
Configuration uID
Reference to an increment map of the aeroPerformanceMap
Increments of the vehicle operation limits
Aerodynamic limitations
This map explicitly specifies limitations of a vehicle in terms of angles of attack and sideslip angles.
All vectors, i.e. altitude, machNumber, angleOfSideslip and angleOfAttack,
must have the same length. To avoid redundancy with the aeroPerformanceMap, this type does not contain any aerodynamic coefficients.
Since angleOfSideslip and angleOfAttack are closely interdependent for a given machNumber and altitude combination,
a positive and negative maximum angleOfAttack is defined for a given combination of machNumber, altitude and angleOfSideslip.
The limits of angleOfSideslip can be determined by evaluating the nominal decrease of angleOfAttack values
or by agreeint with the data supplier that the minimum and maximum value of the angleOfSideslip vector corresponds with physical limits.
In order to avoid data redundancy, the operational limits should not reflect the extrema of aerodynamic coefficients as these can be extracted from the performanceMap via interpolation.
Note: In future CPACS versions, a revision of the aeroLimitsMap will be targeted, since operational limits are not a purely aerodynamic issue.
Altitude [m]
Mach number
Angle of sideslip
Vehicle operation limit
Vehicle operation limit defined by sets of minimum and maximum
angleOfSideslip
and minimum and maximum
angleOfAttack
for a given altitude and Mach number.
This might be, e.g., a safety margin to the angle of attack at maximum lift or the flight
attitude a fighter aircraft is capable to fly in stalled conditions. The corresponding aerodynamic coefficients must
be extracted from the aeroPerformanceMap.
Minimum angle of attack defining the operation limit. Must be a vector of the same length as angleOfSideslip, machNumber and altitude. [deg]
Maximum angle of attack defining the operation limit. Must be a vector of the same length as angleOfSideslip, machNumber and altitude. [deg]
Aerodynamic map
The aeroMap contains aerodynamic coefficients and derivatives for a specific set of aerodynamic
and configurative boundary conditions.
The
aeroMap
allows for the simultaneous specification of multiple
controlDevice
settings.
In this case, it is assumed that a cumulative setting is built by summing up the individual settings. The correct
sequence of this summation is described in the
controlDistributorType
documentation.
Name
Description
Boundary conditions
Specification of boundary conditions.
Offset from temperature of the
atmospheric model [K]. For more details
on atmospheric models, please refer to
documentation of the <CPACS> root
element.
Configuration settings
Increment maps for aerodynamic coefficients
Increment map from aerodynamic coefficients
The increment map is composed of two-dimensional arrays. The first dimension is given by the
length of the input vectors of the baseline aeroPerformanceMap and the second dimension by the vector of relative
deflections (or command inputs) of control surfaces (or control distributors). An example is described in the <CPACS>
root element.
Reference to the uID of a control device, e.g. a control surface or a landing gear
Value of the command parameters of a control distributor. If not given explicitly in the control distributor, linear interpolation between the neighboring points is required.
Reference to a control distributor uID
Command inputs of a control distributor given as vector. If not given explicitly in the control distributor, linear interpolation between the neighboring points is required.
Increment of drag coefficient in aerodynamic coordinates
Increment of coefficient of the side force vector in aerodynamic coordinates (perpendicular to lift and drag)
Increment of lift coefficient in aerodynamic coordinates
Increment of cmd
Increment of cms
Increment of cml
aeroPerformanceMapRCType
AeroPerformanceMapRC type, containing a performance map
with aerodynamic data. Array order is: angleOfAttack min->max
then angleOfSideslip then altitude then machNumber
Atmospheric model and temperature offset
Mach number
Altitude
Sideslip angle
Angle of attack
Name and version of the tool used to compute
the aerodynamic performance
Modeling level of the methods used to compute
the aerodynamic performance. The higher the analysisLevel, the
higher the quality of the results. Possible use of
analysisLevel: 0- 9 = Statistical models, 10-19 = Analytic
models, 20-29 = Lifting line method, 30-39 = Panel method, 40-49
= Panel-BL-coupled method, 50-59 = Full potential method, 60-69
= Full potential-BL coupled method, 70-79 = CFD euler method,
80-89 = CFD euler-bl coupled method, 99-99 = CFD RANS method,
>=100 = Experimental data.
aeroPerformanceMapsRCType
aeroPerformanceMapsRC type, containing multiple
aeroPerformanceMapRC nodes for different cases
Aerodynamic coefficients and derivatives
Description
The aeroPerformanceMap contains a map with aerodynamic data of the complete aircraft in the form of nondimensional coefficients.
The force coefficients in i-direction (ci) are nondimensionalized by dynamic pressure and reference area,
the moment coefficients (cmi) by dynamic pressure, reference area and reference length.
All coefficients in the aeroPerformanceMap relate to
the aerodynamic coordinate system which is deducted from the CPACS coordinate system by
the transformations of angle of attack and angle of yaw. See the documentation of the
CPACS element for further details.
The dependent parameters of the aeroPerformanceMap are
altitude,
machNumber,
angleOfSideslip and
angleOfAttack.
These elements are vectors of equal length, where values with identical indices belong together. The solution vectors ci and cmi have the same length as the input vectors. Shown below is an example where with 10 values per vector:
<altitude mapType="vector">12e+02;12e+02;12e+02;12e+02;12e+02;12e+02;12e+02;12e+02;12e+02;12e+02</altitude>
<machNumber mapType="vector">0.2;0.2;0.2;0.2;0.2;0.2;0.2;0.2;0.2;0.2</machNumber>
<angleOfSideslip mapType="vector">0;0;0;0;0;2;2;2;2;2</angleOfSideslip>
<angleOfAttack mapType="vector">-2;0;2;4;6;-2;0;2;4;6</angleOfAttack>
<cd mapType="vector">0.056;0.094;0.132;0.17;0.208;0.072;0.11;0.148;0.186;0.224</cd>
<cs mapType="vector">0.;0.;0.;0.;0.;0.01;0.015;0.02;0.025;0.03</cs>
<cl mapType="vector">-0.1;0.04;0.18;0.32;0.46;-0.08;0.03;0.14;0.25;0.36</cl>
The aerodynamic coefficients for
altitude=1200m,
machNumber=0.2,
angleOfSideslip=0° and
angleOfAttack=6° can be found at the 5th index:
cd=0.208, cs=0 and cl=0.46.
Altitude [m]
Mach number
Sideslip angle [deg]
Angle of attack [deg]
Drag coefficient in aerodynamic coordinates
Coefficient of the side force vector in aerodynamic coordinates (perpendicular to lift and drag)
Lift coefficient in aerodynamic coordinates
aeroPerformanceType
aeroPerformance type, containing performance maps with
aerodynamic data of an airfoil.
Aerodynamic performance map of the full
configuration
Aerodynamic performance maps of isolated
fuselages
Aerodynamic performance maps of isolated wings
Aerodynamic performance maps of control
surfaces
Aerodynamic performance maps of isolated
airfoils
Aerodynamic performance
The aerodynamic coefficients and derivatives are stored in aerodynamic maps. Individual maps can be used to
gather the aerodynamic characteristics for specific boundary conditions.
Global analysis information
Results from several analysis
modules connected to CPACS
AircraftAnalyses type, containing detailed analysis
data of the aircraft
Within this element results from analysis modules are
stored that rely to the overall definition of the aircraft. These
include e.g. aerodynamic data or loadCases
For further documentation please refer to the
respective elements.
Control elements
Specification of control element settings. Control elements can be controlDistributors
or individual control devices, such as control surfaces or landing gears.
Control element
Specification of an control element setting. A control element can be a controlDistributor
or an individual control device, such as a control surface or a landing gear.
Reference to the uID of a control device, e.g. a control surface or a landing gear
Control parameter of the control device
Reference to a control distributor uID
Value of the command parameter of a control distributor. If not given explicitly in the control distributor, linear interpolation between the neighboring points is required.
Global data
AircraftGlobal type, containing global data of the
aircraft
designRange equals the full payload max
range, i.e. point B in payload range
diagram
Aircraft model
The aircraftModelType contains the geometric aircraft model and associated data.
Elements specifying the geometry of the aircraft are fuselages, wings, engines (referenced via uID),
enginePylons, landingGear, systems (to some extend) and genericGeometryComponents.
Other elements are dedicated to additional data associated to this aircraft model.
Brief and concise analysis results are stored in the global node.
The analysis node contains extensive results from multidisciplinary analysis modules.
In the current CPACS version requirements only refer to the aircraft performance and are therefore specified in the performanceRequirements node.
Name of the aircraft model
Description of the aircraft model
Aircraft
The aircraftType contains a list of aircraft models.
Note: Since there is no distinction between plural and singular in English, aircraft refers to plural form, while a single aircraft itself is referenced as model.
airfoilAeroPerformanceType
airfoilAeroPerformance type, containing performance maps
with aerodynamic data of an airfoil.
Reference to the uID of the analysed airfoil
References used for the calculation of the
force and moment coefficients of the airfoil (in the airfoil
axis system!)
Calculated aerodynamic performance maps of the
airfoil
airfoilsAeroPerformanceType
airfoilsAeroPerformance type, containing
airfoilsAeroPerformance
airframeMaintenanceCostType
Airlines
Contains a list of different airlines
airlineType
Describes a specific airline and their fleet
Name of the airline
Description of the airline
Airport compatibility
Airports
Airports type, containing data of the airports
airportType
Airport type, containing data of an airport
Name of airport
Description of airport
IATA 3-letter-code
ICAO 4-letter-code
Position in degrees north
Position in degrees east
Airport elevation
alignmentCrossBeamType
Offset in direction of extrusion, first side
(absolute value)
Offset in direction of extrusion, second side
(absolute value)
Rotation around local x axis (extrusion axis)
Translation along local y axis (perpendicular
to extrusion axis)
Translation along local z axis (perpendicular
to x ynd y axes)
alignmentFloorPanelType
Offset from seat rail 1 reference Position in
local y direction (in plane of panel, absolute value)
Offset from seat rail 2 reference position in
local y direction (in plane of panel, absolute value)
Offset from seat rail 1 reference position in
local z direction (in plane of panel, absolute value))
alignmentStringFrameType
Rotation around local x axis (extrusion axis)
Translation along local y axis (perpendicular
to extrusion axis)
Translation along local z axis (perpendicular
to x ynd y axes)
alignmentStructMemberType
Offset in direction of extrusion (absolute
value)
Rotation around local x axis (extrusion axis)
Translation along local y axis (perpendicular
to extrusion axis)
Translation along local z axis (perpendicular
to x ynd y axes)
Alternating current
Effective voltage (also peak voltage) [V]
Frequency [Hz]
Frequency [Rad]
Alternating current
Effective voltage (also peak voltage) [V]
Frequency [Hz]
Frequency [Rad]
Anisotropic material properties for 2D materials
Defines the material properties for a linear anisotropic material in the plane stress state (i.e., shell). The stress-strain relationship is defined as:
The terminology of this complex type refers to the following literature:
[1] R. M. Jones, Mechanics Of Composite Materials, 2 New edition. Philadelphia, PA: Taylor and Francis Inc, 1998.
[2] J. N. Reddy, Mechanics of Laminated Composite Plates and Shells: Theory and Analysis, Second Edition. CRC Press, 2004.
Coefficient 11 of reduced stiffness matrix [N/m^2]
Coefficient 12 of reduced stiffness matrix [N/m^2]
Coefficient 13 of reduced stiffness matrix [N/m^2]
Coefficient 22 of reduced stiffness matrix [N/m^2]
Coefficient 23 of reduced stiffness matrix [N/m^2]
Coefficient 33 of reduced stiffness matrix [N/m^2]
Thermal expansion coefficient in material direction
1 [1/K]
Thermal expansion coefficient in material direction
2 [1/K]
Thermal expansion coefficient in material direction
12 [1/K]
Thermal conductivity of the material in material direction 1 [W/(m*K)]
Thermal conductivity of the material in material direction 2 [W/(m*K)]
Thermal conductivity of the material in material direction 3 [W/(m*K)]
Allowable stress for tension in material direction 1 [N/m^2]
Allowable stress for compression in material direction 1 [N/m^2]
Allowable stress for tension in material direction 2 [N/m^2]
Allowable stress for compression in material direction 2 [N/m^2]
Allowable stress for shear [N/m^2]
Allowable strain for tension in material direction 1
Allowable strain for compression in material direction 1
Allowable strain for tension in material direction 2
Allowable strain for compression in material direction 2
Allowable strain for shear
Anisotropic material properties for 3D materials
Defines the material properties for a linear anisotropic material in three spatial directions (i.e., solid). The stress-strain relationship is defined as:
The terminology of this complex type refers to the following literature:
[1] R. M. Jones, Mechanics Of Composite Materials, 2 New edition. Philadelphia, PA: Taylor and Francis Inc, 1998.
[2] J. N. Reddy, Mechanics of Laminated Composite Plates and Shells: Theory and Analysis, Second Edition. CRC Press, 2004.
Coefficient 11 of stiffness matrix [N/m^2]
Coefficient 12 of stiffness matrix [N/m^2]
Coefficient 13 of stiffness matrix [N/m^2]
Coefficient 14 of stiffness matrix [N/m^2]
Coefficient 15 of stiffness matrix [N/m^2]
Coefficient 16 of stiffness matrix [N/m^2]
Coefficient 22 of stiffness matrix [N/m^2]
Coefficient 23 of stiffness matrix [N/m^2]
Coefficient 24 of stiffness matrix [N/m^2]
Coefficient 25 of stiffness matrix [N/m^2]
Coefficient 26 of stiffness matrix [N/m^2]
Coefficient 33 of stiffness matrix [N/m^2]
Coefficient 34 of stiffness matrix [N/m^2]
Coefficient 35 of stiffness matrix [N/m^2]
Coefficient 36 of stiffness matrix [N/m^2]2]
Coefficient 44 of stiffness matrix [N/m^2]]
Coefficient 45 of stiffness matrix [N/m^2]
Coefficient 46 of stiffness matrix [N/m^2]
Coefficient 55 of stiffness matrix [N/m^2]
Coefficient 56 of stiffness matrix [N/m^2]
Coefficient 66 of stiffness matrix [N/m^2]
Thermal expansion coefficient in material direction
1 [1/K]
Thermal expansion coefficient in material direction
2 [1/K]
Thermal expansion coefficient in material direction
3 [1/K]
Thermal expansion coefficient affecting strain in material direction
23 [1/K]
Thermal expansion coefficient affecting strain in material direction
31 [1/K]
Thermal expansion coefficient affecting strain in material direction
12 [1/K]
Thermal conductivity of the material in material direction 1 [W/(m*K)]
Thermal conductivity of the material in material direction 2 [W/(m*K)]
Thermal conductivity of the material in material direction 3 [W/(m*K)]
Thermal conductivity of the material which couples heat flux in material direction 2 with temperature gradient in material direction 3 [W/(m*K)]
Thermal conductivity of the material which couples heat flux in material direction 3 with temperature gradient in material direction 1 [W/(m*K)]
Thermal conductivity of the material which couples heat flux in material direction 1 with temperature gradient in material direction 2 [W/(m*K)]
Allowable stress for tension in material direction 1
[N/m^2]
Allowable stress for compression in material
direction 1 [N/m^2]
Allowable stress for tension in material direction 2
[N/m^2]
Allowable stress for compression in material
direction 2 [N/m^2]
Allowable stress for tension in material direction 3
[N/m^2]
Allowable stress for compression in material
direction 3 [N/m^2]
Allowable stress for shear in 2-3 plane [N/m^2]
Allowable stress for shear in 3-1 plane [N/m^2]
Allowable stress for shear in 1-2 plane [N/m^2]
Allowable strain for tension in material direction 1
Allowable strain for compression in material
direction 1
Allowable strain for tension in material direction 2
Allowable strain for compression in material
direction 2
Allowable strain for tension in material direction 3
Allowable strain for compression in material
direction 3
Allowable strain for shear in 2-3 plane
Allowable strain for shear in 3-1 plane
Allowable strain for shear in 1-2 plane
Category (ATA chapters)
Environmental control
Auto flight
Communications
Electrical power
Equipment/furnishings
Fire protection
Flight controls
Fuel
Hydraulic power
Ice and rain protection
Landing gear
Lights
Water/waste
Cabin system
Cargo and accessory compartment
atmosphericModelType
Defines the the athmospheric model which should be used.
Currently there is only a single option which is ISA for ICAO Standard
atmosphere (ISA) from 1993. For more details on atmospheric
models, please refer to documentation of the <CPACS> root
element.
Atmospheric model (e.g. ISA for ICAO Standard
atmosphere (ISA) from 1993).
Offset from temperature of the atmospheric model [K].
For more details on atmospheric models, please refer to documentation
of the <CPACS> root element.
Atmospheric model
Available options: ISA. See documentation of <CPACS> root element for further details.
Definition of attachment pins for the wing-fuselage
attachment.
Definition of attachment pins for the wing-fuselage
attachment.
Attachment pin of the wing-fuselage-attachment.
Attachment pin of the wing-fuselage-attachment.
Definition which translation degrees of
freedom are blocked. Default x=0 (free); y=1 (blocked); z=1
(blocked).
Bogie axle assemblies
A list of axles that are attached to the bogie
and their relative position to it
Bogie axle assembly
Description of an axle installed on the bogie and its
relative position to it
Relative position of the axle to the bogie (if more than one axle is defined; 0 = forward end of bogie; 1 = rear end of bogie)
Axle
Geometric description and material properties of the
landing gear axle
Length of the axle. For a single wheel, the length is equal to the distance between the center of the piston and the center of the wheel. For two wheels, the length is equal to the distance between the centers of the wheels with the axis being centered w.r.t. to the Piston.
Axle shaft properties
Number of wheels attached to this axle
Defines the side of the first wheel (inboard or outboard; inboard corresponds to the negative y-direction or in flight direction left) for odd number of wheels on this axis. Each additional wheel is the added on the opposite site of the previous wheel.
Properties of the wheel(s) attached to this axle. If more than one wheel is attached, all wheels on a single axis have the same properties.
Batteries
Battery
beamCrossSectionType
beamCrossSectionType, containing the beam geometrical
properties
beamStiffnessType
globalBeamStiffnessType, containing the beam
stiffnesses such as EA, EI
blockedDOFType
Bogie
Geometric description and material properties of the
landing gear axle bogie (including the axle configuration)
Length of the bogie
Tilt angle of the bogie in airborne conditions
booleanBaseType
Base type for boolean nodes (including external data
attributes)
Bounding Box
Length in x
Length in y
Length in z
Origin
A list of uIDs referencing other structural/geometric
elements that shall serve as a boundary of the wall
element. Possible references are floor, wall or
genericGeometryComponent. A major requirement is that
the referenced element has an intersection with the wall
for at least the distance between two wall positions. So
that a full geometric face of the wall is bounded by it.
Neighbouring wall faces that are not completely bounded
by the reference element are not affected.
UID referencing another
structural/geometric element that shall
serve as a boundary of the wall element.
Possible references are floor, wall or
genericGeometryComponent.
System breakdown data
Cabin aisles
Aisle
Aisles has as many entries as there are aisles in the
cabin. In a normal single aisle there are two aisles: the cabin
aisle and the aisle leading to the cockpit.
Name
Description
Longitudinal coordinates. The
number of coordinates can be chosen as appropriate, the minimum
number is two. The coordinates are relative to the cabin origin.
Center points of the aisle. The
y-vector has to have same length as the x-vector. The aisle
stretches equally left and right of the provided y-coordinate.
Width of the aisle at floor level at each
y-coordinate
Cabin geometry contours
Cabin geometry contour line collection type. By providing more than one entry,
a 3D cabin space can be described.
Cabin geometry contour
Type to define a lateral position value "y" at a given height "z" (in the parent deck coordinate system)
for each entry "x" in the parent cabin geometry definition.
Vector with y-coordinates
Height z
Geometry
[WARNING: This type is known to be susceptible to inconsistencies and might therefore be removed in a future version of CPACS]
The geometry of the cabin roughly corresponds to the available design space in the cabin.
It is given in terms of constant height contour lines.
The lines all share a common x-vector.
The y vector provides the lateral contour at z-coordinate provided by the constant value z.
One or more contour lines can be given.
The cabin geometry is assumed to be symmetric.
Name
Description
Vector of x coordinates
Cabin spaces
Space
spaces describe areas in the cabin that need to be
clear for use as emergency area. Depending on the type of area,
it can have a height limit. The spaces are required for
downstream cabin design, for example to describe an empty cabin.
Name
Description
Vector with x-coordinates. These describe an area, so they
are not monotonous ascending.
Vector with y-coordinates at given x-coordinates. Warning:
x-y do not represent a function as single x-positions can have
multiple y-coordinates. Hence, no interpolation is possible.
Height above the floor that is required to
be empty of any objects
Cap
SparCap type, containing the cross section area of the
spar cap and the material properties.
Please find below a picture where all spar cross
section parameters as well as the orientation references for
the material definition can be found:
Area of the cap
Cargo container elements
Cargo container element collection type
Cargo container element for use in the decks
Name
Description
Cargo container geometry
Contour: single or double
Delta x
Delta y
Delta y of the base
Delta z
Delta z kink
Cargo containers
Cargo container instance collection type.
Cargo container
Cargo container type for placing an instance of a cargo container in the parent deck.
Name
Description
UID of the cargo container element in the cpacs/vehicles/deckElements node
Position in x
Position in y
cargoCrossBeamsAssemblyType
CargoCrossBeamsAssembly type, containing cargo
crossBeam assemblies
cargoCrossBeamStrutsAssemblyType
CargoCrossBeamStrutsAssembly type, containing cargo
crossBeam strut assemblies
cargoDoorsAssemblyType
CargoDoorsAssembly type, containing cargo door
assemblies
Ceiling panel
Ceiling panel element collection type
Ceiling panel element for use in the decks
Ceiling panels
Ceiling panel instance collection type.
Ceiling panel
Chordwise positioning of wing cells.
CellPositioningChordwise defines the chordwise direction of a wing cell either in two xsi
(xsi1 at innerBorder and xsi2 at outerBorder) coordinates, via referencing a spar-uID or via a
contour coordinate in chordwise direction.
Relative chordwise position of the inner end.
Relative chordwise position of the outer end.
Reference to a spar as chordwise border.
Chordwise contour coordinate as chordwise border. 0 equals LE, 1 equals TE.
Spanwise positioning of wing cells.
CellPositioningSpanwise defines the chordwise direction of a wing cell either in two eta
(eta1 at leadingEdge and eta2 at trailingEdge) coordinates, via referencing a rib-uID or via a contour
coordinate in chordwise direction.
Relative spanwise position of the forward end.
Relative spanwise position of the rear end.
RibNumber is the reference to the rib number of the rib set which is referenced by 'ribDefinitionUID'.
Reference to a ribDefinition set. The single rib of this ribDefinition set is defined by using 'ribNumber'.
Spanwise contour coordinate as spanwise border. 0 equals root, 1 equals tip.
centerFuselageAreasAssemblyType
centerFuselageAreasAssembly type, containing center
fuselage area assembly
centerFuselageAssemblyType
CenterFuselageAssembly type, containing wing box
assemblies
Choice between different center fuselage
modelling options
Simplified center fuselage definition (rigid
body)
UID of first frame in rigid center fuselage
area
UID of last frame in rigid center fuselage
area
UID of start stringer to define center
fuselage area
UID of end stringer to define center fuselage
area
Detailed low wing center fuselage definition
(draft definition)
Detailed high wing center fuselage definition
(draft definition)
centerFuselageHighWingConfiguration
centerFuselageKeelbeamType
CenterFuselage / Keelbeam definition between mainframe1
und mainframe3
centerFuselageLateralPanelsType
CenterFuselage / lateral Panel definition between
mainframe2 und mainframe3
centerFuselageLongFloorBeamConnectionType
CenterFuselage / Long. floor beam connection
centerFuselageLowWingConfiguration
centerFuselageMainFramesType
CenterFuselage / main frame definition, containing
mainframe and pressure Bulkhead definitions
centerFuselagePressureFloorType
CenterFuselage / pressure floor definition between
mainframe2 und mainframe3
centerFuselagePressureFloorType
CenterFuselage / side box definition between mainframe2
und mainframe3
certificationCasesType
Change log
chargesCostType
Aerodynamic contributions of a chrordwise part within a wing segment strip
Contains a list of chordwise parts within a wing segment strip for which aerodynamic coefficients are specified
Aerodynamic contributions of a chordwise part within a within a wing segment strip
Describes the contributions of a specific par within a wing segment to the total aerodynamic coefficients of a wing segment strip
A chordwisePart describes the contributions of a specific chordwise part within a wing strip to the total aerodynamic coefficients of this strip.
It extends spatially between the two eta positions of the parent strip (see strip documentation)
and four xsi positions in the segment coordinate system.
As with the parent stips, only the trailing border (..ToSegmentXsi) of a chordwisePart is defined,
while the leading border always equals the trailing border of the preceding chordwisePart (or 0 for the first part).
To account for oblique trailing borders (e.g., to match the aileron on a tapered wing) two different toSegmentXsi positions can be defined,
one at the inner border (innerBorderToSegmentXsi) and one at the outer border (innerBorderToSegmentXsi) of the parent strip.
The innerBorderToSegmentXsi and outerBorderToSegmentXsi of the last chordwisePart must be equal to 1.
Chordwise coordinate xsi in the segment coordinate system to define the end position of the chordwisePart at the inner eta border
Chordwise coordinate xsi in the segment coordinate system to define the end position of the chordwisePart at the outer eta border
Class divider
Class divider element collection type
Class divider element for use in the decks
Class dividers
Class divider instance collection type.
Class divider
cockpitControlsType
Cockpit controls type, containing the cockpit controls
Some controls are mandatory, others can be added via
cockpitControl elements
cockpitControlType
single cockpitControl is defined by a pilotInput and a
commandOutput. The commandOutput is linked to the commandCase
Reference values for aerodynamic coefficients
Specification of reference values for aerodynamic coefficients.
Reference area
Reference length
Reference point
Reference translation
Reference rotation
Aerodynamic contributions of the components
Contains a list of components for which aerodynamic coefficients are specified
Aerodynamic contributions of a component
Describes the contributions of a specific component to the total aerodynamic coefficients
Reference to a component
Aerodynamic contributions of a wing segment
Describes the contributions of a specific wing segment to the total aerodynamic coefficients of a wing
It is obligatory to reference a segment via its uID and to provide its coefficients.
The breakdown of the coefficients comprises the strips and remainingContributions.
The latter must only be specified if strips is given.
Reference to a wing segment uID
Aerodynamic contributions of strips within a wing segment
Contains a list of strips within a wing segment for which aerodynamic coefficients are specified
Aerodynamic contributions of a strip within a wing segment
Describes the contributions of a specific strip within a wing segment to the total aerodynamic coefficients of a wing segment
The strip extends spatially between two eta coordinates (i.e., from an inner border to an outer border).
In order to avoid redundancy, the inner border (denoted as from) is always identical to the outer border of the previous strip (denoted by to).
Accordingly, only the to-border can be specified explicitly,
while the from-border equals implicitly either to 0 (for the first strip) or the toSegmentEta value of the previous element.
The toSegmentEta of the last strip must be equal to 1!
It is obligatory to provide the coefficients of the strip.
The breakdown comprises the chordwiseParts and remainingContributions.
The latter must only be specified if the breakdown into chordwiseParts is given.
This breakdown is optional.
If it is specified, but the sum of all chordwiseParts does not match the strip coefficients, one or more remainingContributions may be applied to
ensure consistency (sum of all chordwiseParts + sum of all remainingContributions must be equal to total strip coefficients).
Spanwise coordinate eta in the segment coordinate system to define the end of the strip
Aerodynamic coefficients breakdown
Breakdown of the total aerodynamic coefficients into contributions from the various vehicle componenents.
A detailed breakdown is only specified for the wing.
Other components, such as the fuselage, are more generically referred to as otherComponents.
Since the sum of the contributions within a breakdown must equal the total coefficients, the remaining contributions must be listed in remainingContributions.
The remainingContributions cannot be defined alone.
Either the definition of a wing, otherComponents or both together is valid and can be combined with remainingContributions.
Aerodynamic contributions of wing segments
Contains a list of wing segments for which aerodynamic coefficients are specified
Aerodynamic contributions of the wings
Contains a list of wings for which aerodynamic coefficients are specified
Aerodynamic contributions of a wing
Describes the contributions of a specific wing to the total aerodynamic coefficients of a vehicle
It is obligatory to reference a wing via its uID and to provide its coefficients.
The breakdown of the coefficients comprises the segments and remainingContributions.
The latter must only be specified if segments is given.
Reference to a wing uID
commandCaseCommandType
single commandCaseCommand can either hold a
controlFunction or a controlDistributor
commandCasesType
plural Element for commandCase, some fixed dp, dq, dr
and dx, dy, dz
commandCaseType
single commandCase Containing several
commandCaseCommands
UIDs of 2d structural fuselage elements
(e.g., pressure bulkheads, walls or
floors). The compartment will be
enclosed with the fuselage skin
The compartment defines an enclosed volume within the fuselage. It is defined by a set of border geometries. This could be pressureBulkheads, walls or floors and they are referred by their uIDs. The volume is closed with the fuselage skin. The geometry tool has to check, if the compartment definition gives a closed geometry.
The compartment defines an enclosed volume in the
fuselage. It is defined by a set of border geometries.
This could be pressureBulkheads, walls or floors and
they are referenced by their uIDs. The volume is closed
with the fuselage skin. The geometry tool has to check,
if the compartment definition gives a closed geometry.
Compartment geometry uIDs list.
Name of the compartment.
Description of the compartment.
Ideal design volume of the compartment.
complexBaseType
Base type for complex nodes (including external data
attributes)
componentCostType
componentSegmentPathType
Definition of hingePoint of the
componentSegment. The hingePoint is used as reference point for
the deflection definition.
Definition of the orientation of the hinge
line with three Euler-rotation angles. The hinge line is
oriented along the global y-axis if all rotations are 0.
Definition of all steps of the deflection
path.
componentSegmentStepsType
Definition of one step of the deflection path.
componentSegmentStepType
The control parameter is used to reference the
state of a control device, e.g. in the load
case description. Can have any value and is NOT limited to the
range of -1 to 1.
Translation along the x-, y- and z-Coordinate
of the rotated hinge coordinate system.
Rotation around the hinge line.
ComponentSegments of the wing.
ComponentSegments type, containing all the
componentSegments of the wing.
ComponentSegment of the wing.
Within componentSegments the wing structure, the
control surfaces, the wing fuel tanks and the
wingFuselageAttachment is defined by using relative coordinates.
A componentSegment is defined in the same way as
segments: from one cross section (sections->elements) to
another. Compared to segments one componentSegment can can start
and end at elements that are not consecutive. Therefore that one
componentSegment can be the combination of several segments.
Each wing has at least one componentSegment (from root to tip).
The maximal number of componentSegments equals the number of
segments (each segment is defined as one componentSegment).
This also implies that each segment can only be part of one componentSegment.
In principal a componentSegment can combine any number
of segments. But if in one section two elements are defined, the
componentSegment has to start/end there as no well-defined
relative coordinates can be defined if steps in the wing occur.
An example for wing componentSegments can be found in
the picture below:
Within componentSegments a relative spanwise
coordinate (eta) and a relative chordwise coordinate (xsi) is
defined. Those coordinates are used for the definition of e.g.
wing structures and control surfaces. there are two types of eta xsi coordinates.
Segment (eta, xsi) coordinates define the relative local coordinate system for a segment ranging from (0,0) to (1,1).
The eta xsi coordinates for a component segment are based on the segment eta xsi planes.
As a reference length for the component segment eta coordinate the
mid chord lines of all the segments are used.
The beginning of this line at from-element equals eta = 0, while the end of this line
at the to-element equals eta = 1. All wing positions that lie on the same
element (segment border) have the same eta coordinate. The points in between
two elements are defined by the iso xsi lines of the segment eta xsi space.
An example for the definition of the relative axes can
be found in the picture below:
In order to calculate the global coordinates of a component segment eta xsi point
one first has to calculate the eta point on the xsi iso line of (xsi=0.5),
and then walk along the iso eta lineof the segment.
An example for determining the a component
eta xsi point can be found in the picture below:
Name of the wing componentSegment.
Description of the componentSegment.
Reference to the element from which the
componentSegment shall start.
Reference to the element from which the
componentSegment shall end.
Description of deflection path of
componentSegments (e.g. used for
trimmable HTPs).
Components
Component
Name
Description
Link to pre-defined system element uID
Link to pre-defined system element uID
UIDs of the structural mounts as defined in the fuselages or wings (see structuralMountType for further details).
compositeLayerType
CompositeLayer type, containing data of a composite
layer
This type defines single composite layers by
giving a ply thickness, ply reference angle and a materialUID.
Name of layer
Description of layer
Thickness of layer
Angle of layer in degree
Material UID of the layer
compositesType
compositeType
Composite type, containing data of a composite
Within this type individual stackings of
composites can be introduced by defining an offset and a set of
composite layers. The order of the composite layers defines the
stacking order.
Name of composite
Description of composite
offset of the laminate. The reference plane of
the laminate is the arithmetic mean of the laminate thickness.
Vehicle configurations
List of vehicle configurations (e.g., setting of control surfaces, landing gear, etc.)
Vehicle configuration
Name
Description
Configurations
Configuration
UID of the configuration definition
Index of the weight and balance vectors to which the configuration applies to. [1;inf]
Configuration
Contains references to control control devices and (or) the global aircraft configuration node.
Reference to the aircraft configuration definition node (aircraft/model/configurationDefinitions/configurationDefinition)
State description of the control elements
connectivitiesType
connectivityType
Constraint
Specification of performance constraints.
Constraints allow vectors of double values to define parameter lapses within a mission segment.
The example below illustrates this by means of an exemplary climb profile of a conventional airliner, in which multiple physical and regulatory speed constraints are simultaneously specified over several altitudes
(e.g., to account for the crossover altitude):
<endCondition>
<positionGeo>
<altitude relationalOperator="ge" uID="altClimb">10058.4</altitude> <!-- FL330 -->
</positionGeo>
</endCondition>
<constraint>
<referenceEndConditionUID>altClimb</referenceEndConditionUID>
<endConditionRatio>0.0;0.303</endConditionRatio> <!-- FL0, FL100 -->
<continuitySetting>discrete</continuitySetting>
<CAS relationalOperator="le">128.61;154.33</CAS> <!-- 250 [kt], 300 [kt]-->
<machNumber relationalOperator="le">0.78;0.78</machNumber>
<prioritySetting>velocity</prioritySetting>
</constraint>
From FL0 until FL100, the vehicle should fly at a velocity less than or equal to CAS = 250 kt or M = 0.78. In this first segment at low altitudes, the constraint on CAS is triggered.
From FL100 until FL330, the vehicle should fly at a velocity less than or equal to CAS = 300 kt or M = 0.78. In this second segment, the vehicle starts by increasing velocity until 300 kt, the constraint on maximum machNumber triggers from the crossover altitude onwards
Reference to the uID of the segment end condition variable to which a profile of constraintSettings is provided
Vector indicating the ratios of the constraintSettings profile with respect to the provided referenceEndCondition, ranging from 0 to 1. If this vector is defined, the provided constraintSettings are expected to be vectors with the same length providing ratio-value pairs. Example: for referenceEndCondition <range><z> (i.e.: flown distance in z direction of the segment), a vector of <CAS> and <machNumber> is provided to define a climb profile.
Defines how to interpret the parameter lapses within the segment: discrete steps (C0 continuity) or linear interpolation (C1 continuity)
Calibrated airspeed within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Mach number within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Climb angle within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Rate of climb within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Specific excess power within the segment
(e.g.: for defining minimum SEP to
remain after step climbs have been
performed).
Altitude difference of each step climb
Flight heading at the end of the segment in compassAngle with reference to true North [deg]. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Total change of heading angle during segment (a full turn is 360 degrees) [deg]. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Rate of turn within the segment [deg/s]. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Thrust setting for derated engine as fraction of max. Thrust (e.g.: for powered descents, deceleration not at IDLE, manoevres). If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Rate of velocity within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Load factor experienced during segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Constant altitude of the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Priority setting indicating which constraint is preferred within the segment. If a vector is provided, a constraint profile is defined with respect to the <referenceEndCondition> using the <endConditionRatio> vector.
Mission segment constraints
Contains a set of constraints for the segment
Airfoil definition of an control surface at the
inner/outer border.
Optional definition of the exact airfoil shape at the
inner/outer border of the control surface.
The airfoil shape is defined via referencing to the
airfoilUID. As the leading and trailing edge point is fix due to
the outer shape definition of the control surface the airfoil
can only be rotated around the x-axis (axis going from leading
to trailing edge of the inner/outer border of the control
surface). Scaling in x-direction is also defined by the outer
shape, wherefore only scaling in y and z direction is allowed.
Reference to the airfoil uID.
Rotation around an axis, going from the
leading edge point to the trailing edge point of the inner/outer
border of the control surface. Defaults to 90°, which is
equivalent to perpendicular on the control surface middle plane.
Scaling of the airfoil in spanwise direction
(not used for 2D airfoils).
Scaling in thickness direction of the airfoil.
controlDistributorsType
plural Element for controlDistributor
controlDistributorType
single controlDistributor bundling several
controlElements
Within some analyses, it might occur that overlapping control element settings are specified.
In this case, it is assumed that a cumulative setting is built by summing up the individual settings.
As the behavior of these settings is not necessarily linear, a certain order of summation has to be followed:
The command inputs for each controlDistributor, coming from the configurationUID, as well as from separate settings have to be summed up to a total commandInput.
With this total commandInput, each corresponding controlDistributor definition has to be evaluated,
in order to get controlParameter settings for a number of controlDevices.
All controlParameter settings for a controlDevice, coming from the configurationUID ,
from the controlDistributors and from separate controlDevice settings have to be summed up to get a total controlParameter for each controlDevice.
With this total controlParameter, each corresponding controlDevice definition has to be evaluated, in order to find out what the control device finally is doing.
During the summation process (depending on the order of processing within step 1 to 4), commandInputs or controlParameters might exceed the specified limits for
that controlDistributor or controlDevices.
As an intermediate result, this should be accepted – however, when it comes to evaluation in step 2 and 4, all commandInputs and controlParameters have to be within the specified limits.
Vector of command inputs. The minimum and maximum value is given by the lowest and highest entry of the vector, respectively.
controlElementsType
plural Element for controlElement
controlElementType
Single controlElement linking the inputs of a controlDistributor via a gain
table to a control device by using its uID. Controls can be ControlSurfaces and in the
future thrust.
UID of the control device, e.g. a control surface. It is not allowed to reference another control distributor.
Vector of control device states resulting from the input commands. It must be of the same length as the inputCommands element.
The minimum and maximum values are defined according to the minimum and maximum values of the input commands.
controlFunctionsType
plural Element for controlFuntion
controlFunctionType
single controlFunction containing the controller's
parameters
Controllability requirements
Contains a list of controllability requirements
Controllability requirement
Name
Description
UID of point performance definition
UID of weight and balance description
controlLawModesType
Control Laws type, containing the aircraft's control
law modes
controlLawModeType
Control Laws type, containing the aircraft's control
law mode
controlLawsType
Control Laws type, containing the aircraft's control
laws
Definition of actuators of the control surface, that
are not placed within a track.
Definition of actuators of the control surface, that
are not placed within a track.
Definition of an actuator of the control surface, that
is not placed within a track.
Definition of an actuator of the control surface, that
is not placed within a track.
Reference to the actuator (actuator definition
currently not available in CPCAS, status 1.6).
Airfoil definition of an control surface between inner
and outer border.
Optional definition of the exact airfoil shape between
the inner and outer border of the control surface.
The airfoil shape is defined via referencing to the
airfoilUID. As the leading and trailing edge point is fix due to
the outer shape definition of the control surface the airfoil
can be rotated around the x-axis (axis going from leading to
trailing edge of the control surface) and around the z-axis
(normal axis on the control surface middle plane). Scaling in
x-direction is also defined by the outer shape, wherefore only
scaling in y and z direction is allowed.
Relative spanwise coordinate (eta) of the
control surface, where the leading edge of the airfoil is
placed.
Reference to the airfoil uID.
Rotation around an axis, going from the
leading edge point to the trailing edge point of the control
surface. Defaults to 90°, which is equivalent to perpendicular
on the control surface middle plane.
Rotation of the airfoil around the control
surface middle plane normal direciotn. Reference point is the
most forward point of the airfoil. Defaults to 90°, which is
equivalent to the airfoilplacement in flight direction (along
wings-x axis).
Scaling of the airfoil in spanwise direction
(not used for 2D airfoils).
Scaling in thickness direction of the airfoil.
Inner/outer border of the control surface.
Definition of the inner/outer border of the control
surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
In addition, optionally, the airfoil shape of the
control surface can be defined closer. For the leading edge
devices 'hollow'. If an exact control surface airfoil definition
should be used, outerShape->airfoils can be used.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Relative spanwise inner/outer position of the
leading edge of the control surface.
Relative spanwise inner/outer position of the
trailing edge of the control surface. Defaults to 'etaLE'.
Relative chordwise inner/outer position of
the trailing edge of the control surface. Reference is eta/xsi
from the parent.
Inner/outer border of the control surface.
Definition of the inner/outer border of the control
surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
In addition, optionally, the airfoil shape of the
control surface can be defined closer. For the
spoiler'relHeightLE' is used. If an exact control surface
airfoil definition should be used, outerShape->airfoils can
be used.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Relative spanwise inner/outer position of the
leading edge of the control surface. Reference is eta/xsi from
the parent.
Relative spanwise inner/outer position of the
trailing edge of the control surface. Reference is eta/xsi from
the parent. Defaults to 'etaLE'.
Relative chordwise inner/outer position of the
leading edge of the control surface. Reference is eta/xsi from
the parent.
Relative chordwise inner/outer position of the
trailing edge of the control surface. Reference is eta/xsi from
the parent.
Defines the relative high of lowest point of
the spoiler leading edge, relative to the airfoil height of the
parent at this position. See picture below.
Inner/outer border of the control surface.
Definition of the inner/outer border of the control
surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
In addition, optionally, the airfoil shape of the
control surface can be defined closer. For the trailing edge
device this is done at 'leadingEdgeShape', for the spoiler
'relHeightLE' is used and for the leading edge devices 'hollow'.
If an exact control surface airfoil definition should be used,
outerShape->airfoils can be used.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Relative spanwise inner/outer position of the
leading edge of the control surface. Reference is eta/xsi from
the parent.
Relative spanwise inner/outer position of the
trailing edge of the control surface. Reference is eta/xsi from
the parent. Defaults to 'etaLE'.
Relative chordwise inner/outer position of the
leading edge of the control surface. Reference is eta/xsi from
the parent.
Optional definition of the exact airfoil shape of the
control surface.
This type contains a list of control surfaces and their
deflection vectors
0. General overview
In this type, a list of control surfaces is defined.
1.
<controlSurface>
(mandatory)
One of these nodes per deflected control surface is
required here.
This type contains a vector of deflection values for a
single control surface
0. General overview
In this type, a vector of deflections of a single
control surface is specified.
1.
<controlSurfaceUID>
(mandatory)
A reference to a control surface from the aircraft
model
2.
<controlParameters>
(mandatory)
A vector of controlParameters of the selected
control surface (with respect to the defined deflection path).
Reference to a control surface
Control parameters of the control surface
controlSurfaceHingeMomentMapsType
controlSurfaceHingeMomentMapsType type, containing the
aerodynamic moment maps for one or more control surfaces.
controlSurfaceHingeMomentMapType
controlSurfaceHingeMomentMap type, containing a moment
map with aerodynamic data for a control surface. Array order is:
controlParameters min->max then angleOfAttack then angleOfSideslip
then reynoldsNumber then machNumber. AngleOfAttack, angleOfSideslip,
reynoldsNumber and machNumber are taken from the basic
performance map one level above.
Reference to the control surface
Control parameters of the control surface
Hinge point
The deflection path of a control surface is described with respect to two hinge points -
one at the inner border of the control surface and one at the outer border of the control surface.
These two points are defined by the xsi and relative height coordinates of the parent.
In addition, a translation (with respect to the wing coordinate system) can be applied.
Therefore they can also be defined outside of the control surface.
These two points define the hinge line, which is a straight line between them.
An example is shown below:
Relative chordwise coordinate (xsi) of the
hinge line point. Reference is the parent chord.
Relative height of the hinge line point.
Reference is the parent airfoil height.
Optional absolute translation of the hinge point.
This can be used to move the hinge points outside of the wing shape.
Outer shape definition of the control surface.
Definition of the outer shape of the leading edge
control surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Outer shape definition of the spoiler control surface.
Definition of the outer shape of the control surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Outer shape definition of the control surface.
Definition of the outer shape of the trailing Edge
control surface.
The position on the planform of the control surface is
defined by defining the eta/xsi coordinates of the inner/outer
and forward/rear border. The eta/xsi coordinates refer to the
parent.
Please find below an example for the definition of the
planform of a trailing edge device. Other controlsurfaces are
similar.
Definition of the deflection path of the control
surface.
The deflection path of a control surface is described
with respect to two hinge points - one at the inner border of
the control surface and one at the outer border of the control
surface. Those two points are defined using the xsi and relative
height coordinates of the parent. Therefore those points can also
lay outbound of the control surface. Those two points defined
the hinge line, which is a straight line between the two points.
The deflection path of the control surface is defined
within the hinge line coordinate system. This is defined as
follows: The x-hinge coordinate equals the wing x-axis. The
y-hinge coordinate equals the hinge line axis (see above;
positive from inner to outer hinge point). The z-hinge line is
perpendicular on the x-hinge and y-hinge coordinate according to
the right hand rule. The rotation of the control surface is
defined as rotation around the positive y-hinge line.
The deflection of the control surface is defined by at
least two steps. It is specified as follows:
First the x-deflection at the inner and outer border; afterwards
the z-deflection of the inner and outer border; last the
y-deflection of the inner border. The y-deflection is only
defined at the inner border, as it is identical to the outer
border. If no values for the outer border deflection are given,
they default to the values of the inner border.
An example can be found below:
controlSurfacePerformanceMapType
ControlSurfacePerformanceMap type, containing a delta
performance map with aerodynamic data for a control surface. Array
order is: relativeDeflection min->max then angleOfAttack then
angleOfSideslip then altitude then machNumber. AngleOfAttack,
angleOfSideslip, altitude and machNumber are taken from the
basic performance map one level above.
Reference to the control surface
Relative deflection of the control surface
controlSurfacePerformanceMaps
controlSurfacePerformanceMaps type, containing the
aerodynamic delta performance maps for one or more control
surfaces.
Border type for the inner and outer border of a wing
cut out
Maybe applied to specify inner and outer border of
the cutout either via eta or rib references
Link to a rib definition
Rib number in the corresponding
ribDefinitionUID
Spanwise location of the border at the
leading edge of the cut out
Spanwise location of the border at the
trailing edge of the cut out
Cut out of the parents upper/lower skin due to a
control surface.
Optional. Definition of the skin cut out due to a
control surface. The cut out of the skin can either be defined
by referencing to a spar uID or by defining the relative chord
values (xsi) of the cut at the inner and outer border of the
control surface. The xsi value is based on the parents chord.
For leading edge devices additional parameters can be defined.
An example for wing cut outs can be found in the
picture below:
Xsi value of the inner border, where the cut
out begins.
Xsi value of the outer border, where the cut
out begins.
Reference to a spar, defining the skin cut
out.
Definition of the steps of the control surface
deflection path.
List of steps.
controlSurfaceStepType
The deflection path of the control surface is defined
within the hinge line coordinate system. This is defined as
follows: The x-hinge coordinate equals the wing x-axis. The
y-hinge coordinate equals the hinge line axis (see above;
positive from inner to outer hinge point). The z-hinge line is
perpendicular on the x-hinge and y-hinge coordinate according to
the right hand rule. The rotation of the control surface is
defined as rotation around the positive y-hinge line.
The deflection of the control surface is defined by at
least two steps. It is specified as follows:
First the x-deflection at the inner and outer border; afterwards
the z-deflection of the inner and outer border; last the
y-deflection of the inner border. The y-deflection is only
defined at the inner border, as it is identical to the outer
border. If no values for the outer border deflection are given,
they default to the values of the inner border.
An example can be found below:
The control parameter links a generic floating point value to
a certain status of a control device (e.g. control surface, landing gear, suction
system, brake parachute, ...). See the documentation of the global CPACS-Element for
further information.
Translation of the inner hinge line point
within the hinge line coordinate system. Defaults to zero. Not
allowed for spoilers!
Translation of the outer hinge line point
within the hinge line coordinate system. Defaults to the values
of the inner hinge line point. Not allowed for spoilers!
Positive rotation around the hinge line,
heading from the inner to the outer border. Defaults to zero.
controlSurfacesType
Definition of the outer shape, structure and deflection
of all control surfaces (flaps, slats, soiler, ailerons...) of
the wing.
Control surface tracks (mechnaical link between control
surface and parent).
Control surface tracks (mechnaical link between control surface and parent).
A track generally describes the structural connection between a control surface and a wing (or parent element).
For example, a track can be a flap track, a revolute joint connecting an aileron or spoiler, or the kinematics of slats on a wing.
The spanwise position of the track is defined by etaPosition, which refers to the control surface dimensions.
The structural properties of the track (e.g. materials) are defined in trackStructure.
If an actuator is included into the the track, a reference is given in actuator.
The principal kinematic of the track is defined by setting the trackType and trackSubType.
Please refer to the tables below for setting the trackType and trackSubType parameter.
Note, those tables are not final - they are extended continuously.
Trailing edge track types
trackType
picture
description
trackSubType
picture
description
1
Revolute joint; no actuators; the revolute joint is on TED hinge line.
1
Revolute attached at the wings rear spar and the TEDs front spar respectively the load
carrying ribs of the TED.
2
Revolute joint; dropped hinge; linear or rotary actuator (subtype-dependent) included.
The drive strut (if any) is defined as strut1.
1
Box beam design as wing attachment; rotary drive attached at wing rear spar.
2
Wing attachment at wing rear spar; rotary drive attached at wing rear spar
3
Track mounted inside the fuselage at wing root.
3
Upside-down, forward link in conjunction with a straight track on a fixed structure
as aft. support; including rotary drive.
1
Wing attachment using a box beam design where track is mounted; rotary actuator mounted
at the wing rear spar.
2
Track mounted inside the fuselage at wing root.
4
Straight and sloped track on a fixed structure as forward support and an upright link as
aft. support; linear or rotary actuator (subtype-dependent) included.
1
Wing attachment using a box beam design where the track is mounted; rotary actuator at
the wing rear spar.
2
Wing attachment using a box beam design where track is mounted; rotary actuator mounted
on the track.
3
Track mounted inside the fuselage at wing root.
Relative chordwise position of the track. Eta
refers to the control surface.
Type of the track. Please refer to the remarks
of the controlSrufaceTrackTypeType for details.
Type of the track. Please refer to the remarks
of the controlSrufaceTrackTypeType for details.
Cut out of the parents structure due to a control
surface.
Optional. Definition of the parents structure cut out
due to a control surface. The cut out is split into three parts:
cut out of the upper and lower skin and the definition of an
profile connecting the cut out of the upper and lower skin.
An example for wing cut outs can be found in the
picture below:
In the default configuration the cut out is as wide as
the control surface. If additional spacing is necessary inner
and outer border may be set.
costAirConditioningSystemsType
costAutomaticFlightSystemsType
costAuxilaryPowerUnitsType
costBleedAirSystemsType
costCommunicationSystemsType
costComponentsType
costDeIcingSystemsType
costElectricalSystemsType
costEnginePylonsType
costEquippedEnginesType
costFireProtectionSystemsType
costFixedEmergencyOxygenSystemsType
costFlightControlSystemsType
costFuelSystemsType
costFurnishingElementsType
costFurnishingsType
costFuselagesType
costHydraulicSystemsType
costInstrumentSystemsType
costLandingGearType
costLightingSystemsType
costNacellesType
costNavigationSystemsType
costPowerUnitsType
costSystemsType
costWaterInstallationSystemsType
costWingsType
crashLoadCasesType
crashLoadcaseType
CrashLoadcase type, containing a crash loadcase
Optional start of crash section: Default:
first frame of model
Optional end of crash section: Default: last
frame of model
Initial velocities
Initial rotations around axes, roll, pitch,
yaw
Initial rotational velocities around axes
Definition of reference point to consider
rotation
AccelerationFields, usually gravity in z
Definition of impact Surface for crash
simulation
crewCostType
crossBeamAssemblyPositionType
CrossBeamAssemblyPosition type, containing the position
of a crossBeam assembly
UID of profile based structural element to be
used as crossbeam
UID of the frame to which the crossbeam is
attached
Referenze z position of the crossbeam
crossBeamStrutAssemblyPositionType
CrossBeamStrutAssemblyPosition type, containing a
crossBeam strut assembly position
UID of profile based structural element to be
used as crossbeam strut
UID of the frame to which the crossbeam strut
is attached
UID of the crossbeam to which the crossbeam
strut is attached
Referenze y position of the strut at the
crossbeam intersection
angle of the strut in global yz plane
cruiseRollersType
Definition of one cruise rollers/mid-span
stops.
cruiseRollerType
Definition of the position of the mid point of
the roll of the cruise roller.
Definition of the attachment of the cruise
roller to the parent of the flap. This is the track on which the
roll rolls during retracted flap position
Definition of the attachment of the cruise
roller to the flap.
Degree of freedom that is blocked by the
cruise roller if the flap is in retracted position. Positive =
cruise roller blocks bending in the direction of the upper skin
of the parent. Negative = cruise roller blocks bending in the
direction of the lower skin of the parent.
cst2DType
A 2D implementation for Class shape
transformations. For more details look at AIAA Journal of Aircraft
Vol.45 No.1 2008
The psi vector for definition of the class and
shape function, i.e. the points at which the CST functions will
be evaluated
N1 for the class function for the upper side
of the profile
N2 for the class function for the upper side
of the profile
B Coefficients for the Bernstein polynominal
on the upper side
N1 for the class function for the lower side
of the profile
N2 for the class function for the lower side
of the profile
B Coefficients for the Bernstein polynominal
on the lower side
Optionally, the trailingEdgeThickness of the
profile
Maps points (actually the index in the point list) to a curve parameter.
Which parameters are allowed depends on the context.
For example in a wing profile, values between -1 and 1 are valid.
List of indices of points to be mapped. Each index must be in the range [1, npoints].
List of parameters on the curve, that is mapped to the points defined by their index.
A curve that interpolates a list of points.
The curve interpolates the list of points, typically with a b-spline.
In theory, the interpolation is somewhat ambiguous as it is not defined at which
curve parameter a point will be interpolated.
To solve is ambiguity, an optional parameter map can be defined
that maps point indices with curve parameters.
Kinks can also be modeled by populating the "kinks" array with the
indices of points that should be on a kink. As an example, look at the following image:
In this example, the kinks array will be "3;7".
Optionally, the parameters of the kinks can be set in the parameter map.
The whole profile looks as follows:
<pointList>
<x>...</x>
<y>...</y>
<z>...</z>
<kinks>3;7</kinks>
<parameterMap>
<pointIndex>3;5;7</pointIndex>
<paramOnCurve>0.2;0.5;0.8</paramOnCurve>
</parameterMap>
</pointList>
Indices of points at which the curve has a kink. Each index is in the range [1, npoints].
Map between point index and curve parameter.
curvePointType
Point on a curve in normalized curve coordinates.
The referenceUID must reference a one-dimensional curve such as spars.
Relative position on the referenced line/curve.
This reference uID determines the reference curve.
If it points to a spar, then the eta value is considered to be a spar coordinate
between start (eta=0) and end (eta=1) of the spar.
cutLoadIntegrationPointsType
cutLoadIntegrationPoints are defined in a vector
notation, due to the high amounts of data. Usually they well be
defined in between the ribs. Each point must have an id.
Optionally it is possible to rotate the orientation within a
cutloadIntegrationPoint to obtain meaningful results. The
orientation is optional and relative to the CPACS coordinate
system
cutOutControlPointsType
Additional definition of the leading edge cut out.
Optional. Definition of additional parameters,
describing the shape of the parents leading edge of the cut out
due to leading edge devices.
The parameters are described in the picture below:
Relative height of the most forward position of
the parents leading edge, relative to the airfoil height without
cut out.
Relative chordwise position of the most
forward position of the parents leading edge, relative to the
parents chord without cut out.
Definition of cut out profiles.
Definition of cut out profiles.
Optional, the exact shape between the upper and lower
skin cut out can be given by using cutOutProfiles. In general
cut out profiles are open profiles and not closed profiles as
e.g. wing airfoils. The placement, scaling and (partly) rotation
of the cut out profiles is fixed as the beginning and ending
point of the profile is fixed as can be seen in the two pictures
below.
Reference to the profile uID. Profiles should
be linked in profiles/structuralProfiles
Relative spanwise position of the cut out
profile. The eta coordinate refers to the control surface and
describes the cut out profile at the leading edge of the control
surface.
Rotation of the airfoil around the control
surface middle plane normal direciotn. Reference point is the
most forward point of the airfoil. Defaults to 90°, which is
equivalent to the airfoilplacement in flight direction (along
wings-x axis).
cutOutType
CutOut type, containing cut-outs
Name of the cut out element
Description of the cut out element
Width of the cut element (absolute value)
Height of the cut element (absolute value)
Fillet radius of the cut element (absolute
value)
UID of a structural element that reinforces
the cut out
Damping derivatives for positive and negative rotation
rates
0. General overview
This type contains the damping derivatives. They are
split up into those derivatives for positive rotation rates,
and those for negative rotation rates.
1. <positiveRates> (optional)
Damping derivatives, calculated by positive rotation
rates.
2. <negativeRates> (optional)
Damping derivatives, calculated by negative rotation
rates.
Damping derivatives for positive and negative rotation rates
0. General overview
This type contains the damping derivatives. They are
split up into those derivatives for positive rotation rates,
and those for negative rotation rates.
1. <positiveRates> (optional)
Damping derivatives, calculated by positive rotation
rates.
2. <negativeRates> (optional)
Damping derivatives, calculated by negative rotation
rates.
Damping derivatives
This type contains aerodynamic performance maps with
the damping derivatives. The derivatives are calculated using
rotational rates [rad/s], normalized by:
Rate*ReferenceLength/flow speed. The rotations are performed
around the global axis directions with the aircraft model's
global reference point as origin. The damping derivative
performance maps are vectors of the same length as the input
vectors of the baseline aerodynamic performance maps, consisting of
semicolon separated values.
Change of cd by normalized roll rate
Change of cd by normalized pitch rate
Change of cd by normalized yaw rate
Change of cs by normalized roll rate
Change of cs by normalized pitch rate
Change of cs by normalized yaw rate
Change of cl by normalized roll rate
Change of cl by normalized pitch rate
Change of cl by normalized yaw rate
Change of cmd by normalized roll rate
Change of cmd by normalized pitch rate
Change of cmd by normalized yaw rate
Change of cms by normalized roll rate
Change of cms by normalized pitch rate
Change of cms by normalized yaw rate
Change of cml by normalized roll rate
Change of cml by normalized pitch rate
Change of cml by normalized yaw rate
damTolBehaviourType
Damage tolerance law, Walker approach
Damage tolerance law, Forman approach
damTolFormanType
Parameter Kc [Pa m^0.5]
Parameter C2 [m/cycle]
Parameter m2 [-]
damTolWalkerType
Fracture toughness KIc [Pa m^0.5]
Parameter C0 [m/cycle]
Parameter m [-]
Parameter gamma [-]
dateBaseType
Base type for date nodes (including external data attributes).
This date type is based on the xsd:date definition.
"To specify a time zone, you can either enter a date in UTC time by adding a "Z" behind the date - like this: 2002-09-24Z
or you can specify an offset from the UTC time by adding a positive or negative time behind the date - like this:
2002-09-24-06:00
or
2002-09-24+06:00" (description taken from http://www.w3schools.com/xml/schema_dtypes_date.asp)
dateTimeBaseType
Base type for dateTime nodes (including external data
attributes)
Deck component
Name
Description
UID of the corresponding element in the cpacs/vehicles/deckElemets node
Deck component
Name
Description
UID of the corresponding element in the cpacs/vehicles/deckElemets node
Deck doors
Deck door
doors describe all doors of the cabin. They are linked
to a structural door description. The cabin door is usually equal
in size to the door, but does not need to be. The structural door
might describe a wider cut-out, while the cabin door is primarily
intended for evacuation modeling and cabin layout. In order to
obtain a 3-dimensional door representation, the local cabin
geometry shall be used.
Name
Description
Number of passengers this door adds to the
overall exit capacity limit of the aircraft.
Opening geometry of the door
Door type (boarding, cargo, evacuation or service)
Deck elements
A list of predefined elements which can be linked in the actual deck of the aircraft or rotorcraft model via referencing its uID.
Ceiling panel elements for use in the decks
Class divider elements for use in the decks
Galley elements for use in the decks
Generic floor elements for use in the decks
Lavatory elements for use in the decks
Luggage compartment elements for use in the decks
Seat elements for use in the decks
Sidewall panel elements for use in the decks
Cargo container elements for use in the decks
Deck
Data of an aircraft or rotorcraft deck
Name
Description
UID of the object used as parent coordinate system (typically the fuselage uID)
UID of the floor structure which supports this deck
The reference point of the deck/cabin. In a
conventional aircraft like the A320, it would be the rear wall
of the cockpit. The transformation is relative to the parent object
defined by “parentUID”, which should be the fuselage.
Deck type: passanger, VIP, cargo or livestock
Seat modules
Aisles
Spaces
Sidewall panels
Luggage compartments
Ceiling panels
Galleys
Generic floor modules
Lavatories
Class dividers
Cargo containers
Doors
Structural mounts
Structural mount type containing the structural connections of cabin elements
Structural mount
Structural mount type containing the structural connections of cabin elements
Name
Description
UID of the component to connect to
Decks
List of decks
deltaTemperatureType
Design masses
The design mases are requerments which can com form the
TLARs
Take off mass
Zero Fuel mass
Maximum landing mass
Maximum ramp mass (the maximum weight
authorised for the ground handling)
Design parameters list
Contains a list of all design parameters.
Design parameter definition
Contains a the values of a parameter and its uid as reference.
Design space definition
Contains the definition of the design space.
Design study definitions
Contains the data of design studies definitions.
directOperatingCostType
divergenceCasesType
DivergenceCases type, containing the cases for
aeroelastic divergence analysis
divergenceCaseType
DivergenceCase type, containing a case for aeroelastic
divergence analysis
Mach number of divergence case
Divergence stagnation pressure
Dome Type
doorAssemblyPositionType
DoorAssemblyPosition type, containing the position of a door
assembly
optional definition of door type (restricted to pax,
service, emergency, cargo)
UID of the door element
description
UID of the forward door frame
UID of the backward door frame
UID of the stringer at the upper door
edge
UID of the stringer at the lower door
edge
Lower height of the door with respect to the floor.
(Information necessary for boarding and evacuation analysis not
necessarily linked to structures)
Minimum widh of the door element. (Information
necessary for boarding and evacuation analysis not necessarily
linked to structures)
Minimum height of the door element. (Information
necessary for boarding and evacuation analysis not necessarily
linked to structures)
Door on right side of the fuselage = 1; on the left =
-1. (Information necessary for boarding and evacuation analysis not
necessarily linked to structures)
doorCutOutType
CutOut type, containing cut-outs
Name of door cutout element
Description of door cutout
element
Fillet radius of door cutout
element
Reference UID to the description of a DSS (door
surround structure)
doorOpeningLegacyType
doors describe all doors of the cabin. They are linked
to a structural door description. The cabin door is usually equal
in size to the door, but does not need to be. The structural door
might describe a wider cut-out, while the cabin door is primarily
intended for evacuation modeling and cabin layout. In order to
obtain a 3-dimensional door representation, the local cabin
geometry shall be used.
This is the forward x-coordinate of the door
relative to the cabin origin.
the door sill height relative to cabin origin.
The width of the door in x-direction.
the effective height of the door.
"doorOpeningType"
Ceiling panel instance collection type.
doorsType
Doors type, containing doors
doorSurroundStructurePositionType
DoorSurroundStructurePosition type, containing the position of a
door surround structure
number of bays effected by DSS in front of
door
number of bays effected by DSS in behind of
door
number of bays effected by DSS
number of bays effected by DSS
doorSurroundStructuresAssemblyType
doorSurroundStructuresAssembly type, containing
dorrSurroundStructure definitions
Array with semicolon separated values of type double
In
CPACS
arrays are used to exchange values
in full-factorial parameter spaces, for example to describe the aerodynamic coefficients depending
on Mach number and altitude.
Thus, the dimensions of the array are spanned by the input vectors. See the following
example where two input vectors are defined. For clarification the entries of the array result from
the multiplication of the index values of the corresponding input vectors:
<inputVector1>1;2;3</inputVector1>
<inputVector2>4;5;6;7</inputVector2>
<array>4;5;6;7;8;10;12;14;12;15;18;21</array>
Any entries of type
double
separated by semicolons are valid, e.g.:
<doubleArrayTest>123.456;+123.456;-1.234e56;-.45E-6;NaN;0</doubleArrayTest>
<doubleArrayTest>123.456</doubleArrayTest>
<doubleArrayTest>123.456,+1234.456</doubleArrayTest>
<doubleArrayTest>123.456;mainWingUID</doubleArrayTest>
<doubleArrayTest>1234.4E 56;-1.234e5.6</doubleArrayTest>
Please note that the syntax of arrays in the current
CPACS
version correspond exactly to the syntax of vectors. There is no special character indicating
the dimensions. Thus, the input vectors have to be determined from the documentation of the
corresponding elements and splitting of the one-dimensional vector has to be done manually.
doubleBaseType
Base type for double nodes (including external data
attributes)
The double base type can include optional uncertainty
information. The description of uncertainties is placed in
additional attributes. First, it is described by an attribute
that describes the type of uncertainty function called
functionName. The functionName attribute includes the tag name
of the distribution function which is listened in the table
shown below. Each uncertainty function is further describes by a
set of parameters that are described in the table below.
doubleConstraintBaseType
Base type for double nodes including a relational operator attribute indicating valid constraint region
The doubleConstraintBaseType extends the doubleBaseType and thus inherits all its attributes.
Vector with semicolon separated values of type double
Any entries of type
double
separated by semicolons are permitted, e.g.:
<doubleVectorTest>123.456;+123.456;-1.234e56;-.45E-6;NaN</doubleVectorTest>
<doubleVectorTest>123.456</doubleVectorTest>
<doubleVectorTest>123.456,+1234.456</doubleVectorTest>
<doubleVectorTest>123.456;mainWingUID</doubleVectorTest>
<doubleVectorTest>123.456;1234.4E 56;-1.234e5.6</doubleVectorTest>
doubleVectorConstraintBaseType
Base type for double vectors including a relational operator attribute indicating valid constraint region.
The doubleVectorConstraintBaseType extends the doubleVectorBaseType and thus inherits all its attributes.
Drag contributions
The drag contributions relate to different physical mechanisms. The sum of the contributions does not have to be equal to the total drag.
Drag contributions due to the displacement of the flow around a component. Zero for irrotational two-dimensional flows.
Drag contributions due to shear forces on surfaces
Drag contributions due to friction
Drag contributions due to energy loss through vortex structures caused by the pressure difference between the upper and lower sides of three-dimensional lifting surfaces.
Drag contributions due to mixing of streamlines between airframe components (e.g., interaction between wing and fuselage or pylon and wing).
Drag contributions due to energy dissipation in shock waves
Drag contributions due to trimmed aircraft configuration
driveSystemsType
DriveSystems Type, containing all the drive systems
(combination of transmissions/gearboxes and shafts and their
links to engines and rotors) of a rotorcraft model.
driveSystemType
DriveSystem Type, defining a drive system (combination
of transmissions/gearboxes and shafts and their links to engines
and rotors) of a rotorcraft model.
Duct assembly
Name
Description
UID of part to which the duct is
mounted (if any)
Duct structure
Ducts
Duct
Name
Description
dynamicAircraftModelAnalysisType
Electric motors
Electric motor
Electric power
Electric power values
Direct current voltage [V]
Electric power
Electric power value
Direct current voltage [V]
Geometry
Mass
Description of mass, center of gravity and inertia. Density should only be specified in combination with a valid geometry.
Density
Mass
Center of gravity (x,y,z)
Ellipsoid dome
Half axis fraction
Emissivity map, containing the diffuse emissivity of a material at different spectral lengths.
The emissivity of a material can vary with the spectral wave length.
The vectors diffuseEmissivity and waveLength must have the same size to be valid.
The data should be linearly interpolated.
Wave length in [m]
Diffuse emissivity of the material
Emtpy element
Base type for string nodes (including external data
attributes)
Energy Carriers
engineAnalysisType
Thrust at takeoff
Fan pressure ratio at takeoff
Bypass ratio at takeoff
overall pressure ratio at takeoff
Maximum rotations per second, shaft 1
Maximum rotations per second, shaft 2
Design tip relative mach number (FAN)
DryMass of engine
Definition of global geometry parameters of the engine
fan.
Inner radius of the fan.
Outer radius of the fan.
Definition of the global engine geometry.
All engine geometry definitions refer to the engine
coordinate system. The engine coordinate system has its orgine
in the middle of the fan plan. The positive x-axis is heading to
the rear, the positive z-axis to the top and the y-axis
according to the right hand rule.
length of engine
diameter of engine
dProp
Chordlength of a fan blade
engineGlobalType
EngineGlobal type, containing global engine data
Concept of engine
Year of first certification
Rotation direction of the engine if looking at
it from the front, i.e. from propeller/fan to exhaust
Hub to tip ratio
Number of rotor blades of fan
Number of outlet guiding vanes
Rotor stator spacing (relative to chordlength)
List of all engine mounts.
Definition of one engine mount.
Name of the engine mount.
Description of the engine mount.
position of the engine mount referring to the
engine coordinate system.
UID of the engine mount.
Engine nacelle
The engine nacelle is part of an engine.
It allows to define the outer geometry of the following engine components:
Fan cowl
Core cowl
Center cowl
All geometric values refer to the fan position.
The common use case for this definition includes bypass engines.
In the case of non-bypass engines, the core cowl should be omitted.
Fan cowl
Core cowl
enginePerformanceMapsType
enginePerformanceMapType
EnginePerformanceMap type, containing a performance map
with engine data
Flight Level
Mach number
Absolute thrust [N]
Fuel mass flow
Speed at core engine nozzle
Total temperature at core engine nozzle
Mass flow through core engine nozzle
Speed at bypass nozzle
Total temperature at bypass nozzle
Mass flow through bypass nozzle
Percent of n1Max, shaft 1
Percent of n2Max, shaft 2
Fan pressure ratio
Fan efficiency
Turbine entry total temperature
Emission index Carbon Monoxide
Emission index Nitrogen Oxide
Emission index Sulfur Oxide
Emission index Soot
Emission index unburned hydrocarbon
air density at core outlet 8
air density at bypass outlet 18
area at core outlet
area at bypass outlet
Engine references
EnginePositions type, containing a reference to the
used engines and their positions at the configuration
enginePositionType
EnginePosition type, containing data for a single
engine
Name of the engine
Description of the engine
Reference to the used engine
Component, to which the engine is mounted
Engine pylons
Definition of one engine pylon.
Name of the engine pylon.
Description of the engine pylon.
UID of the parent (normally wing or fuselage).
UID of the engine pylon.
Rotors
Propeller
Definition of the engine spinner geometry.
Most forward x-position of the spinner.
X-position of the spinner base.
Radius of the spinner at the base position.
Engines
Engines type, containing complete engine configurations
engineType
Engine type, containing engine data.
Name of engine
Description of engine
Scaling of engine take-off thrust
Environmental conditions
Specification of environmental conditions
Delta temperature with respect to the standard temperature of the selected atmosphere [K]
etaIsoLineType
Iso line described by point of the same eta coordinate.
Can be either segment or component segment coordinates.
Relative spanwise position. Eta refers to the segment or componentSegment depending on the referenced uID.
This reference uID determines the reference coordinate system.
If it points to a segment, then the eta value is considered to be in segment
eta coordinate; if it points to a componentSegment,
then componentSegment eta coordinate is used.
Point in eta and xsi coordinates
Point described by eta-xsi coordinates.
Can be either segment or component segment coordinates.
Relative spanwise position. Eta refers to the segment or componentSegment depending on the referenced uID.
Relative chordwise position. Xsi refers to the segment or componentSegment depending on the referenced uID.
This reference uID determines the reference coordinate system.
If it points to a segment, then the eta-xsi values are considered to be in segment
eta-xsi coordinates; if it points to a componentSegment,
then componentSegment eta-xsi coordinates are used.
Relative height at eta, xsi position
Point described by eta-xsi and a relative height coordinate.
Can be either segment or component segment coordinates.
If relHeight is not given, the point has no offset from the eta-xsi plane
Relative spanwise position. Eta refers to the segment or componentSegment depending on the referenced uID.
Relative chordwise position. Xsi refers to the segment or componentSegment depending on the referenced uID.
Relative height position.
relHeight is relative to the local airfoil thickness.
This reference uID determines the reference coordinate system.
If it points to a segment, then the eta-xsi values are considered to be in segment
eta-xsi coordinates; if it points to a componentSegment,
then componentSegment eta-xsi coordinates are used.
fatigueBehaviourType
Fatigue law, stress based Brown Miller approach [N/m^2]
fatigueStressBasedBrownMillerType
Parameter sigma_f [N/m^2]
Parameter b [-]
Parameter epsilon_f [-]
Parameter c [-]
fleetType
Each fleet can be divided into sub fleet groups
Name of fleet
Description of the fleet
Description of sub-fleets.
flightAnalysisType
Flight dynamics
Linear model parameters
Trim result
Mach number
True airspeed
Angle of attack
Altitude
Flight envelope speed
Specification of the V-speed
Vector with altitudes
Vector with True Airspeeds
Flight Envelopes
Specification of flight envelopes
Flight Envelope
Specification of a flight envelope
Offset from temperature of the atmospheric model [K]
Flight load cases
Load conditions
Inertia load conditions acting on the aircraft
Description
Safety factor applied on the loads
Rotational rates around centre of gravity
Enumeration flag stating the typ of the load
case (i.e. limit or ultimate loads)
Angle of sideslip [deg]
Angle of attack [deg]
Flight loads
Loads resulting from the load case analysis
Flight path
Definition of a flight path by points of longitude, latitude and a descriptive waypoint code.
Vector of waypoint codes. If waypoint codes are not available put empty items into the waypoint string
Vector of waypoint latitude values in [deg]
Vector of waypoint longitude values in [deg]
Indicates the type of the way point.
Performance cases
List of performance cases
Performance case
Name
Description
UID of flight performance requirement
Results of the landing analysis
Determined landing distance.
Determined ground phase distance.
Level flight
Specific excess power
Flight performance requirements
Contains a list of flight performance requirements
Flight performance requirement
Name of the performance case
Description of the performance case
Reference to the considered weightAndBalance case
The UID of the mission to be flown
List of point performance uIDs constraining the mission
Results of the take-off analysis
Main element containing the results for
take-off calculations optimized for min-imum liftoff speed
VLOFmin.
Main element containing the results for
take-off calculations optimized for min-imum safety speed V2min.
Turn
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Flight Cases
flightPointType
Flights
Flighs type, containing all flight definitions
Flight systems
flightType
Flight type, containing data of a scheduled flight
MissionUID for the flights mission definition
ModelUID of the aircraft appointed to perform the flight
Departure day of the flight
Time of departure - the time is defined as SOBT (Scheduled Off-Block Time) / STD (Scheduled Time of Departure)
Arrival day of the flight
Time of arrival - the time is defined as SIBT (Scheduled In-Block Time) / STA (Scheduled Time of Arrival)
Reference to the operating airline of a flight
floorPanelsType
FloorPanels type, containing floor panel definitions
floorPanelAssemblyPositionType
FloorPanelAssemblyPosition type, containing a floor
panel assembly position
x coordinate of the begin of the floor panel
(absolute value)
x coordinate of the end of the floor panel
(absolute value)
UID of the first long. floor beam to be
connected to the floor panel
UID of the second long. floor beam to be
connected to the floor panel
UID of structural sheet element used for the
floor panel
Flying qualities
Provides a list of flying qualities cases
Flying qualities case
Name
Description
Aircraft Class; Class 1 small light aircraft;
Class 2 medium weight aircraft, low to medium maneuverability;
Class 3 large, heavy aircraft, low to medium maneuverability;
Class 4 high maneuverability aircraft
Flight Phase Category; Category A Non-terminal
flight phases requiring maneuvering, precision tracking, or
precise flight-path control (e.g. air-to-air combat, terrain
following). Category B Non-terminal Flight Phases with gradual
maneuvers and without precision tracking, although accurate
flight-path control may be required (e.g. climb, cruise).
Category C Terminal Flight Phases are normally accomplished
using gradual maneuvers and usually require accurate flight-path
control (takeoff, approach and landing).
main element containing longitudinal transfer
functions
main element containing lateral directional
transfer functions
main element containing characteristic
parameters of the handling qualities criteria
main element containing handling qualities
ratings
fqCharParametersType
static margin [-]
main element containing characteristic
parameter of phugoid damping
main element containing characteristic
parameters of short period mode criteria
main element containing characteristic
parameters of roll oscillation criterion
coupling of roll and spiral mode: normal = no
coupling of roll and spiral mode coupled = coupling of roll and
spiral mode
main element containing characteristic
parameters of lateral eigenvalues
main element containing characteristic
parameters of effective roll time constant criterion
main element containing characteristic
parameters of roll performance criterion
fqEiglatType
natural frequency of dutch roll mode [rad/s]
damping of dutch roll mode [-]
roll time constant [s]
time to double of spiral mode [s]
ratio of bank to sideslip angle [-]
natural frequency of coupled rollspiral motion
[rad/s]
damping ratio of coupled roll-spiral motion
product of roll-spiral damping and natural
frequency [rad/s]
handling qualities level of roll time constant
handling qualities level of roll spiral mode
fqLateralType
numerator of transfer function roll control
surface deflection to bank angle
numerator of transfer function roll control
surface deflection to yaw rate
numerator of transfer function roll control
surface deflection to sideslip angle
numerator of transfer function roll control
surface deflection to bank angle of reduced 4th order system
numerator of transfer function roll control
surface deflection to sideslip angle of reduced 4th order system
numerator of transfer function yaw control
surface deflection to yaw rate
numerator of transfer function yaw control
surface deflection to sideslip angle
numerator of transfer function roll stick
input to roll rate
numerator of transfer function roll stick
input to yaw rate
numerator of transfer function roll stick
input to bank angle
numerator of transfer function roll stick
input to sideslip angle
numerator of transfer function pedal input to
roll rate
numerator of transfer function pedal input to
yaw rate
numerator of transfer function pedal input to
bank angle
numerator of transfer function pedal input to
sideslip angle
denominator of lateral motion
denominator of lateral motion of reduced 4th
order system
fqLongitudinalType
numerator of transfer function pitch stick
input to pitch rate
numerator of transfer function pitch control
surface deflection to pitch angle
numerator of transfer function pitch stick
input to pitch angle
numerator of transfer function pitch stick
input to angle of attack
numerator of transfer function pitch stick
input to vertical load factor
denominator of longitudinal motion
fqPhugoidType
damping ratio of phugoid mode [-]
time to double amplitude of unstable phugoid
mode [s]
fqRatingsType
handling qualities level of phugoid damping
handling qualities level of C* criterion
main element containing handling qualities
levels of short period mode
main element containing handling qualities
levels of roll oscillation criterion
main element containing handling qualities
levels of lateral eigenvalues
handling qualities level of effective roll
time constant
handling qualities level of roll performance
fqRollPerfType
time to reach critical bank angle [s]
critical bank angle that has to be reached
[deg]
fqRoloscType
ratio of oscillatory component of the roll
rate to the average roll rate [-]
phase angle of dutch roll oscillation in
sideslip [deg]
phase angle between roll rate and sideslip in
dutch roll mode [deg]
ratio of first minimum roll rate to first
maximum [-]
handling qualities level of ratio of
oscillatory component of roll rate to average roll rate
fqShortPeriodType
steady state normal acceleration change with
angle of attack [g/rad]
short period natural frequency of reduced
order system [rad/s]
short period damping ratio of reduced order
system [-]
equivalent pitch time delay of reduced order
system [s]
handling qualities level of CAP criterion
fqTreffType
effective roll time constant [s]
time where tangent of bank angle step response
is placed [s]
framesAssemblyType
FramesAssembly type, containing frames assembly
frameType
frame type, containing frame definition (V1.5+)
freePathType
Frustum
The component coordinate system of the frustum is centered on the center of its geometrically defining variables,
which is half the height and center of the lower and upper circular faces.
The upper radius is optional.
If not specified, it defaults to the lower radius, resulting in a cylinder.
Upper radius [m]
Height [m]
Upper radius [m] (if not defined: equals lowerRadius)
Fuel flows
Fuel flow
Fuel Mass Fraction
Describing the mass fraction considered for a mission segment sequence
Reference to the segment from which the fuel fraction should be considered
Reference to the segment to which the fuel fraction should be considered
Float value of the mass fraction defined as
fraction = m_end / m_start
Storage conditions
Fuels
Definition of different volumes of the fuel tank.
Theoretical volume if material thicknesses
(ribs, spars, skins, stringers) and systems (fuel pumps,
pipes...) are neglected.
Usable fuel volume aircraft operations.
Total real fuel tank volume.
Factor between the usalbe fuel volume and
the real fuel volume.
Factor between the real fuel volume and the
theoretical optimum fuel volume.
Fuel
Name
Description
Type of energy carrier
Lower heating value
Density at 15deg C
CO2 emission index
H2O emission index
N2 emission index
Energy specific cost
Freezing point
fuselageAeroPerformanceType
fuselageAeroPerformance type, containing performance
maps with aerodynamic data of a fuselage.
Reference to the uID of the analysed fuselage
References used for the calculation of the
force and moment coefficients of the fuselage (in the fuselage
axis system!)
Calculated aerodynamic performance maps of the
fuselage
fuselageCutOutsType
fuselageCutOuts type, containing fuselage cutouts
fuselageCutOutType
fuselageCutOut type, containing a fuselage cutout
definition
Name of the cutout
Description of the cutout
X position of the cutout center point
Y offset of the cutout reference point
Z offset of the cutout reference point
Angle in degrees of the vector pointing from
the cutout reference point to the cutout center point, measured
relative to the direction of the fuselage z axis.
Coordinates of the unit vector defining the
direction of extrusion
Coordinates of the unit vector defining the
y-axis of the local cutout coordinate system. Must be normal to
the orientationVector.
This value is used to define the width of the
cutout
This value is used to define the height of the
cutout
This value is used to define the width of the
cutout
This value is used to define the height of the
cutout
Fillet radius of the cut element (absolute
value)
Cutout type. Determines the type of the cutout
and how it is treated by the tools. Possible values:
("window"|"door"|"ramp")
fuselageElementsType
FuselageElements type, containing the elements of a
fuselage section
fuselageElementType
FuselageElement type, containing fuselage element data
Name of fuselage element
Description of fuselage element
Reference to a fuselage profile
List of fuel tanks
The fuselage fuel tank geometry is defined by a link to a fuselage geometry compartment.
The fuel tank volume type should also be used for the wing fuel tank
fuselageProfilesType
FuselageProfiles type, containing fuselage profile
geometries. See profileGeometryType for further documentation
fuselagesAeroPerformanceType
fuselagesAeroPerformance type, containing
fuselagesAeroPerformance
fuselageSectionsType
FuselageSections type, containing fuselage sections
fuselageSectionType
FuselageSection type, containing fusleage section and
element data
Name of fuselage section
Description of fuselage section
fuselageSegmentsType
FuselageSegments type, containing fuselage segment
definitions (from sections and elements)
fuselageSegmentType
FuselageSegment type, containing data of a fuselage
segment
Name of fuselage segment
Description of fuselage segment
Reference to element from which the segment
shall start
Reference to element at which the segment
shall end
Optional and additional guidecurves to shape
the outer geometry.
Structural mounts
fuselageStructureType
FuselageStructure type, containing data of the fuselage's
structure
Fuselages
Fuselages type, containing the fuselages of the
configuration
fuselageType
Fuselage type, containing all data related to a
fuselage
Name of fuselage
Description of fuselage
UID of part to which the fuselage is
mounted (if any)
Galley elements
Galley element collection type
Galley element for use in the decks
Galley element
Galley element type, containing the base elements of the cabin
Number of trolleys
Galleys
Galley instance collection type.
Galley
Gas turbines
GasTurbine
Gear boxes
Gear box
This type contains a list of gears and their deflection
vectors
0. General overview
In this type, a list of gears is defined.
1.
<gear>
(mandatory)
One of these nodes per deflected gear is required
here.
This type contains a vector of deflection values for a
single gear
0. General overview
In this type, a vector of deflections of a single
gear is specified.
1.
<gearUID>
(mandatory)
A reference to a gear from the aircraft model
2.
<controlParameters>
(mandatory)
A vector of control parameters of the selected
gear
Reference to a gear
Control parameters of the gear
stringerFramePositionType
stringerFramePosition type, containing individual
stringer / frame position definition (CPACS V2.1+)
Continuity definition for profile extrusion:
0= C0 (allows sharp edges, default), 2= C2 (defines curvature
continuity)
Definition of interpolation between different
profiles: 0= no interpolation 1= interpolation of structural
profile
generalStructuralMembersAssemblyType
generalStructuralMembersAssembly type, containing
structural member assemblies
generalStructuralMemberType
Generators
Generator
Generic components
genericCostType
Generic floor elements
Generic floor element collection type
Generic floor element for use in the decks
Generic floor modules
Generic floor module instance collection type.
Generic floor module
Global design parameters
Inner radius of the cylinder
Inner length of the cylinder
Generic fuel tank
Cryogenic tank
Name
Description
Volume
Burst pressure
genericGeometricComponentType
In some cases additional geometric components need to
be linked to a CPACS, but these components are not yet handled by
CPACS explicitly. For example, a belly fairing and/or external
tanks.
A generic geometric component may be applied to include
such a geometry from an external file (preferably STEP) in the
context of the overall aircraft.
Name of genericGeometricComponent
Description of genericGeometricComponent
UID of part to which the component is mounted
(if any)
Generic geometric components
Generic geometry component
Mass description
parentUID not set
parentUID set
location without refType
global
local
location with refType="absLocal"
global
local
location with
refType="absGlobal"
global
global
Note: The combination of location with refType="absLocal" and no parentUID is global,
because the local coordinate system to which the location is referring to via refType equals the global coordinate system.
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wingUID
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wingUID
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wingUID
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Name
Description
UID of the component which serves as parent element, i.e. whose coordinate system is to be used as a reference for the mass properties (CoG location, orientation and massInertia). Thus, two cases can occur: (1)
it is set: local coordinate system of the parent; (2) it is not set: global CPACS coordinate system.
UID of the geometric description of the component.
Mass [kg]
Mass location.
If the optional refType attribute is set, it explicitly specifies whether the location of the mass refers to the global CPACS coordinate system (absGobal) or the local coordinate system of the parent element (absLocal, given by the CPACS hierarchy OR by parentUID).
If it is not set, the global CPACS coordinate system is considered as default.
To ensure consistency, the same settings apply as well to orientation and massInertia.
Orientation. The reference coordinate system (absGlobal or absLocal) is identical to location.
Mass inertia. The reference coordinate system (absGlobal or absLocal) is identical to location.
genericSystemsType
Node for geometrical layout of system components
based on simple geometric shapes
Generic system
Name
Description
geographicPointConstraintType
Geographic point constraint, containing a longitude, latitude, altitude data triplet.
Longitude coordinate 0-360
Latitude coordinate 0-360
Altitude in meters
geographicPointType
Geographic point type, containing a longitude, latitude, altitude data triplet.
Longitude coordinate 0-360
Latitude coordinate 0-360
Altitude in meters
airfoilAeroPerformanceType
airfoilAeroPerformance type, containing performance maps
with aerodynamic data of an airfoil.
References used for the calculation of the
force and moment coefficients
Calculated aerodynamic performance maps of the
full configuration
globalBeamPropertiesType
globalBeamPropertiesType, containing the global beam
properties such as EA, EI, mass
Flight point
Mach number
Calibrated air speed
True air speed
Performance Cases
Specification of performance cases required for the performance evaluation of air vehicles (aircraft, rotorcraft, etc.).
The information in this node is generally applicable to any kind of vehicle.
Vehicle-specific information is provided through the performanceRequirements node found under:
/cpacs/vehicles/../model/performanceCases.
Ground load Cases
guideCurveProfileGeometryType
A guide curve profile is defined by a profile name, an
optional description and a 3-dimensional relative pointlist with
all three coordinates mandatory. For typical profiles, one of
the coordinate vectors contains only "0" entries. All point
coordinates are transferred to the global coordinate system.
First and last point may, but need not to, be identical.
The points have to be ordered in a mathematical
positive sense.
A profile can be symmetric. In that case the profile
is interpreted as being not closed and will be closed by
mirroring it on the symmetry plane.
Curves have to go continuously over the whole wing or
fuselage
Connection of guide curves from segment to segment
Please note, currently it is not possible to apply any
means of class based transformation in the description. However,
this may be an addition for the future.
Name of profile
Description of profile
guideCurveProfilesType
Guide Curve Profiles type. This type is used to
describe guide curves that enable designers to create a geometry
that deviates from a standard loft.
Guide Curves Type
Guide Curve type. This type is used to describe guide
curves that enable designers to create a geometry that deviates
from a standard loft.
Guide Curve Type
A guide curve may be used to alter the shape of the
outer geometry and "guide" the loft.
The guide curve profiles are defined in the guideCurveProfileGeometryType.
Their use on wing and fuselage components is illustrated in the image below.
Name of guide curve
Description of guide curve
Reference to a guide curve profile
For the first segment fromGuideCurveUID is not
a valid entry! For the first guideCurve
fromRelativeCircumference must be applied! fromGuideCurveUID is
exclusive.
Reference to the previous guide curve from
which this guide curve shall start.
Continuity definition for geometry
generation. Possible options: C0, C1 from previous, C2 from
previous, C1 to previous, C2 to previous
Reference to the relative circumference
position from which the guide curve shall start. Valid values
are in the interval -1.0...1.0.
Reference to the parameter
position from which the guide curve shall start. Valid values
are in the interval -1.0...1.0.
Tangent at first point
The relative circumference
position at which the guide curve shall end. Valid values
are in the interval -1.0,..,1.0.
The parameter
position at which the guide curve shall end. Valid values
are in the interval -1.0...1.0.
Tangent at last point
Local direction along which the relative x-coordinates of
the guide curve points are defined. For the wing the default is
the wing's local x-axis, for the fuselage its the fuselage's local z-axis.
CPACS header
Header type, containing CPACS dataset description
Name of CPACS dataset
Description of CPACS dataset
Version of initial CPACS dataset according to the Semantic Versioning 2.0.0 standard.
DEPRECATED: Should only be set to allow TiGL to open the file until TiGL is adopted accordingly.
Will be replaced by the cpacsVersion element in versionInfos.
Heat exchangers
Heat exchanger
Heat flow
Heat flow value
Heat flow
Heat flow value
hingeMomentsMapType
hingeMomentsMap type, containing a hinge moments map
with aerodynamic data. Array order is: angleOfAttack min->max
then angleOfSideslip then reynoldsNumber then machNumber.
All coefficients in the aeroperformanceMap relate to
the CPACS coordinate system. See documentation of the
CPACS-Element for further information.
Name of the AeroPerformanceMap.
Description of the AeroPerformanceMap.
Mach number
Reynolds Number
Sideslip angle
Angle of attack
htpFwdInterfaceDefType
Definition of the interface of forward HTP attachment
Definition of the forward HTP attachment
interface
relative width of reinforcement at fwd HTP
attachment, between 0.0 and 1.0
relative width of plate at fwd HTP attachment
(only applicable for Type1 model), between 0.0 and 1.0, smaller
than htpPlateWidth
UID of panel element at HTP forward attachment
in x-direction (shell elements)
UID of panel element at HTP forward attachment
in z-direction (shell elements)
UID of reinforcements for panel element at HTP
forward attachment in z-direction (beam elements)
UID of the element to fix HTP to fuselage
(beam elements)
htpInterfaceDefType
Definition of the interface of HTP
Definition of the HTP interface
UID of the fuselage frame at the forward HTP
attachment
UID of the fuselage frame at the backward HTP
attachment
maximum HTP deflection (nose up in
degrees)
maximum HTP deflection (nose down in
degrees)
angle of the reinforcements at backward HTP
attachment
(in degrees)
Defines area (absolute) in x-direction around
htpFrame2UID where the HTP attachmentpoint has correct position
==> check and potentially warning message
Defines area (absolute) in y-direction around
the
outer edge of htpFrame2UID where the HTP attachmentpoint has correct
y-position ==> check and potentially warning
message
Defines allowed z-position for rear HTP
attachment
relative to total frame height ==> check and potentially warning
message ==> check and potentially warning
message
Definition of HTP structural
elements
Definition of HTP forward attachment to
structure
htpStructElemDefType
definition of structural elements in HTP attachment
Definition of tailplane attachment area
(Standard Configuration)
UID of structural element for HTP front
crossbeams
UID of structural element for HTP rear
crossbeams
UID of structural element for HTP diagonal
beams
UID of structural element for HTP side beams
UID of structural element for upper HTP cutout
reinforcement beams, also used for lower cutout reinforcement,
when not explicitly defined
UID of structural element for lower HTP cutout
reinforcement beams (optional)
Skin Layers
Structure
Hulls
Hulls
Name
Description
indirectOperatingCostType
Individual system categories
Generic
integerBaseType
Base type for integer nodes (including external data
attributes)
List of fuselage fuel tanks integrated in compartments.
The integral fuel tank geometry is defined by a link to a fuselage geometry compartment.
The fuel tank volume type should also be used for the wing fuel tank
Definition of one fuel tank integrated in a fuselage compartment.
The definition of fuselage tanks is still preliminary.
Currently, there is no link to any structural elements
Name of the fuselage fuel tank.
Description of the fuselage fuel tank.
Link to the tank geometry defined by a compartment.
interConnectionStrutAttachmentType
Definition of the position of the attachment
joint in relative coordinates.
Material settings of the attachment.
interconnectionStrutsType
Definition of one interconnection strut.
interconnectionStrutType
uID of control surface where this flap is
attached to by the interconnection strut.
Material settings of the strut (if strut is
modeled as a simple strut).
Definition of the attachment on this control
surface.
Definition of the attachment on the other
control surface
Free path in positive (tensil) and negative
(compression) direction before interconnection strut blocks.
intercostalPositionType
intercostalPosition type, containing the position of intercostals
in DSS
UID of the frame at which intercostal
starts
UID of the forward door frame
UID of the door
non-dimensional value ranging between 0 and 1
UID of profileBasedStructuralElement used for
intercostal
IntercostalsAssemblyType
IntercostalsAssembly type, containing intercostal
definitions
structuralElementsConnectionsType
StructuralElementsConnections type, containing
connections between structural elements
Flag for automatic generation of interface
definitions (draft version)
Isotensoid dome
Radius of the fitting/smaller polar opening
Isotropic material properties
Defines the material properties for an isotropic material. Note that the shear modulus G
is defined in terms of the elastic modulus E and the Poisson's ratio nu as:
Specifying a value for all three properties E, G and nu therefore results in an overdetermined material definition and must be avoided.
Young's modulus [N/m^2]
Shear modulus [N/m^2]
Poisson's ratio
Thermal expansion coefficient [1/K]
Thermal conductivity of the material in
[W/(m*K)]
Allowable stress for tension [N/m^2]
Allowable stress for compression [N/m^2]
Allowable stress for shear [N/m^2]
Allowable strain for tension
Allowable strain for compression
Allowable strain for shear
Yield strength, tension [N/m^2]
Yield strength, compression [N/m^2]
Plastification curves for isotropic
materials incl. element elimination
Optional knockdown factor for fatiuqe
(defaults to 1)
Fatigue behaviour of the material
Damage tolerance behaviour of the
material
Landing gear base
Base type for landing gears (i.e. nose gear, main gear and skid gear).
An example of a nose and main gear is shown below:
Name
Description
UID of the parent component. If set, the position of the main strut is defined relative to the parent coordinate system.
Total length of landing gear, equals the distance from the middle of the bogie/axles to the axis of rotation of the pintle strut. Distance is measured while landing gear is fully extended and in airborne condition (i.e., if a spring is present, the totalLength includes the springDeflectionLength)
Static suspension travel means the positive distance between the total length in airborne condition and the reduced length due to compression on the ground.
Compressed suspension travel means the positive distance between the total length in airborne condition and the maximum reduced length due to maximum compression on the ground (e.g., landing shock).
Transformation with respect to the uppermost point of the main strut. From this point the landing gear is oriented in negative z-direction by default.
Braking function
Describes the braking state of the landing gear.
Control parameter indicating that the brake is set
Control parameter indicating that the brake is released
Assembly of landing gear components
Describes an assembly of the various landing gear components
Main strut
Drag strut (Assumption: one end of the strut will connect to the main strut and the other end will be given as endPoint)
Landing gear control functions
A list of functions which can be addressed by the controlDistributor.
Extension path
Steering path
Braking state
Landing gear control parameters
Parameters of a landing gear control such as extraction or steering.
Retraction angle of the main landing
gear. Equals a rotation around the
global z-axis in degrees. 0 = retraction
to the front; 90 = retraction to the
left; 180 = retraction to the rear; 270
= retraction to the right.
Distance of the center of rotation to the top of the main strut
for retracting and extending the landing gear. I.e., a value of
0 means that the landing gear will rotate around the upper end
of the main strut during retraction. If this value is greater
than 0, the center of rotation is shifted by this value above
the main strut end point (translation along the main strut axis).
Extension step
Describes a step with the extension path of the landing gear. Make sure to provide a least one step with stepType=extracted!
Step type (retracted or extracted)
Control parameter
Extension angle of the main strut [deg]
Extension path
Describes the extension path of the landing gears via a list of steps.
Step within the extension path
landingGearInterfaceDefinitionsType
CenterFuselage landing gear interface definitions
keelbeamType
HighWingCenterFuselage / Keelbeam definition between
mainframe1 und mainframe2
lateralPanelsType
HighWingCenterFuselage / lateral Panel definition
between mainframe1 und mainframe2
longFloorBeamConnectionType
HighWingCenterFuselage / Long. floor beam connection
centerFuselageMainFramesType
High wing main frame definition, containing mainframe
UIDs
pressureFloorType
High Wing Center Fuselage / pressure floor definition
between mainframe1 und mainframe2
sideboxType
HighWingCenterFuselage / side box definition between
mainframe1 und mainframe2
Landing gear position safety margins
LandingGearPositionSafetyMargins type, containing the
safety margins of the gear due to its position
Safety margin for landing gear x position
regarding tail clearance at takeoff pitch angle
Safety margin for landing gear x position to
avoid tail dropping down during touchDown and ground maneuvering
Safety margin for landing gear y position to
avoid wing tip dropping down during ground maneuvering
Safety margin for landing gear y position
regarding wingtip or engine nacelle clearance at a certein roll
angle
Steering step
Describes a step with the steering path of the landing gear.
Step type (centered, fullBackboard or fullStarboard)
Control parameter
Steering angle [deg]
Steering path
Describes the steering path of the landing gears via a list of steps.
Step within the steering path
Definition of the wing attachment
Definition of the wing attachment, if
attached to the wing. The definition
includes the position of the landing gear as
well as the information to which spars resp.
supportBeam the gear is attached.
UID of the second spar, where the landing gear is attached to. Only used, if the landing gear is attached between two spars.
UID of a set of ribs (ribDefinition)
Number of the rib in the rib set (ribDefinition)
UID of the structural mount
Landing gears
Contains a list of landing gears.
Definition of the main landing gear support beam
position
Definition of the main landing gear support beam
position
Relative chordwise coordinate (xsi) of the
inner end of the support beam. The eta
position of the inner end is defined by the eta position of the
wing root (=wing-fuselage attachment).
Relative spanwise coordinate (eta) of the
outer end of the support beam. The xsi
coordinate of the outer end is defined by the spar position
(first spar), where the support beam is attached to.
Landing gears
LandingGear type, containing the definition of nose,
main and skid gears.
Lavatories
Lavatory instance collection type.
Lavatory
Lavatory elements
Lavatory element collection type
Lavatory element for use in the decks
Definition of the wings leading edge devices.
Definition of the wings leading edge devices.
Trailing edge device of the wing.
A leadingEdgeDevice (LED) is defined via its outerShape
relative to the componentSegment. The WingCutOut defines the area
of the skin that is removed by the LED. Structure is similar to
the wing structure. The mechanical links between the LED and the
parent are defined in tracks. The deflection path is described
in path. Additional actuators, that are not included into a
track, can be defined in actuators.
Leading and trailing edge are defined by the outer
shape of the wing segments, i.e. the trailing edge of a
trailingEdgeDevice is the trailing edge of the wing. This is also
valid for kinks that are present in the wing but not explicitly
modeled in the control surface.
The edges of the control surface within the wing are a
straight line in absolute coordinates! Hence, there needs to be a
straight connection between the eta-wise outer and inner points
of the edge that is within the wing in absolute coordinates.
Name of the leading edge device.
Description of the leading edge device.
UID of the parent of the LED. The parent is
the componentSegment, where it is attached to.
Optional definition of the airfoil inner shape of
leading edge devices (LED).
All parameters are optional. For the definition of the
parameters, please refer to the picture below. Parameters from
the outer border default to the parameters of the inner border.
Relative height of the most forward point of
the LED's rear part, based on the airfoil height of the parent
at this position. Optional.
Relative chordwise position of the most
forward point of the LED's rear part, based on the chord of the
parent at this position. Optional.
Optional definition of the leading edge shape of
trailing edge devices (TED).
All parameters are optional. For the definition of the
parameters, please refer to the picture below. Parameters from
the outer border default to the parameters of the inner border.
Relative height of the leading edge of the TED,
based on the airfoil height of the parent at this position.
Optional.
Relative chordwise upper skin position, of the
border, where the airfoil of the TED is equivalent of the
airfoil from the parent. Measured from the rear to the front (0
= TED trailing edge; 1 = TED leading edge). Values form the
outer border default to the value of the inner border. Optional.
Relative chordwise lower skin position, of the
border, where the airfoil of the TED is equivalent of the
airfoil from the parent. Measured from the rear to the front (0
= TED trailing edge; 1 = TED leading edge). Values form the
outer border default to the value of the inner border. Optional.
linerType
Liner type, containing liner data
Type of liner
% of fan diameter
% of fan diameter
Link to file (Step, Iges or Stl)
Please provide a link to the additional file that shall
be loaded by the TIGL library. Furthermore it is necessary to
provide the format attribute so that the file type can be
identified. Several CAD formats provide multiple endings, and
hence, this measure seems necessary.
Load analysis
Load application points
Multiple sets of scattered load application points can be defined. However, no specific information about the corresponding loads (e.g. whether aerodynamic or structural loads are involved) or mesh topologies are specified here, as such assumptions are tool-specific.
Load application point set
A point set contains discrete spatial points at which loads are applied (e.g., aerodynamic or structural loads). A typical procedure in CPACS is as follows:
Reference a wing, fuselage or control surface by its uID using the componentUID node.
Define a reference axis through the above component with the loadReferenceLine element to specify where a load distribution shall be applied.
Compute the intersections with (e.g.) ribs of the referenced component (wing, fuselage or control surface) and write the results into loadApplicationPoints.
This procedure results from common practice where the forces in structural analyses are typically introduced at structural elements such as ribs and spars.
With respect to preliminary aircraft design a two-dimensional load distribution is preferred.
However, an arbitrary distribution of the load application points is possible (without the intersection of structural elements with a reference axis in the previous step), for example to define discrete load distributions on the wing surface in streamwise and spanwise direction.
Specify the location and orientation of cut loads in the cutLoadIntegrationPoints element and the corresponding connectivity information in the connectivities node.
UID of a wing, fuselage or control surface
Reference axis (line) for load distribution
List of points at which load vectors are
applied to
List of points at which cut loads are applied to
Specification of connectivity properties between points
dynamicAircraftModelCoordinatesType
loadBreakdownType
Accelerations
Translational or rotational accelerations acting
on the aircraft
Rotational accelerations acting around aircraft centre of gravity [deg/s^2]
Gust definition
The coordinate system of the gust corresponds to the CPACS coordinate system.
Parameters describing the shape of the gust
Angle between gust and vehicle [deg] (e.g., 0deg: from right to left; 90 deg: downwards; 180deg: from left to right; 270/-90deg: upwards)
Gust length: length of ramp or gradient distance of 1-cos gust
Gust velocity
Load factors
Load factor in x-direction
Load factor in y-direction
Load factor in z-direction
Load case specification
Input values defining a load case
Environment
Altitude above sea level
Mach number
UID of the aerodynamic loads (aeroCase)
Controller description. Note: Since there is no controller description in CPACS yet, the expected content of this string element has to be defined individually for each project.
UID referencing the mass state of aircraft for this load case
Load cases
Load case superposition
List of uIDs referencing load cases that are superimposed to the current load case
UID reference to another load case to be superimposed
Load case
This node defines the load case
Name of the load case
Description of the load case
Load envelopes
The loads envelope is the results of the loadsAnalysis
and lists those loadcases that are limiting for the design
Load envelope
List of load cases defining a load envelope
Name
Description
UID of the corresponding point set
List of uIDs defining the loads envelope
loadReferenceAxisPointsType
loadReferenceAxisPointType
Relative spanwise position. Eta refers to the segment or componentSegment depending on the referenced uID.
Relative chordwise position. Xsi refers to the segment or componentSegment depending on the referenced uID.
Relative height position.
relHeight is relative to the local airfoil thickness.
This reference uID determines the reference coordinate system.
If it points to a segment, then the eta-xsi values are considered to be in segment
eta-xsi coordinates; if it points to a componentSegment,
then componentSegment eta-xsi coordinates are used.
Load sets
A list of load sets
Load set
A set of forces and moments
Description
UID of load application point set (analysis/global/loadApplicationPoints)
Force in x-direction [N]
Force in y-direction [N]
Force in z-direction [N]
Moment around x-axis [Nm]
Moment around y-axis [Nm]
Moment around z-axis [Nm]
Nodal displacement in x-direction [m]
Nodal displacement in y-direction [m]
Nodal displacement in z-direction [m]
Nodal rotation around x-axis [deg]
Nodal rotation around y-axis [deg]
Nodal rotation around z-axis [deg]
Load brake-down
Log entry
Description of CPACS dataset
Timestamp
Creator (tool, person, etc.)
logFloorBeamPositionType
longFloorBeamPosition type, containing individual
position definition
UID of structural element
UID of crossbeam to which the long. beam is
attached
y position of long. beam
Continuity definition for profile extrusion:
0= C0 (allows sharp edges, default), 2= C2 (defines curvature
continuity)
Definition of interpolation between different
profiles: 0= no interpolation 1= interpolation of structural
profile
longFloorBeamsAssemblyType
longFloorBeamsAssembly type, containing long. floor
beam assemblies
longFloorBeamType
longFloorBeam type, containing a long. floor beam
definition
Luggage compartment elements
Luggage compartment element collection type
Luggage compartment element for use in the decks
Luggage compartments
Luggage compartment
Additional Center Tanks
Additional center tank
Main actuator
Definition of the landing gear main actuator.
Reference to the main actuator uID of the
landing gear
Main landing gear
List of main gears
mainStrutInterfaceDefinitionsType
HighWingCenterFuselage main strut interface definitions
mainStrutFuselageAttachmentType
HighWingCenterFuselage / main strut attachment to
fuselage frame and stringer
reference to the structural element that comprises this connection.
maintenanceCostType
mAirConditioningType
Air conditioning mass description
Mass breakdown
1. General
The massBreakeDown is subdivided in designMasses,
fuel, payload and mOME (operating empty mass).
designMass
The design masses contain the overall values for mTOM and so forth.
These should be listed as specified by the TLAR or found from initial sizing.
fuel and payload
The fuel and payload nodes should contain maximum
values, i.e. full fuel tanks, all passengers on board and full
cargo holding. These values may exceed the maximum allowable
take-off mass as the actual loading of the aircraft should be
specified in the weight and balance section of the aircraft.
mOEM
The operation empty mass structure is based on the Airbus Mass Standard brake down [AIRBUS MASS STANDARD 2008].
The operator’s mass empty (OME) is defined by the sum of the following component masses:
operator’s items
manufacturer’s mass empty (MME)
2. massDescription
Each sub component has the following massDescription which include a:
Name
Description
parentUID
Mass value
Mass location
Mass orientation
Mass Inertia.
The massdescription can be found at the designMasses direct under each item.
At the fuel, payload and mOME under massDescription in each item and sub item.
Concerning symmetry please note that any item
referenced by its UID, e.g. wingUID, accounts for the complete
component, e.g. right and left side. Hence for these items
their complete mass needs to be specified. If the mass of
geometricallly symmetrical components is different, please use
the symmetry modifyers for UIDs: _symm and _mirror. See also
the overall CPACS definition section on symmetry
Mass composition
Mass flow
Mass flow value
Mass flow
Mass flow value
Mass inertia
massInertiaType
massInertiaVectorType
materialDefinitionForProfileBasedPointType
MaterialDefinitionForProfileBased type, containing a
material definition (Reference to material and thickness) for
profile based objects, addition point reinforcements
uID of the profile point to which the
additional stiffness shall be applied.
uID of a material definition.
cross sectional area of additional long.
stiffener at strctural element point
optional auxiliary parameter for special use
(no physical meaning)
optional auxiliary parameter for special use
(no physical meaning)
Definition of the properties of the structural
profile sheet
MaterialDefinitionForProfileBased type, containing a
material definition (Reference to material and thickness) for
profile based objects.
UID of the sheet to which the material
properties shall be applied
Predefined ID of the sheet of a standard profile
Length of the sheet of a standard profile [m]
uID of a composite definition.
Orthoropy direction of the composite.
Scaling factor of the composite thickness.
uID of a material definition.
Absolute thickness of the material [m]
Material Definition
MaterialDefinition type, containing a material
definition (Reference to material and thickness)
choice between composite / isotropic material
definition
uID of a composite definition.
Orthotropy direction of the composite.
Scaling factor of the composite thickness.
Absolute thicknesses are defined in each composite material
separately
uID of a material definition.
Absolute thickness of the material.
Materials
Materials type, containing material and composite data.
A material describes the properties of a certain material.
Several materials can be combined within one composite.
Material
Definition of the material properties for one of the following
material types:
isotropic materials
anisotropic 2D and 3D materials
orthotropic 2D and 3D materials
The nonemclature is adopted from [1] to define the material properties in an orthotogonal 1-2-3
coordinate system. This may be illustrated by the stresses of a three-dimensional cube:
[1] R. M. Jones, Mechanics Of Composite Materials, 2 New edition. Philadelphia, PA: Taylor and Francis Inc, 1998.
Name of the material
Description of the material
Material density [kg/m3]
Reference temperature for thermal expansion
coefficient [K]
mAutomaticFlightSystemType
Automatic flight system mass description
mAuxillaryPowerUnitType
Auxiliary power unit masse description
Axle
Axle mass description
mBellyFairingsType
mBleedAirSystemType
Bleed air system mass description
Bogie
Bogie mass description
mBulkCargosType
mBulkCargoType
mBulkheadsType
mCabinFloorsType
mCabinLightingsType
mCargoFloorsType
mCargoLiningsType
mCargoLoadingsType
Cargo masses
Cargo masses description
Cargo mass description
mCarriagesType
mCarryOnsType
mCarryOnType
mCateringsType
mCellsType
mCockpitLightingsType
mCommunicationType
Communication mass description
mComponentSegmentsType
mComponentSegmentType
mControlSurfaceSupportsType
mControlSurfaceSupportType
mCrewMembersType
mCrewSeatsType
mDeIcingType
De-icing mass description
mDocumentsToolsType
mDoorsType
Mechanical power
Mechanical power value [W]
Torque [Nm]
Force [N]
Mechanical power
Mechanical power value [W]
Torque [Nm]
Force [N]
mElectricalDistributionType
Electrical distribution mass description
mElectricalGenerationType
Electrical generation mass description
mEmergencyEquipmentsType
mEmergencyOxygenSystemsType
mEmptyULDsType
mEmptyULDType
Engine APU oils
Engine APU oil
mEngineControlType
Engine control mass description
mEquippedEnginesType
Equipped engines mass description
mExtLightingsType
mFireProtectionType
Fire protection mass description
mFixedGalleysType
mFixedLeadingEdgesType
mFixedLeadingEdgeType
mFixedTrailingEdgesType
mFixedTrailingEdgeType
mFlightControlsType
Flight controls mass description
mFloorCoveringsType
mFramesType
mFreshWaterSystemsType
Fuel in tanks
mFuelSystemType
Fuel system mass description
Fuel mass
Fuel mass description
Mass
Furnishing mass description
mFuselagesStructureType
Fuselages structure mass description
mFuselageStructureType
Fuselage structure mass description
Generic fuel tanks
mHydraulicDistributionType
Hydraulic distribution mass description
mHydraulicGenerationType
Hydraulic generation mass description
In-flight entertainment systems
mInstrumentPanelType
Instrument panel mass description
mInsulationsType
mIntegratedModularAvionicsType
Integrated modular avionics mass description
mInterGasSystemType
Inter gas system mass description
Mission definitions
General description
Specifies mission profiles required for the performance evaluation of air vehicles (aircraft, rotorcraft, etc.).
The missionDefininitions node is constructed in such a way, that all civil aircraft missions and missions from MIL-STD-3013A can be specified.
>
Hierarchical buildup of the mission definition
The mission definition is built-up in a hierarchical way. As the topmost element of the hierarchical mission definition, missions are created within the missions node.
Here, one or more segmentBlocks are referenced. These again link to a sequence of segments, making up parts of the missions:
<missions>
containing the <startCondition> and a sequence of <segmentBlockUIDs>
<segmentBlocks>
grouping multiple <segments> and providing overall information concerning the block of segments:
constraints in the form of an endCondition or given flightPath,
variableSegments and the corresponding variableConditions
in case a segment should be adjusted such to meet the segmentBlock's endCondition,
fuelPlanningType
(designFuel, reserveFuel , additionalFuel),
segmentDirection and numberOfRepetitions.
<segments>
containing detailed information per segment:
EITHER
segmentType,
endConditions,
constraints,
environmentalConditions
OR
massFraction
OR
mass
startConditions, constraints, endConditions and the relationalOperator attribute
the startCondition is provided at the mission node. Each subsequent segmentBlock/segment ends by the provided endCondition.
<startCondition>
start condition of the mission (can be an airfield or mid-air condition)
<endCondition>
specific end condition for a segmentBlock or segment (e.g.: an altitude or velocity)
<constraint>
specific performance settings for a segmentBlock or segment (e.g.: a cruise Mach number)
attribute
@relationalOperator
Indicate how conditions should be interpreted:
enum: „lt“, „le“, „eq“, „ne“, „ge“, „gt“
Examples:
0.78
1800
]]>
Example implementation for a civil transport mission
In the figure above, an example for a civil aircraft transport mission is provided.
The mission starts at a position of 0, 0, 0 with 0 velocity, as provided by the of the mission node.
Furthermore, the environmental conditions are provided: ISA atmosphere with a deltaTemperature of 0 [K].
The mission consists of three segmentBlocks: a designMission, reserves and the taxiIn segmentBlock.
example mission
this is an example mission
0.0
0.0
0.0
0.0
ISA
0.0
designMission
reserves
endPhase
]]>
The designMission segmentBlock is shown below.
It provides a set of five segments, together making up a mission with a range of 1000 [nm] or 1852 [km]. The “cruise” segment is the variable segment, which thereby should have a range of:
1852000 – range(climb) – range(descent), provided the taxiOut and takeOff segments are not providing any range credit.
The fuel burned during this segmentBlock should be added to the designFuel, the segmentDirection is provided for illustration purposes.
design mission
segment block for the design mission
1852000
cruise
range
designFuel
outbound
taxiOut
takeOff
climb
cruise
descent
]]>
The first and second segment are providing input for the part of the segmentBlock that doesn’t need simulation.
During the taxiOut phase, 50 [kg] of fuel is burned.
The takeOff phase has a duration of 30 [sec].
taxi out
taxi out segment
massFraction
50
take off
take off segment
takeOff
00:00:30
]]>
The rest of the segments make-up the flying part of the designMission.
The climb phase, ending at an altitude of FL330 or 10058.4 [m], provides a constraint-lapse having discrete steps, typical for transport aircraft (a 250 kt / 300 kt / M 0.78 climb profile).
Through the referenceEndconditionUID “altClimb”, a link to the altitude endCondition of the segment at the basis of this climb profile is provided.
Altitude from
Altitude to
calibratedAirspeed
machNumber
0.0 [m]
0.303 * 10058.4 = 3047.7 [m]
≤ 128.61 [m/s]
≤ 0.78 [-]
0.303 * 10058.4 = 3047.7 [m]
10058.4 [m]
≤ 154.33 [m/s]
≤ 0.78 [-]
The cruise phase is not fixed to a certain altitude and has no endCondition, since its range is determined by the segmentBlock information.
The descent phase makes sure the vehicle lands at an altitude of 0 [m].
In this case, since the values are not explicitly provided, it is up to the mission simulation software to determine, when the cruise phase ends and the descent phase starts.
climb
climb with: speed @ MFCS (set to machNumber le 0.78 [-]), altitude @ FL330
climb
10058.4
altitude
0.0;0.303
discrete
128.61;154.33
0.78;0.78
velocity
cruise
cruise with: speed @ optimum cruise speed, altitude @ optimum cruise altitude
cruise
descent to MSL
descent to MSL altitude
descent
0
]]>
Two more segmentBlocks make up the mission.
The “reserves” segmentBlock provides information for the cruise to alternate airport and loitering phase and the corresponding burnt fuel is considered reserveFuel.
The mission ends with a landing and taxiIn phase within the “endPhase” segmentBlock, of which the burnt fuel is considered additionalFuel.
The following then holds: blockFuel = designFuel + additionalFuel.
UID of the runway
Offset from runway threshold in cartesian coordinates in the runway coordinate system
Setting default and specific performance maps to be used for a model
Default performance map which is used if no other performance map
is assigned through the specificPerformanceMap node
List of specific performance maps used on dedicated mission segments or pointPerformance requirements
Specific performance settings for the segmentBlock (e.g.: a cruise Mach number)
Segment blocks
A list of segment blocks. A segment block specifies conditions for a predefined combination of segments (e.g.: setting the total range for a block of segments consisting of a takeOff, climb, cruise, descent and landing segment).
Segment block
A segment block specifies conditions for a predefined combination of segments (e.g.: setting the total range for a block of segments consisting of a takeOff, climb, cruise, descent and landing segment).
Name
Description
Segment direction. Either 'outbound' or 'inbound'. Only needed for radiusOfAction kind of missions.
List of segment uID's making up the segmentBlock. These should be ordered, such that the segment connections are correct.
Specifies to which type of mass the segment fuel mass
should be added (blockFuel = designFuel + additionalFuel; Total fuel requirement
= blockFuel + reserveFuel; designFuel = the fuel of the segmentBlock is part of the design mission)
Number of repetitions of this segment block, e.g. to perform repeated holding patterns
End condition
Specifies the end conditions for a segment or segment block (e.g.: an altitude or velocity). If a phase has no endCondition, it will base its endCondition on the segmentBlock settings (e.g.: it is the cruise segment, retrieving its total length based on the length of the segmentBlock minus all other segment lengths available within the segmentBlock).
Calibrated airspeed at the end of the segment [m/s]
Mach number at the end of the segment
Position at the end of the segment in xyz coordinates
Position at the end of the segment in geo coordinates
Reference to the runway on which the segment ends
massFraction ending the segment [-]
massFraction of remaining fuel ending the segment [-]
Absolute mass of remaining fuel ending the segment [kg]
Consumed fuel ending the segment [kg]
Power fraction of remaining at the end of the segment
Absolute power left ending the segment [W]
Consumed power ending the segment [W]
Flight heading at the end of the segment in compassAngle with reference to true North [deg]
Total change of heading angle during segment (a full turn is 360 degrees) [deg]
Flown distance ending the segment
Duration of the segment [hh:mm:ss]
UTC time at end of segment [hh:mm:ss]
Specific excess power at the end of the segment
Rate of climb ending the segment [m/s]
Achieved flightPathAngle ending the segment [deg]
List of stores released in the segment. The corresponding weightAndBalance vector for retrieving the new state as well as a potential change in aerodynamicPerformanceMap (if external stores are released) should be reflected within the configuration node at model level.
Mission segments
A collection of mission segments which can be reused to define missions.
Segment
Definition of a mission segment which can be used to define missions.
Name
Description
Type of the mission segment (takeOff, clime, cruse, ...)
Indication whether the distance flown during the segment is to be taken into account in the segmentBlock's distance calculation.
Environmental conditions. If the environmentalCondition is not provided at segment level, the conditions of the
previous segment are inherited (this inheritance can continue until the startCondition, where the initial
environmentalConditions are provided).
Fuel mass
Start conditions
Conditions which define the start of a mission
Calibrated airspeed at the start of the mission [m/s]
Mach number at the start of the mission
Global coordinate at the start of the mission in xyz coordinates
Global coordinate at the start of the mission in geographic coordinates (longitude, latitude, altitude)
UID of the runway at which the
mission starts
Flight heading at the start of the mission, in compassAngle with reference to true North
UTC time at start of mission
UID of the runway
Offset from runway threshold in the runway coordinate system
Missions
A list of missions.
Mission
Contains a list of segmentBlock uID's forming the mission along with additional mission information.
Name
Description
List of segmentBlock uID's forming the mission. Segments must first be grouped in segmentBlocks to be assigned to a mission.
mLandingGearsType
Landing Gears mass description
mLandingGearSupportsType
mLandingGearType
Landing Gear mass description
mLavatoriesType
mLiningsType
Mass
Manufacturer empty mass description
mMillitarySystemsType
Military systems mass description
mMoveableLeadingEdgesType
mMoveableLeadingEdgeType
mMoveablesType
mMoveableTrailingEdgeType
mNavigationType
Navigation mass description
Monetary values
Mass
Operator items mass description
mOverheadBinsType
mPartStowDoorsType
mPassengersType
mPassengerType
Passengers masses
Passanger masses Description
Passanger mass Description
Payload mass
Payload mass description
Pintle struts
Pintle struts mass description
Mass
Power units mass description
mPylonAttachmentsType
mPylonsType
Pylons mass description
Removable crew rests
Removable crew rest
mRibsType
mRibType
mSeatsType
mShellsType
mShellType
Side Struts
Side struts mass description
mSkinPanelsType
mSkinsType
mSparCellsType
mSparSkinsType
mSparsType
mSparType
mSpecialStructuresType
mSpoilersType
mStringersType
Mass
Structure mass description
Mass
Systems mass description
Toilet fluids
Toilet fluid
mTrailingEdgeDevicesType
mTrailingEdgeDeviceType
mULDContentsType
mULDContentType
UnusableFuels
Unusable fuel
mVacuumWasteSystemsType
mWallsType
mWasteWaterSystemsType
Water reservoirs
Water reservoir
Wheels
Wheels mass description
mWindowsType
mWingBoxType
mWingsStructureType
Wings structure mass description
mWingStructureType
Wing structure mass description
Center cowl
The centerCowl is defined by the rotation of a given curve profile (referenced via curveUID) around the x-axis.
Offset of the rotation curve in x-direction
UID of the curve profile (vehicles/profiles/curveProfiles/..)
Nacelle cowl
Describes the cowl geometry for nacelles
using sections positioned around the
rotational center of the engine.
Guide curves
Guide curve
The following figure shows the basic setup of the guide curves.
They always start at a given ζ-position (fromZeta) on the profile of the specified start section (startSectionUID) and end at the ζ-position (toZeta) on the profile of the subsequent section.
The relative coordinates of the guide curves are specified in cpacs/vehicles/profiles/guideCurves and referenced via its uID.
Note: Guide curves and profiles must result in a valid curve network.
The guide curve points are interpreted as (Δr and Δx) offsets from a cubic polynomial.
This polynomial serves as a baseline for guide curves between segments located on different radial positions with smooth transitions:
Note: Currently, the nacelles do not have an explicit guide curve type but employ the standard guide curve definition, which is used in wings and profiles.
Therefore, the parameters have a different meaning:
Standard guide curve parameter
Nacelle guide curve equivalent
Description
rX
φ
Independent variable normalized to
[0,1]
rY
Δx
Orthogonal offset (translation in x-direction)
rZ
Δr
Radial offset
Name
Description
UID of the guide curve profile
UID of the start section
Curve coordinate of the referenced section profile at which the guide curve shall start.
Valid values are in the interval -1,..,1.
Curve coordinate of the profile following the referenced section profile.
It defines where the guide curve ends.
Valid values are in the interval -1,..,1.
nacelleProfilesType
Nacelle profiles type, containing nacelle profile geometries.
See profileGeometryType for further documentation
Sections
Section
An engine nacelle is defined by sections, where at least one and up to an infinite number of sections can be specified.
Lofting of the nacelle surface along the sections is done in cylindrical coordinates.
The coordinate origin refers to the center of the fan, i.e. the sections and their profiles are typically shifted in negative x-direction.
Note: In the current CPACS release, transformations are still labeled as Cartesian coordinates.
It is current work in progress to explicitly introduce cylindrical coordinates.
Until this is implemented in a future CPACS release, the implicit conventions listed below apply:
Translation component
Cylindrical coordinate equivalent
Description
x
ϑ
Rotation angle around x
y
h
Horizontal translation
z
r
Radial translation
The following example illustrates the setup of a nacelle with 4 sections.
These are rotated by 0, 120, 180 and 240 degrees around the x-axis (given by translation/x).
To illustrate the possible transformations, the profile of the upper section is shifted slightly further in the negative x-direction (translation/y), while the lower section has a smaller radial distance from the rotation axis (translation/z).
In addition, the sections are scaled differently (transformation/scaling; not shown in the example figures) in order to create a straight trailing edge and to realize a flattened profile near the ground.
The following example also shows the profile cut-outs due to the radially symmetric inner region of the nacelle defined by therotationCurve.
For detailed information, please refer to the documentation of the rotationCurve element.
The first section is not rotated (x=ϑ=0), but shifted vertically in negative direction (y=h=-0.257).
The radial distance is given by z=r=0.365:
Upper section
1.055
1
1
0.0
-0.257
0.365
fanCowlUpperSectionProfile
]]>
The second section is rotated around the x-axis (x=ϑ=120) as well as scaled by a factor of 1.1 in its profile height:
Inboard section
1
1
1.1
120.0
-0.2
0.365
fanCowlUpperSectionProfile
]]>
The third section is rotated around the x-axis by 180° and scaled by a factor of 0.8 in its profile height:
Lower section
1
1
0.8
180.0
-0.2
0.33
fanCowlUpperSectionProfile
]]>
Name
Description
UID of the profile
Noise
FAR approach noise level
FAR sideline noise level
FAR take-off noise level
Nose landing gears
List of nose gears
Operating empty mass
Operating empty mass description
operationalCasesType
operationalCaseType
Operation Limit Increments
Changes of the deltas of operation limit angles with respect to the corresponding increment aeroPerformanceMaps.
Values are specified as an array with same indices like the corresponding increment map.
Minimum delta angle of attack [deg]
Maximum delta angle of attack [deg]
Orthotropic material properties for 2D materials
Defines the material properties for an orthotropic material in the plane stress state (i.e., shell). The strain-stress relationship is defined as:
Inverting the strain-stress relation and introducing thermal expansion yields:
with:
The terminology refers to the following literature:
[1] R. M. Jones, Mechanics Of Composite Materials, 2 New edition. Philadelphia, PA: Taylor and Francis Inc, 1998.
Young's modulus in material direction 1 [N/m^2]
Young's modulus in material direction 2 [N/m^2]
Shear modulus in material in 2-3 plane [N/m^2]
Shear modulus in material in 3-1 plane [N/m^2]
Shear modulus in material in 1-2 plane [N/m^2]
Poisson's ratio
Thermal expansion coefficient in material direction
1 [1/K]
Thermal expansion coefficient in material direction
2 [1/K]
Thermal conductivity of the material in material direction 1 [W/(m*K)]
Thermal conductivity of the material in material direction 2 [W/(m*K)]
Allowable stress for tension in material direction 1
[N/m^2]
Allowable stress for compression in material
direction 1 [N/m^2]
Allowable stress for tension in material direction 2
[N/m^2]
Allowable stress for compression in material
direction 2 [N/m^2]
Allowable stress for shear [N/m^2]
Allowable strain for tension in material direction 1
Allowable strain for compression in material
direction 1
Allowable strain for tension in material direction 2
Allowable strain for compression in material
direction 2
Allowable strain for shear
Orthotropic material properties for 3D materials
Defines the material properties for an elastic orthotropic material in three spatial directions (i.e., solid). The strain-stress relationship is defined as:
Note that nuij is related to nuji by:
The terminology refers to the following literature:
[1] R. M. Jones, Mechanics Of Composite Materials, 2 New edition. Philadelphia, PA: Taylor and Francis Inc, 1998.
Young's modulus in material direction 1 [N/m^2]
Young's modulus in material direction 2 [N/m^2]
Young's modulus in material direction 3 [N/m^2]
Shear modulus in the 2-3 plane [N/m^2]
Shear modulus in the 3-1 plane [N/m^2]
Shear modulus in the 1-2 plane [N/m^2]
Poisson's ratio in in 2-3 plane
Poisson's ratio in in 3-1 plane
Poisson's ratio in in 1-2 plane
Thermal expansion coefficient in material direction
1 [1/K]
Thermal expansion coefficient in material direction
2 [1/K]
Thermal expansion coefficient in material direction
3 [1/K]
Thermal conductivity of the material which couples heat flux in material direction 2 with temperature gradient in material direction 3 [W/(m*K)]
Thermal conductivity of the material which couples heat flux in material direction 3 with temperature gradient in material direction 1 [W/(m*K)]
Thermal conductivity of the material which couples heat flux in material direction 1 with temperature gradient in material direction 2 [W/(m*K)]
Allowable stress for tension in material direction 1
[N/m^2]
Allowable stress for compression in material
direction 1 [N/m^2]
Allowable stress for tension in material direction 2
[N/m^2]
Allowable stress for compression in material
direction 2 [N/m^2]
Allowable stress for tension in material direction 3
[N/m^2]
Allowable stress for compression in material
direction 3 [N/m^2]
Allowable stress for shear in 2-3 plane [N/m^2]
Allowable stress for shear in 3-1 plane [N/m^2]
Allowable stress for shear in 1-2 plane [N/m^2]
Allowable strain for tension in material direction 1
Allowable strain for compression in material
direction 1
Allowable strain for tension in material direction 2
Allowable strain for compression in material
direction 2
Allowable strain for tension in material direction 3
Allowable strain for compression in material
direction 3
Allowable strain for shear in 1-3 plane
Allowable strain for shear in 1-3 plane
Allowable strain for shear in 1-2 plane
outerCutOutProfileType
Parallelepiped
The component coordinate system is located in the center of the cuboid.
This means that "length" extends in the x-direction, "width" in the y-direction and "height" in the z-direction, half in the positive and half in the negative direction.
Length [m]
Width [m]
Height [m]
Angle between b and c [deg]
Angle between a and c [deg]
Angle between a and b [deg]
Container for parameter definitions
Contains a of the design parameter definitions.
Parameter definition for design studies.
Contains a name for the design parameter to give semantic meaning to parameters used in design studies.
Name of parameter
paxCrossBeamsAssemblyType
PaxCrossBeamsAssembly type, containing pax crossBeam
assemblies
paxCrossBeamStrutsAssemblyType
PaxCrossBeamStrutsAssembly type, containing pax
crossBeam strut assemblies
paxDoorsAssemblyType
PaxDoorsAssembly type, containing pax door assemblies
payloadGlobalType
Selection of performance maps
Engine performance map selection
Aerodynamic performance map selection
Configurations which apply for this performance requirement
Default configuration uID
Performance requirements
performanceTargetsGlobalType
Multi-phase mass flow
Pressure
Temperature
Multi-phase mass flow
Pressure
Temperature
Pintle strut(s) (Assumption: one end of the strut will connect to the main strut and the other end will be given as endPoint)
Pintle strut (one or two pintle struts are supported)
Piston
Geometric description and material properties of the
landing gear piston. The figure below shows the condition of the
uncompressed piston, where the length of the exposed part is the
sum of the
maxSpringDeflection
and the
compressedExternalLength
:
Length of the piston
Maximum spring deflection of the piston (difference between minimum and maximum deflection)
Length of the piston that remains outside of the main strut in fully compressed state
Points on plasticity curve of material
(min. 1 point)
plasticityCurvePointType
Tangent modulus [N/m^2]
True stress [N/m^2]
plasticityCurvesType
Plastification curve incl. element elimination (isotropic
materials). The data may be used to describe the plastic behavior of isotropic
materials in non-linear analysis, such as crash simulations. The input is defined
according to the needs of Material 103 (single stress strain option) in the
PAM-CRASH explicit Finite Element code, but can also be used for equivalent material
laws in alternative simulation environment (see PAM-CRASH Solver Reference Manual.,
Material 103).
This type describes the plasticity curve of isotropic
materials
...
Plastification curve incl. element elimination
(isotropic materials)
Plastification curve incl. element elimination (isotropic
materials) The data may be used to describe the plastic behavior of
isotropic materials in non-linear analysis, such as crash
simulations. The input is defined according to the needs of Material
103 (single stress strain option) in the PAM-CRASH explicit Finite
Element code, but can also be used for equivalent material laws in
alternative simulation environment (see PAM-CRASH Solver Reference
Manual., Material 103)
Source: PAM-CRASH V2010 - Notes Manual
Name of the post failure definition
Description of the post failure
definition
Strain rate for following plastcity
curve [1/s]
plasticEliminationStrain [-]; Plastic
strain for element elimination during
the non-linear analysis
Point with global/local reference
PointAbsRel type, containing an xyz data triplet. Each
of the components is optional. The refType attribute defines,
whether coordinates are absolute in the global coordinate system
[absGlobal], absolute in the parent element's local coordinate
system [absLocal]. If the object does not have a
parent, only [absGlobal] is permitted.
X-Component
Y-Component
Z-Component
Absolute values in global coordinate system
Absolute values in local coordinate system (default)
Point with constraints
Point constraint type, containing an xyz data triplet.
X-Component
Y-Component
Z-Component
List of 3D points, kept in three relative coordinate
vecors (rX, rY, rZ)
This set of vectors contains an ordered list of points
for rX, rY, and rZ coordinates in the form of stringBased
Vectors. The x, y and z vector elements with the same index
specify a 3D point relative to a geometric segment.
Vector of rX coordinates. Relative
circumferential coordinate on wing, fuselage or nacelle profile
Vector of rY coordinates. Relative span
coordinate along a segment
Vector of rZ coordinates. Relative coordinate
normal to the linear strake (normalised with chordlength /
diameter c*)
List of points
PointList type, containing an ordered list of points
Data point
List of points in x,y
PointList type, containing an ordered list of points
Data points in x-y-space.
List of 2D points, kept in two coordinate vecors (x, y)
This set of vectors contains an ordered list of points
for x and y coordinates in the form of stringBased Vectors.
The x and y vector elements with the same index specify a 2D
point. The coordinates of the x vector of [0, 1].
Vector of x coordinates
Vector of y coordinates
List of 3D points, kept in three coordinate vecors (x,
y, z)
This set of vectors contains an ordered list of points
for x, y and z coordinates in the form of stringBased Vectors.
The x, y and z vector elements with the same index specify a 3D
point.
Vector of x coordinates
Vector of y coordinates
Vector of z coordinates
Constraints
Constraint settings for the point performance definition
Calibrated airspeed [m/s]
Mach number [-]
Climb angle [deg]
Rate of climb [m/s]
Rate of turn [deg/s]
Thrust setting for derated engine as fraction of max. thrust (e.g.: for powered descents, deceleration not at IDLE, manoevres)
Rate of velocity [m/s^2]
Duration [s]
Angle of attack [deg]
Constant altitude [m]
Point performance definitions
List of point performance definitions
pointPerformanceType
Specific performance settings for the point performance calculation (e.g.: a cruise Mach number)
Name
Description
Defines at which part of the mission
the point performance should be
considered - after indicated segment
of the mission as defined in
performanceCase
Defines at which part of the mission
the point performance should be
considered - at the defined
massFraction within the mission as
defined in performanceCase
(mCurrent/mTO)
Defines at which part of the mission
the point performance should be
considered - at the defined
fuelFraction within the mission as
defined in performanceCase
(mFuelCurrent/mFuelTO)
Indicates the type of point performance
Requirements
Requirement settings for the point performance definition
Sustained load factor to be achieved
Instantaneous load factor to be achieved
Specific excess power to be achieved [m/s]
Roll rate to be achieved [deg/s]
Roll acceleration to be achieved upon control onset [deg/s^2]
Roll acceleration to be achieved upon control stop [deg/s^2]
Point: x,y,z
Point type, containing an xyz data triplet.
X-Component
Y-Component
Z-Component
Point: x
Point type, containing a x data.
X-Component
Point: x,y
Point type, containing an xy data doublet.
X-Component
Y-Component
Point: x,y,z
Point type, containing an obligatory xyz data triplet.
X-Component
Y-Component
Z-Component
Point: x, z
Point type, containing an xz data doublet.
X-Component
Z-Component
Point: y
Point type, containing a y data.
Y-Component
Point: y, z
Point type, containing an yz data doublet.
Y-Component
Z-Component
Point: z
Point type, containing a z data.
Z-Component
Positive double values larger than 0
Positive integer values larger than 0
Vector with semicolon separated positive integer values
Any positive integer values separated by semicolons are permitted, e.g.:
<intVectorTest>0;1;2;3;4;5</intVectorTest>
<intVectorTest>1</intVectorTest>
<intVectorTest>0,1,2,3,4,5</intVectorTest>
<intVectorTest>0.;1.;2.</intVectorTest>
<intVectorTest>-1;0;1</intVectorTest>
Positionings of the wing.
Positionings type, containing all the positionings of
the wing sections.
Positioning of the wing section
The positionings describe an additional translation of
sections. Basically, the positioning is a vector having the
length 'length' and an orientation that is described by the
parameters 'sweepAngle' and 'dihedralAngle'. If the 'sweepAngle'
and the 'dihedralAngle' are set to zero (or left blank) the
positioning vector equals the positive y-axis of the coordinate
system (in case of a positive 'length').
If the parameter 'fromSectionUID' is set, the
positioning describes the translation between the 'from' towards
the 'to' section. If the parameter 'fromSectionUID' is left
blank the origin of the positioning vector is the origin of the
parent coordinate system.
The origin of the section coordinate system is the
position which is described by the positioning vector PLUS the
translation which is described in the section.
Please note: If the origin of the positioning vector is
defined by using another section, i.e. fromSection is defined,
the origin of this vector equals the end of the positioning
vector of the previous section. This means that the section
translation of the from-section has no influence on the
positioning of the to-section. Therefore the total translation,
which is described by positionings, is the sum of the current
positioning and all positionings that are defined 'before'.
An example for this is given at positioning 3 and 4 at
the picture below. Please note, that any other combination of
positionings would be possible.
Application of the sweepangle does not lead to a
rotation of the section. Application of the dihedral does not
lead to a rotation of the section.
Name of the positioning.
Description of the positioning.
Distance between inner and outer section
(length of the positioning vector).
Sweepangle between inner and outer section.
This angle equals a positive rotation of the positioning vector
around the z-axis of the wing coordinate system.
Dihedralangle between inner and outer section.
This angle equals a positive rotation of the positioning vector
around the x-axis of the wing coordinate system
Reference to starting section of the
positioning vector. If missing, the positioning is made from the
origin of the wing coordinate system.
Reference to ending section (section to be
positioned) of the positioning vector.
Specification of the power breakdown case
Altitude
Mach number
Calibrated air speed
True air speed
UID of global flight point at cpacs/vehicles/flightPoints/flightPoint
Configuration
Power breakdowns
Power flow
Name
Description
UID of the system architecture connection
Power flow
Power flow
pressureBulkheadAssemblyPositionType
PressureBulkheadAssemblyPosition type, containing a
pressure bulkhead assembly position
Frame to which bulkhead is attached to
UID of bulkhead element description
pressureBulkheadAssemblyType
PressureBulkheadAssembly type, containing pressure
bulkhead assemblies
pressureBulkheadsType
PressureBulkheads type, containing pressure bulkheads
pressureBulkheadType
PressureBulkhead type, containing data of a pressure
bulkhead
Name of the pressure bulkhead structural
element
Description of the pressure bulkhead
structural element
UID of structural sheet element used for the
bulkhead
Choice between flat and curved bulkhead types
additional data for flat (forward) pressure
bulkhead
Number of vertical reinforcements on flat
bulhhead
UID of structural elements used as vertical
reinforcements
Number of horizontal reinforcements on flat
bulhhead
UID of structural elements used as
horizontal reinforcements
additional data for curved (rear) pressure
bulkhead
Radius of bulkhead calotte in the plane of
the adjacent frame
maximum flection of the pressure bulkhaed
calotte
Number of radial reinforcements (equally
distributed) on curved bulhhead
UID of structural elements used as radial
reinforcements on curved bulkheads
structuralElementType
profileBasedStructuralElements type, containing a list
of profile based structural elements
Structural elements based on profiles
Short description
The ProfileBasedStructuralElement type containins the data of a structural element, that are based on 2-dimensional profiles.
There are three approaches to model profile based structural elements:
by specifying global beam properties
by referencing a structuralProfile2D element
by choosing one of the prescribed standard profiles
1. Global beam properties
In the section globalBeamProperties the properties of the structural profile in an equivalent beam representation are defined.
2. Structural 2D profile
The structuralProfileUID element refers to the uID of the structuralProfile2D element.
As described in the corresponding documentation, this profile is defined by several points in the x-y-space.
Two points always form a sheet.
The properties of each sheet are defined in the sheetProperties element.
The orthotropy direction of composite materials equals the sheets' x-axis.
The orthotropy direction angle equals a positive rotation around the sheets' z-axis as indicated in the picture below (part 3), which shows an example of a wing stringer.:
3. Standard structural 2D profile
Instead of referencing a structuralProfile2D element, it is also possible to select a predefined standard profile.
These profiles are listed in the figure below.
Under sheetProperties, only the standardProfileSheetID (equals S1, S2, ...) must now be specified along with a corresponding length.
Name of the profile based structural element
Description of the profile based structural
element
Choice between global beam properties and sheet properties
Choice between general profile element
description (referencing a structuralProfile) and predefined
standard profiles
Definition based on structuralProfile
definition
Reference to the structural profile profile
uID
Reference point in structural profile
definition for structural element definition
Standard Profile Type, see picture below for
further information.
profileGeometry2DType
A profile is defined by a profile name, an optional
description and a 2-dimensional pointlist with both
coordinates mandatory. All point coordinates are transferred
to the global coordinate system depending on the context they
are used in. The points have to be ordered in a mathematical
positive sense. The x-coordinates of the profile has to be
normalized between 0 and 1. First and last point
may, but need not to, be identical. Hence, it is possible to
include "open" profiles. However, the trailing edge position of
the upper and lower point need to be identical. No crooked
trailing edges are possible.
Example 1: For a conventional nacelle profile, the airfoil
coordinates are defined in x and y. The points have to be ordered
from the trailing edge along the lower side to the leading
edge and then along the upper side back to the trailing edge.
When used for a nacelle the profile axis align
with the global axes as follows:
+x_profile -> +x_global;
+y-profile -> -z_global
Example 2: For a fuselage, the coordinates are
also given in x and z with x as the normalized fuselage height.
Starting point of the profile should be the lowest point
(typically in the symmetry plane), then upwards on the positive x-side up to the highest
point (again, typically in the symmetry plane). Depending on,
whether the fuselage shall be specified with symmetry condition
or not, the profile either ends there, or continues on the
negative x-side back down to the lowest point.
Alternatively, it is possible to specify the
coordinates of a profile via the CST (class function /shape
function transformation technique) notation. Please see the
cst2DType for further information.
A profile can be symmetric. In that case the profile
is interpreted as being not closed and will be closed by
mirroring it on the symmetry plane.
Name of profile
Description of profile
profileGeometryType
A profile is defined by a profile name, an optional
description and a 3-dimensional pointlist with all three
coordinates mandatory. For typical profiles, one of the
coordinate vectors contains only "0" entries. All point
coordinates are transferred to the global coordinate system. The
points have to be ordered in a mathematical positive sense.
Normalized coordinates are not required. First and last point
may, but need not to, be identical. Hence, it is possible to
include "open" profiles. However, the trailing edge position of
the upper and lower point need to be identical. No crooked
trailing edges are possible.
Example 1: For a conventional wing, the airfoil
coordinates are defined in x and z with all the y-coordinates
set to "0". The points have to be ordered from the trailing edge
along the lower side to the leading edge and then along the
upper side back to the trailing edge.
Example 2: For a fuselage, the coordinates are
typically given in y and z with x set to "0". Starting point of
the profile should be the lowest point (typically in the symmetry
plane), then upwards on the positive y-side up to the highest
point (again, typically in the symmetry plane). Depending on,
whether the fuselage shall be specified with symmetry condition
or not, the profile either ends there, or continues on the
negative y-side back down to the lowest point.
Alternatively, it is possible to specify the
coordinates of a profile via the CST (class function /shape
function transformation technique) notation. Please see the
cst2DType for further information.
A profile can be symmetric. In that case the profile
is interpreted as being not closed and will be closed by
mirroring it on the symmetry plane.
Name of profile
Description of profile
Profiles
Profiles type, containing profile geometries
Attachments of the pylon to the parent.
Attachment of the pylon to the parent.
Material properties of the attachment.
Link to the structural profile of the
attachment.
UID of the attachment.
Structural properties of the pylon box (ribs, upper,
lower and side panels).
UID of the pylon box.
Definition of pylon pins.
Definition of one pylon pin.
First element (parentAttachmentUID, engineUID
or uID of a pylon structure.
Second element (parentAttachmentUID, engineUID
or uID of a pylon structure.
Position of the pylon pin related to the pylon
coordinate system.
Blocked DOFs. Refers to the rotated
coordinate system that is defined in 'orientation'.
UID of the pin.
Structural properties of all tibs of the engine pylon
box.
Definition of a rib set.
RibDefinitionType, containing the definition for ribs.
Ribs are defined in sets of one or more ribs. The positions of
the rib, as well as the orientation of the ribs are defined in
'ribPositioning'. The cross section properties, as e.g.
materials, are defined in 'ribCrossSection'.
Name of the rib set.
Description of the rib set.
pylonRibsPositioningType
Within the ribsPositioning type the position and the
orientation of the ribs of the rib set are defined.
The forward and the rear beginning of the rib set is
defined using relDepthStart and relDepthEnd. The orientation of
the ribs is defined in ribRotaton. The number of ribs of the
current rib set is either defined by ribNumber or by spacing.
relDepthStart defines the forward location of
the beginning of the rib set. 0 equals the forward end of the
pylon box, while 1 equals the rear end of the pylon box.
relDepthEnd defines the rear end. 0 equals the
forward end of the pylon box, while 1 equals the rear end of the
pylon box.
Ribs can be rotated in the side view. The
defaults to 90°, which equals an orientation along the pylons
z-axis. The angle is measured around the positive y-direction
of the pylon.
The spacing of the ribs defines the distance
between two ribs, measured along the pylons x-axis. First rib
is placed at relDepthStart.
RibNumber defines the number of ribs in this
ribSet. First rib is at relDepthStart along the pylons x-axis,
last rib is at relDepthEnd. The spacing is constant.
RibCrossingBehaviour can either be "cross" or
"end". If it is end then ribs will end it they intersect
another rib. It it is cross ribs are placed uncut.
Structural properties of pylon shackles (for pylon to
parent attachment), if existing.
Structural properties of a pylon shackle.
Material properties of the shackle.
Link to the structural profile of the shackle.
UID of the shackle.
Structural properties of the pylon shells.
UID of the structural profile.
Material settings.
UID of the structure.
Definition of the load carrying structure of the engine
pylon.
Structural properties of struts (drag struts, upper
links and tangent links), if existing.
radiativeForcingType
Rectangle
The width of the profile is always 1, since scaling is performed after referencing it (e.g., in the fuselage).
The resulting profile is defined by the following equation:
with c = cornerRadius and r = heightToWidthRatio.
Example: Rectangle with cornerRadius=0.125 and heightToWidthRatio=0.5
Corner radius
Height-to-width ratio
recurringCostType
Reference values
Reference type, containing the reference values of the
aircraft model
Reference area (typically planform area)
Reference length (typically Mean Aerodynamic
Chord MAC). In CPACS, only one reference length exists (and is
used, e.g. for all three moment coefficients. Coordinates given
relative to MAC shall always use this length as MAC.
Moment reference point (in global coordinate
system). The x-coordinate is typically chosen same as of the
leading edge of the wing in the spanwise section having a
chordlength identical to MAC. Coordinates given as %MAC shall
always use this x-coordinate and length (e.g. 0%MAC = x, 100%MAC
= x + length). The y coordinate is typically 0. The z coordinate
is often chosen either as 0., or as z of fueselage nose or as z
of middle of center fuselage part.
Released stores
Released store
uID of the released store(s).
Quantity of released stores
Remaining contributions to aerodynamic coefficients
This node lists the remaining contributions which were not specified so that the sum of the coefficients are equal to the total coefficients.
Remaining contribution to aerodynamic coefficients
This node lists a remaining contribution which was not specified so that the sum of the coefficients are equal to the total coefficients.
Name
Description
Type (numerical/unspecified): "numerical", for example, describes rounding errors to clearly
separate them from other effects currently labelled as "unspecified".
The latter usually summarizes physical effects such as viscosity and should be further described via "description".
The approach is currently being tested in practice in order to derive a robust definition of categories in the future.
Requirement classification based on the MoSCoW method (must, should, could or wont)
requirementType
RibIdentificationType, defining one rib.
UID of the rib definition set.
Number of the rib of the rib definition set.
Definition of the rib rotation
The rotation around z describes the rotation around the
wings midplane normal axis. The defaults to 90°. The reference
for the 'zero-angle' of the z-rotation is defined in
ribRotationReference.
RotationReference defines the reference for
the z-rotation it is either sparUID, „LeadingEdge“,
„TrailingEdge“, "globalX", "globalY" or "globalZ".
If it is not defined the rotation reference is
the eta-axis (=leading edge, that is projected on the wings
y-z-plane). A z-rotation angle of 90 degrees means, that the rib
is perpendicular on the ribRotationReference (e.g. spar, leading
edge...). The rib itself is always straight, and the rotation
is defined with respect of the intersection point of the rib
with the ribRotationReference.
The rotation around z describes the rotation
around the wings midplane normal axis. The defaults to 90°. The
reference for the 'zero-angle' of the z-rotation is defined in
ribRotationReference.
rivetJointAreaAssemblyPositionType
RivetJointAreaAssemblyPosition type, containing a rivet
joint area assembly position
rivetJointAreasAssemblyType
RivetJointAreasAssembly type, containing rivet joint
area assemblies
rivetsType
Rivets type, containing rivets
rivetType
Rivet type, containing a rivet
Name of the rivet type
Description of the rivet type
Tensile Strength of the rivet type
Shear Strength of the rivet type
Rotation curve
The figure below shows an example of a rotation curve.
Together with the corresponding XML code, the definition is explained in more detail.
First, the reference system is defined via referenceSectionUID, for which in this example the section with uID="engine_nacelle_fanCowl_section1" is referenced.
This in turn contains a transformation (not shown here), for example a translation by z=0.4 and a scaling, where the x-direction is stretched by a factor of two.
The rotation curve is now described in this reference system.
It is predefined in the profile library and referenced via a its uID.
Note that the curve is defined in the range x=[0,..,1] in order to be reasonably transformed by the reference system.
Next, the blending from the rotated profile of the nacelle segment to the rotation curve is defined.
The corresponding start and end points are given in curve coordinates zeta of the corresponding profiles.
Note that the lower part of the segment profile counts from zeta=[-1,..,0] and the upper part counts from zeta=[0,..,1].
In between, the blending is linear.
engine_nacelle_fanCowl_section1
fanCowl_upperSection
-0.6
-0.5
-0.2s
-0.1
]]>
Fan cowl rotation curve profile
0;0.5;1
-0.1;-0.2;-0.05
]]>
UID of the section which serves as reference
Start zeta [-1,..,1]; relative curve coordante along the rotation curve from which it will be inserted in the nacelle.
End zeta [-1,..,1]; relative curve coordante along the rotation curve up to which it will be inserted in the nacelle.
Start zeta for blending [-1..1]; relative curve coordinate along the nacelle profile at which blending from the nacelle profile to the rotation curve will begin.
End zeta for blending; relative curve coordinate along the nacelle profile at which blending from the rotation curve to the nacelle profile will end.
UID of the rotation curve profile; the profile should be defined in x=[0..1] to be transformed by the section which is referenced by referenceSectionUID.
rotorAirfoilsType
RotorAirfoils type, containing rotor airfoil
geometries. See profileGeometryType for further documentation
rotorBladeAttachmentsType
RotorBladeAttachments type, containing all hinges and
blade UIDs attached to the current rotor hub.
rotorBladeAttachmentType
RotorBladeAttachment type, defining the elements used
to attach one or more rotor blades to the rotor head.
Name of the blade attachment.
Description of the blade attachment.
The azimuthAngles element is used to specify
a list of discrete azimuth angles (in deg) at which instances
of attached blades are to be created. The number of blades will
equal to the number of elements of the vector. E.g.
<azimuthAngles>0;90;180;270</azimuthAngles> for a
four blade rotor with equal equiangularly distributed blades.
The transformation of the respective rotor blade corresponds to
a rotation by azimuthAngle around the z axis of the rotor
coordinate system in mathematically positive sense of rotation.
If only the number of blades is specified,
the attached blades will be distributed equiangularly and the
first blade will be attached at azimuth angle 0. (Formula:
azimuthAngle[i] = i*360deg/numberOfBlades,
i=0..numberOfBlades-1)
Definition of all hinges used to attach the
rotor blade.
UID of the rotorBlade which should be attached
to the rotor hub.
rotorBladesType
RotorBlades type, containing all the rotor blade
gometry definitions of an rotorcraft model.
Rotor blade geometries are defined using the same data
structure as wings (wingType). But in order to be compatible
with the other rotor blade related types (e.g. rotorType,
rotorHubType, rotorHubHingeType) there are some additional
conventions/requirements regarding the definition and
orientation of rotorBlade geometries:
Rotor blades should be positioned relative to the
global z-axis the way they will be positioned to the rotor
shaft (when blade azimuth=0deg).
The global x-axis should be used as radial axis
(usually the quarter chord line of the rotor blade coincides to
a great extent with the x-axis of the rotor blade coordinate
system).
All sections should be positioned in the positive
x halfspace.
Segments should connect sections with ascending x
coordinates.
Airfoils defined in the rotorAirfoils node should
be used instead airfoils from the wingAirfoils node.
Rotor blade geometries are defined using the
same data structure as wings (wingType). But in order to be
compatible with the other rotor blade related types (e.g.
rotorType, rotorHubType, rotorHubHingeType) there are some
additional conventions/requirements regarding the definition and
orientation of rotorBlade geometries: see remarks.
rotorcraftAnalysesType, results from several analysis
modules connected to CPACS
RotorcraftAnalyses type, containing detailed analysis
data of the rotorcraft
Within this element results from analysis modules are
stored that rely to the overall definition of the rotorcraft.
These include e.g. aerodynamic data or loadCases
For further documentation please refer to the
respective elements.
rotorcraftGlobalType
RotorcraftGlobalType type, containing global data of
the rotorcraft
Number of passenger seats
Cargo transport capacity [kg]
Cruise Mach Number
Configuration of the rotorcraft:
standard(single main rotor, single tail rotor) / tandem /
coaxial/intermeshing / sideBySide/tiltRotor/tiltWing
massBreakdownType
1. General
The massBreakeDown is subdivided in designMasses, fuel,
payload and mOME (operating empty mass).
designMass
The design mass is a description from TLARs and can
be understand as design criteria.
fuel and payload
The fuel and payload mass are the maximum masses
which can be achieved. Full fuel tanks, all passengers on
board and full cargo holding.
mOEM
The operation empty mass structure is based on the Airbus Mass
Standard brake down [AIRBUS MASS STANDARD 2008]. The
operator’s mass empty (OME) is defined by the sum of the
following component masses:
operator’s items
manufacturer’s mass empty (MME)
2. massDescription
Each sub component has the following
massDescription
which include a:
Name
Description
parentUID
Mass value
Mass location
Mass orientation
Mass Inertia.
That massdescription can be found at the designMasses direct under each item.
At the fuel, payload and mOME under massDescription in each item and sub item.
For the clean up the mOME there is consisting a script witch is programmed in Matlab but also as standalone vision available.
Setting for that tool can be done under toolspesifics/cmu.
Mass
Manufacturer empty mass description
Mass
Group mass of hierarchy level 1
Mass
Group mass of hierarchy level 2
Operating empty mass
Operating empty mass description
rotorcraftModelType
RotorCraftModel type, containing a complete rotorcraft
model (Geometry and all specific data). The rotorcraftModelType
is basically a copy of the aircraftModelType with the following
additional elements: rotors, rotorBlades, driveSystems.
Furthermore the following elements have been adapted for
rotorcraft: global and analyses (aeroPerformance and
massBreakdown).
Name of rotorcraft model
Description of rotorcraft model
Rotorcraft
Rotorcraft type, containing all the rotorcraft models.
Most of the extensions used in the rotorcraft type have
been defined as part of the work in the DLR project RIDE
(Rotorcraft Integrated Design and Evaluation, 2009-2012).
Therefore some of the definitions and conventions are tightly
coupled to the RIDE toolchain and tools. Further generalization
and assimilation of these parts to the definitions for fixed-wing
aircraft is planned for the near future.
Rotor blade elements
RotorBlades type, containing all the rotor blade
gometry definitions of an rotorcraft model.
Rotor blade geometries are defined using the same data
structure as wings (wingType). But in order to be compatible
with the other rotor blade related types (e.g. rotorType,
rotorHubType, rotorHubHingeType) there are some additional
conventions/requirements regarding the definition and
orientation of rotorBlade geometries:
Rotor blades should be positioned relative to the
global z-axis the way they will be positioned to the rotor
shaft (when blade azimuth=0deg).
The global x-axis should be used as radial axis
(usually the quarter chord line of the rotor blade coincides to
a great extent with the x-axis of the rotor blade coordinate
system).
All sections should be positioned in the positive
x halfspace.
Segments should connect sections with ascending x
coordinates.
Airfoils defined in the rotorAirfoils node should
be used instead airfoils from the wingAirfoils node.
Rotor blade geometries are defined using the
same data structure as wings (wingType). But in order to be
compatible with the other rotor blade related types (e.g.
rotorType, rotorHubType, rotorHubHingeType) there are some
additional conventions/requirements regarding the definition and
orientation of rotorBlade geometries: see remarks.
Rotor blade
Name of the wing.
Description of the wing.
Rotor
Rotor type, containing a rotor (main rotor, tail rotor,
fenestron, propeller,...) of an rotorcraft model.
Rotor type, containing a rotor (e.g. main rotor, tail
rotor, fenestron, propeller,...) definition of a rotorcraft
model.
The position and attitude of the rotor is defined
using the transformation element. The following image shows the
CPACS conventions for the orientation of rotors and rotor axis
systems:
The origin coincides with the center of rotation.
The z-axis corresponds to the axis of rotation
and thus coincides with the rotor shaft centerline. It Points
in the main thrust direction of the rotor (usually upwards for
a main rotor, forwards for a propeller).
The x-axis points from nose to tail (usually
rearwards for main and tail rotors, upwards for a propeller).
The y-axis completes the right-handed orthogonal
coordinate system.
Rotor hub attributes, hinges and references to
attached rotor blades are defined in the rotorHub element.
Note that rotor blade geometries are only referenced and not defined in the child nodes of the rotor element.
Refer to the documentation of rotorBladesType (Empty#T/rotorBladesType) and wingType (Empty#T/wingType) for information on the definition of rotor blade geometries.
The following figure shows the transformations to be
applied to rotorBlade geometries to visualize them in the rotor
frames for a given state (each rotor: rotorAzimuth given, each
hinge: hingeDeflection given):
Name of the rotor.
Description of the rotor.
Nominal value of the angular rotation speed in
rotations per minute (rpm).
The rotorHub element contains the definition
of the rotor hub type and number and azimuth angles of the
attached blades and their hinges. The rotor hub position and
attitude coincides with the rotor axis system's origin and z
axis.
Rotor elements
rotorHubHingesType
RotorHubHinges type, defining hinges used to attach a
rotor blade to the rotor head.
Definition of a flap, lead-lag or pitch hinge.
rotorHubHinge type, containing a rotor hub hinge
(flap/leadLag/pitch).
RotorHubHinge type, containing a rotor hub hinge
(flap/leadLag/pitch) of a rotorcraft model.
Name of the hinge.
Description of the hinge.
Hinge type. Possible values: "flap", "pitch"
"leadLag". This is used to define the rotation axis of the hinge
(flap = y-axis in blade cs, pitch = x-axis in blade cs, lead-lag
= z-axis in blade cs).
The angle (in deg) at which the hinge is in
neutral position. This element is normally used to define
precone or prelag angles of the attached blade. Defaults to 0.
Static stiffness of the hinge in (N/m) for
linear hinges and (N.m/deg) for angular hinges. Default value:
+inf (statically rigid hinge)
Dynamic stiffness of the hinge in (N/m) for
linear hinges and (N.m/deg) for angular hinges. Default value:
+inf (statically rigid hinge)
Damping of the hinge in (N/(m/s)) for linear
hinges and (N.m/(deg/s)) for angular hinges. Default value: +inf
rotorHubType
RotorHub type, containing definitions for the rotor hub
and attached hinges and blades.
Name of the rotor hub.
Description of the rotor hub.
Rotor head type. Possible values: "semiRigid",
"rigid", "articulated", "hingeless"
Rotor blade attachments are used to define how
many rotor blades are attached at which azimuth positions of the
rotor hub and the used hinges.
rotorsType
Rotors type, containing all the rotors (mainRotors,
tailRotors, fenestrons, propellers, ...) of an rotorcraft model.
Rotor type, containing a rotor (main rotor, tail rotor,
fenestron, propeller,...) of an rotorcraft model.
Rotor type, containing a rotor (e.g. main rotor, tail
rotor, fenestron, propeller,...) definition of a rotorcraft
model.
The position and attitude of the rotor is defined
using the transformation element. The following image shows the
CPACS conventions for the orientation of rotors and rotor axis
systems:
The origin coincides with the center of rotation.
The z-axis corresponds to the axis of rotation
and thus coincides with the rotor shaft centerline. It Points
in the main thrust direction of the rotor (usually upwards for
a main rotor, forwards for a propeller).
The x-axis points from nose to tail (usually
rearwards for main and tail rotors, upwards for a propeller).
The y-axis completes the right-handed orthogonal
coordinate system.
Rotor hub attributes, hinges and references to
attached rotor blades are defined in the rotorHub element.
Note that rotor blade geometries are only referenced and not defined in the child nodes of the rotor element.
Refer to the documentation of rotorBladesType (Empty#T/rotorBladesType) and wingType (Empty#T/wingType) for information on the definition of rotor blade geometries.
The following figure shows the transformations to be
applied to rotorBlade geometries to visualize them in the rotor
frames for a given state (each rotor: rotorAzimuth given, each
hinge: hingeDeflection given):
Name of the rotor.
Description of the rotor.
UID of the part to which the rotor is mounted
(if any). The parent of the rotor can e.g. be the fuselage. In
each rotorcraft model, there is exactly one part without a
parent part (The root of the connection hierarchy).
Rotor type. Possible values: "mainRotor"
(default), "tailRotor", "fenestron" or "propeller"..
Nominal value of the angular rotation speed in
rotations per minute (rpm).
Transformation (scaling, rotation,
translation). This element is used to define the position and
attitude of the rotor relative to the global or the parent
component's axis system. Note that an anisotropical scaling
transformation should not be applied to the rotor.
The rotorHub element contains the definition
of the rotor hub type and number and azimuth angles of the
attached blades and their hinges. The rotor hub position and
attitude coincides with the rotor axis system's origin and z
axis.
runwayILSType
RunwayILS type, containing ILS data of a runway
Position of the localizer antenna
Position of the glide slope antenna
Angle of the glide path
Runway start position
Description of the vehicle on the runway relative to the runway threshold.
X-position in cartesian coordinates in the runway coordinate system
Y-position in cartesian coordinates in the runway coordinate system
Z-position in cartesian coordinates in the runway coordinate system
Lengthwise distance along the runway centerline from the runway threshold
Lateral offset from the runway centerline. Positive values on the starboard side.
runwaysType
Runways type, containing data of the airport's runways
runwayType
Runway type, containing data of a runway
Name of runway
Description of runway
Position in degrees north
Position in degrees east
Threshold elevation
Runway heading
Takeoff run available
Landing distance available
Conditions of the runway
Seat elements
Seat element collection type
Seat element for use in the decks
Seat element
Seat element type, containing the base elements of the cabin
Number of seats
Seat modules
Seat module instance collection type.
Seat module
shaftLinkedComponentsType
ShaftLinkedComponents type, containing UIDs of engines,
transmissions and rotors linked by a shaft.
UID of a linked engine.
UID of a linked transmission shaft input.
UID of a linked transmission shaft output.
UID of a linked rotor.
shaftsType
Shafts type, containing all the shafts of a drive
system.
shaftType
Shaft type defining a shaft used as a link between
drive system components.
sheet3DType
sheetBasedStrcuturalElementsType
sheetBasedStrcuturalElementsType, containing sheet
based structural element definitions
sheetBasedStructuralElementType
sheetBasedStructuralElementType type, sheet definition
for use in fuselage/structure
Material definition of the skin segment
(Material, thickness, (lay-up))
sheetList3DType
List of sheets, connecting 2-dimensional profile
points.
SheetList type, containing a list of sheets. Each sheet
combines two points to one sheet.
sheetPointsType
sheetType
Sheet type, containing connection data of a sheet
Name of sheet within the profile definition
Description of sheet within the profile
definition
Point from which the sheet definition starts
start
Continuity definition for profile geometry
generation. 0= C0 (allows sharp edges, default), 1= C1 (defines
tangential continuity), 2= C2 (defines curvature continuity)
2=all
Definition of an orientation vector at P1
Point at which the sheet definition ends
Continuity definition for profile geometry
generation. 0= C0 (allows sharp edges, default), 1= C1 (defines
tangential continuity), 2= C2 (defines curvature continuity)
2=all
Definition of an orientation vector at P2
Side strut(s) (Assumption: one end of the strut will connect to the main strut and the other end will be given as endPoint)
Sidewall panel elements
Sidewall panel element collection type
Sidewall panel element for use in the decks
Sidewall panels
Sidewall panel instance collection type.
Sidewall panel
singleGenericMassType
Skid landing gears
List of skid gears
fuselageSkinSegmentType
FuselageSkinSegment type, containing material on skin
over circumference
fuselagePanelType
FuselagePanel type, panel of the fuselage between
stringers/ frames (new in V1.5)
UID of sheetBasedStructuralElement used for
the panel
UID of frame at start of the skin segment
UID of frame at end of the skin segment
UID of stringer at start of the skin segment
UID of stringer at end of the skin segment
skinType
Containing data defining the skin
Default UID of sheetBasedStructuralElement
used for the fuselage skin not covered by individual panels
Source / Target
UID of a component defined under aircraft(rotorcraft)/model
UID of a sub-component
External element (ambient | passengers), which is not explicitly defined in CPACS.
External elements indicate that this is an element relevant to modeling the system, but is not itself contained in the system.
Source / target system according to ATA chapter
UID of another systemArchitecture
SparCells of current spar.
sparCells are an optional Element. They are defined via
the etaCoordinates and define a region of special cross section
and material properties.
Spar cell of the spar.
Within spar cells a special area of the spar is
defined where different cross section and material properties
shall be defined.
The area of the spar is defined by using the
parameters 'fromEta' and 'toEta'. The definition of the caps,
webs and rotation is equivalent to the cross section definition
of the complete spar.
Beginning (= inner border) of the spar cell.
Ending (= outer border) of the spar cell.
Upper Cap
Lower Cap
Web 1
Web 2
The angle between the wing middle plane and
web 1 [deg]. Default is 90 degrees. Positive rotation is around the
spar axis heading along with the positive eta-axis.
Definition of the spar cross section.
Spar type, containing the cross section definition of
a spar. The spar middle point is defined by the intersection of
the wing middle plane and web1. This equals the coordinate
defined within the sparPosition.
Please find below a picture where all spar cross
section parameters as well as the orientation references for
the material definition can be found:
The angle between the wing middle plane and
web1. Default is 90 degrees. Positive rotation is around the
intersection axis of the spar and the wing middle plane. The
positive heading of this axis is inline with the positive
heading of the componentSegment eta-axis.
Spar definition points on the wing.
sparPositionType, a sparPostion defines a location
within the componentSegment where a spar in mounted. Eta and xsi
are relative to the componentSegment.
Please find below a picture for an example definition
of 3 spars in one wing, by using spar position points and spar
segments:
Spar position on the wing
sparPositionType, a sparPostion defines a location
within the componentSegment where a spar in mounted. Eta and xsi
are relative to the componentSegment.
Please find below a picture for an example definition
of 3 spars in one wing, by using spar position points and spar
segments:
As an alternative to the relative eta coordinate it is
possible to specify an elementUID so that the spar position is
relative to the outer geometry, e.g. kink, of the wing.
Defines a spar position on an existing rib using a relative xsi coordinate
to determine the chord wise position on that rib
Defines a spar position using relative eta/xsi coordinates
Defines a spar position via a point on a curve
sparPositionUIDs of the spar.
sparPositionType, a sparPostion defines a location
within the componentSegment where a spar in mounted. Those
positions are combined to spars by using a list of spar position
uIDs. The order of the sparPositionUIDs must be the same as the
order of the points on the real spar (from root to tip or from
tip to root).
Please note: orientation of a spar must be always
outbound or always inbound. A zigzag spar orientation where
e.g. the spar starts at the root, goes to the tip and goes back
to another point at the root is not allowed.
Please find below a picture for an example definition
of 3 spars in one wing, by using spar position points and spar
segments:
List of spar position uIDs.
Spar segments of the wing.
sparSegmentsType, containing multiple sparSegment
(=spars) of the wing.
SparSegments (=spars) of the wing.
SparSegmentType, each spar is defined by multiple
sparPositions that are referenced via their uID. The spar cross
section is defined in 'sparCrossSection'.
Name of the spar segment (=spar).
Description of the spar segment (spar).
Species
Share
Species type
List of segment uIDs to which the configuration is to be applied
Specification of a segment uID and index of the parameter lapses
UID of the segment for which the specific configuration holds.
Vector with semicolon separated indices of the parts of the respective segment within the mission definition for which the specific configuration setting holds. Example: scheduling configurations for a climb or descent segment (different settings of moveables and gears) on altitudes/velocities
Specific configuration uIDs
Connection between segments, pointPerformances and a configurationUID
Configuration uID
List of pointPerformanceUIDs
Specific heat map, containing the specific heat capacity of a material at different temperatures.
The specific heat of a material can vary with the temperature. The vectors specificHeat and temperature
must have the same size to be valid. The data should be linearly interpolated.
Temperature in [K]
Specific heat capacity of the material in [J/(kg*K)]
specificPerformanceMapsType
Collection of all assignments of specific performance maps to selected mission segments
Specific performance map
Applying a specific performance map to selected mission segments. In addition to the obligatory
defaultPerformanceMapUID
at least a
segmentUID
or
pointPerformanceUID
must be given.
UID of performance map to be used for mission segments
List of all mission segment UIDs to which the performance map is to be applied
List of point performance UIDs to which the performance map is to be applied
List of point performance UIDs to which the performance map is to be applied
Speed designators
Provides an enumerated list of V-speeds as defined by regulations.
Design maneuvering speed
Design speed for maximum gust intensity
Design cruise speed, used to show compliance with gust intensity loading
Design diving speed, the highest speed planned to be achieved in testing
Designed flap speed
Stall speed or minimum steady flight speed for which the aircraft is still controllable
Stall speed or minimum flight speed in landing configuration
Stall speed or minimum steady flight speed for which the aircraft is still controllable in a specific configuration
Minimum control speed
Never exceed speed
Maximum operating limit speed
Sphere
The local component coordinate system of the sphere lies in its center.
From there, the "radius" extends to the edge of the sphere.
Radius [m]
Definition of the wings spoilers.
Definition of the wings spoilers.
Spoilers of the wing.
A spoiler is defined via its outerShape relative to the
componentSegment. The WingCutOut defines the area of the upper
skin that is removed by the spoiler. Structure is similar to the
wing structure. The mechanical links between the spoiler and the
parent are defined in tracks. The deflection path is described
in path. Additional actuators, that are not included into a
track, can be defined in actuators.
Name of the spoiler.
Description of the spoiler.
UID of the parent of the spoiler. The parent
is the componentSegment, where the spoiler is attached.
Standard profile
State parameters list
Contains a list of all state parameters.
State parameter definition
Contains the values of a parameter and its uid as reference.
Static power breakdowns
Static power breakdown case
Name
Description
stiffnessType
Storage components
Storage component
Fill factor
Fill factor reference (optimalVolume | usableVolume | realVolume)
Energy carrier configuration
Stored fuels
Stored fuel
stringArrayBaseType
Base type for string array nodes (including maptype
array attribute)
DEPRECATED: As of CPACCS version 3.3, the
mapType
attribute is set to optional to ensure the compatibility of older data records. However, since the type is uniquely defined via the XSD, the attribute is superfluous and will therefore be completely omitted in future versions.
stringBaseType
Base type for string nodes (including external data
attributes)
stringerFramePositionType
Description of individual stringer / frame positions
UID of profile based structural element
x position in absolute value
UID reference to a fuselageSectionElement
y coordinate of reference system
z coordinate of reference system
angle definition to calculate intersection
with loft
Continuity definition for profile extrusion:
0= C0 (allows sharp edges, default), 2= C2 (defines curvature
continuity)
Definition of interpolation between different
profiles: 0= no interpolation 1= interpolation of structural
profile
framePositionUIDs of the frame
A framePostion defines a location where a frame in mounted.
framePositionUID of the frame, where the landing gear
is attached to.
stringersAssemblyType
StringersAssembly type, containing an assembly of
stringers (new V1.5)
arbitraryStringerType
ArbitraryStringer type, containing stringer definition
(CPACS V1.5+)
stringUIDBaseType
This is the base type that links to other components. It should always contain a UID.
This node has an additional attribute isLink that will be used if a stringBaseType refers to a uID. TIXI can then
perform automatic validation for the existence of the referenced uID.
Furthermore this node contains an additional attribute symmetry. The symmetry attribute may take three values: symm, def, full
def: The element refers to the geometric component that has a symmetry attribute and refers only to the defined side of the geometric component.
symm: The element refers to the geometric component that has a symmetry attribute and refers only to the symmetric side of the geometric component. (Similar to the previous _symm solution)
full: The element refers to the geometric component that has a symmetry attribute and refers to the complete component. (This is the default behaviour)
DEPRECATED:
The isLink attribute is set to optional to ensure the compatibility of older data records.
However, since the linking character is explicitly defined by the stringUIDBaseType, the attribute is superfluous and will therefore be completely omitted in future versions.
stringVectorBaseType
Base type for string vector nodes
The vector base type can include optional uncertainty
information. The description of uncertainties is placed in
additional attributes. First, it is described by an attribute that
describes the type of uncertainty function called functionName.
The functionName attribute includes the tag name of the
distribution function which is listened in the table shown below.
Each uncertainty function is further describes by a set of
parameters that are described in the table below.
If the uncertainty values change for the elements of
the vector than the attribute may be written as a list of values
separated by semicolons
DEPRECATED: As of
CPACS
version 3.3, the
mapType
attribute is set to optional to ensure the compatibility of older data sets.
However, since the type is uniquely defined via the XSD, the attribute is superfluous
and will therefore be completely omitted in the next major release (Note: requires
TiXI >= 3.3). Please contact the
CPACS
team
if for any reason you see a long-term need for the
mapType
attribute.
Structural elements
structuralElements Type, containing the different structural
elements
Seat elements (Deprecation warning: This element will soon be removed from the official CPACS. Use the new seat modules located at cpacs/vehicles/deckElements!)
Structural mount
In order to place non-structural masses in a model, it is necessary to define where these masses are attached to the structure.
For example, you want to model a heavy on-board system, a piece of payload, a fuel tank, an engine, etc. as a fixed point mass.
The first step would be to create a mass point at the center of gravity of your component.
For some components this is directly available, the a fuel tank you would evaluate the volume and fill rate from its CPACS definition to get the CoG.
The next step is to connect the mass point to the structure in a physically meaningful way to properly introduce any inertial loads generated by that mass into the structure. This purpose is fulfilled by the structural mounts. The logic of these mounts is to identify points or lines in the geometry created by the intersection of two referenced structural components ("fromStructureUID" and "toStructureUID"). These points or lines are then connected to the center of gravity of the mass point. The reasoning behind this is that the intersections between two structural objects (e.g., rib and spar) usually represent locations in the model that are stiff enough to support the additional loads from any equipment.
For example, the following figure shows a heavy system represented by a generic sphere attached to the structure by three structural mounts:
From left to right:
The leftmost attachment uses the end points of the intersection line between the starboard wall and the forward bulkhead.
The middle attachment uses all points (here only 7 points are drawn for visualization) on the intersection line between the middle wall and the front bulkhead.
The rightmost attachment has a similar definition to the left one, using the end points of the intersection line between the port wall and the front bulkhead.
When creating a structural FEM model of this CPACS representation, a rigid body element (e.g. Nastran RBEx) can be generated based on the yellow lines.
This is used, for example, to attach landing gear struts to the aircraft structure.
In short, structural mounts identify points or lines by intersecting two structural components, the resulting points or lines are then attached to a third component that references this structural mount as its attachment.
Typically, as in the example above, components reference more than one structural mount as their attachment points.
If this value is set to true then only the end points of the intersection shall be included as nodes in the model.
The UID for the first connection UID may include for wings: skin, sparUID, ribDefinitionUID, ribNumber, stringerUID, stingerNumber, and for fuselages: skinSegmentUID, frameUID, stringerUID, crossBeamUID, crossBeamStrutUID, longFloorBeamUID.
Optional counter to specify numbered items, e.g. ribs in a ribSet.
The UID for the second connection UID may include for wings: skin, sparUID, ribDefinitionUID, ribNumber, stringerUID, stingerNumber, and for fuselages: skinSegmentUID, frameUID, stringerUID, crossBeamUID, crossBeamStrutUID, longFloorBeamUID.
Optional counter to specify numbered items, e.g. ribs in a ribSet.
structuralProfile3DType
Definition cross sections of structural profiles.
Structuralprofiles type, containing cross section
information of structural profiles.
2-dimensional cross sections of structural profiles.
StructureProfile type, containing data of a structure
profile cross sections. The cross section profile is defined by
several points (->pointList) in the x-y-space. Two points are
combined to one sheet (->sheetList) by using the pointUIDs.
This profile is defined by several points in the
x-y-space. Always two points are combined to one sheet. The
properties of each sheet are defined in the 'sheetProperties'
section by referencing on the sheetUID and the material
properties. The orthotropy direction of composite materials equals
the x-sheet axis. The orthotropy direction angle equals a positive
rotation around the z-sheet axis as indicated in the picture below
(part 3.), where a wing stringer is defined as an example:
Name of the structure profile.
Description of the structure profile.
List of structural profile points, only x and
y.
Structural wall reinforcement definition specifying physical properties of a fuselage wall segment.
Reference to a sheet element definition specifying the physical properties of the wall's shell.
Reinforcements running along the position polygon of the wall positions.
Reinforcements running in lateral/radial direction in the wall segment plane.
Reinforcement at inner side of wall. This is either, depending on the extrusion direction flag, the edge of the wall that connects the positions ("positiveDirection") or the edge of the wall where the wall intersects with the fuselage skin in the opposite direction of the extrusion direction.
Reinforcement at outer side of wall. The outer side of the wall is defined as the edge of the wall at the intersection of the wall with the fuselage skin running along the main direction of the wall.
Lateral caps are the reinforcements of
the wall at the edges lateral to the
main direction of the wall. These caps
can be either defined at start, end,
start and end or at all wall positions
according to the placement flag.
Strut assembly
Geometric description, spatial placement and specification of material parameters
Strut properties
The starting point of the support strut must connect to the main strut. This element specifies the relative position on the main strut (0 -> top end, 1 -> bottom end).
End position in absolute coordinates. Coordinates are relative to parent if it has a parentUID reference (otherwise global).
End position in eta/xsi/relHeight coordinates
End position as a relative position on another strut of this landing gear
Attachment to an aircraft wing or fuselage component
Reference to an actuator uID
Strut properties
Geometric description and material properties
of a strut
(Outer) radius of the strut
Material of the strut
Inner radius of the strut
Reference to structural element for a more
detailed cross section definition
Geometric description and material properties of a strut
Length of the strut
Design study parameters and results
Contains optimization data such as definitions of design parameters and design studies.
subFleetsType
Contains a list of different sub fleets
subFleetType
Each fleet can be divided into sub fleet groups
Name of fleet
Description of the fleet
A ; separated list of all tailsign strings
subLoadType
Superellipse
A profile based on superellipses is composed of an upper and a lower semi-ellipse, which may differ from each other in their parameterization.
The total width and height of the profile is always 1, since scaling is performed after referencing (e.g., in the fuselage).
This lowerHeightFraction describes the portion of the lower semi-ellipse on the total height.
The resulting profile is defined by the following set of equations:
with
The following examples indicate the various possibilities of parametric profiles:
Example 1:
(mUpper,nUpper,mLower,nLower, lowerHeightFraction) = (0.5; 2; 5; 3; 0.25)
Example 2:
(mUpper,nUpper,mLower,nLower, lowerHeightFraction) = (2; 2; 2; 2; 0.5) = a circle
Example 3:
(mUpper,nUpper,mLower,nLower, lowerHeightFraction) = (1; 1; 1; 1; 0.5) = a square / diamond
Note: For exponents that are infinitely large, the superellipse converges to a rectangle.
However, the value Inf is not a valid entry at this point.
Use the square element instead.
Exponent m for upper semi-ellipse
Exponent n for upper semi-ellipse
Exponent m for lower semi-ellipse
Exponent n for lower semi-ellipse
Fraction of height of the lower semi-ellipse relative to the total height
Main landing gear support beam
Definition of the main landing gear support beam, if a
support beam is used for the attachment. The definition includes
cross section properties as well as the position of the support
beam.
Symmetry (see CPACS root node documentation for details)
Symmetry inheritance from parent element disabled
Symmetry inherited from parent element (default behavior, i.e. also applies if attribute not set)
Symmetry w.r.t. the x-y plane of the CPACS coordinate system
Symmetry w.r.t. the x-z plane of the CPACS coordinate system
Symmetry w.r.t. the y-z plane of the CPACS coordinate system
System architectures
System architecture
Name
Description
ATA Chapter | generic
Connections
Connection
Name
Description
Type of the connection.
Control devices
Control function indicating the activation state
System elements
Control parameter definition for System or Connection state
Control parameter indicating active state
Control parameter indicating inactive state
Systems
Systems type, containing the aircraft's control system
data
Please see the attached picture for further
documentation
Node for geometrical layout of system components
based on simple geometric shapes
Cockpit controls, e.g. stickRoll, pedals
Different commandCases that are commanded,
e.g. roll, accelerate
Control Distributors, deliver inputs to the
control actuators. E.g. different angles of different ailerons.
Control laws, for regulated actuation
tailplaneAttachmentAreaType
tailplaneAttachmentArea type, containing dat on
fuselage
structure to attach tailplaine
Definition of tailplane attachment area
(Standard
Configuration)
type of tailplane attachment: Currently
restricted to
'Type1' and 'Type2' (see documentation)
Definitions of VTP interface
Definitions of VTP interface
takeoffPerformanceParametersType
Take-off distance at liftoff speed VLOF.
Take-off distance at safety speed V2.
Optimal speed Velev at point of initiating
take-off rotation by elevator deflection for a minimum take-off
distance.
Optimal rotation speed VR for a mini-mum
take-off distance
Liftoff speed VLOF.
Safety speed V2.
Take-off decision speed V1
Minimum control speed ground VMCG.
Flight path angle being achieved at V2 with
one engine failure in 400 ft height above ground. This is the
result of a post trim calculation using the deter-mined V2. If
the trim calculation fails the entry is set to -90.
Structural properties of the tangent links, if
existing. The tangent links do connect the engine pylon with the
engine to carry the thrust forces.
simpleConnectionsType
SimpleConnections type, containing simple connections
simpleConnectionType
SimpleConnection type, containing a simple connection
Can be each structural member (skinSegment,
stringer, frame, paxCrossBeam, cargoCrossBeam,
paxCrossBeamStrut, cargoCrossBeamStrut, long. floor beams,
floorPanel, seatModule)
Can be each structural member (skinSegment,
stringer, frame, paxCrossBeam, cargoCrossBeam,
paxCrossBeamStrut, cargoCrossBeamStrut, long. floor beams,
floorPanel, seatModule)
timeBaseType
Base type for time nodes (including external data attributes)
This time type is based on the xsd:time definition.
"To specify a time zone, you can either enter a time in UTC time by adding a "Z" behind the time - like this: 09:30:10Z
or you can specify an offset from the UTC time by adding a positive or negative time behind the time - like this:
09:30:10-06:00
or
09:30:10+06:00" (description taken from http://www.w3schools.com/xml/schema_dtypes_date.asp)
timeConstraintBaseType
Base type for time nodes including a relational operator attribute indicating valid constraint region
The timeConstraintBaseType extends the timeBaseType and thus inherits all its attributes.
Toolspecific data
This type contains a list of tools each specifying some basic tool information as well as the actual toolspecific part.
The toolspecific elements must be defined in a separate namespace which can be specified and linked with the corresponding XSD file
in the CPACS header:
<cpacs xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="pathToSchemaFile/cpacs_schema.xsd"
xsi:schemaLocation="http://www.cpacs.de/myTool pathToToolspecificSchemaFile/toolspecific_myTool.xsd">
A simple example could look like this:
<toolspecific>
<tool>
<name>myToolName</name>
<version>1.2.3</version>
<myTool xmlns="http://www.cpacs.de/myTool" schemaVersion="1.0">
<parentElement>
<childElement1>stringValue</childElement1>
<childElement2>1.0</childElement2>
</parentElement>
</myTool>
</tool>
</toolspecific>
Tool identification
Tool information as described in the toolspecificType.
Name of the tool
Version of the tool
Wildcard for the root element of a toolspecific namespace
topologyEntriesType
topologyEntryType
A topology entry is used to combine the dynamic aircraft
models of several components, e.g. wing and fuselage. By default
these will be stiff. If desired stiffness and rotation with
respect to the CPACS coordinate system may be specified.
Torispherical dome
R1: dish radius
R2: knuckle radius
totalOperatingCostType
trackActuatorType
Reference to the uID of the actuator of the
track.
Definition of the material properties of the
actuator to track attachment.
Joint coordinates
Definition of a joint coordinates.
Joint name (P1|P2|..|P8)
Specification of joint coordinates.
Specification of joint coordinates.
Set of joint coordinates
Definition of a set of joint coordinates.
Value of the command parameter of a control distributor. If not given explicitly in the control distributor, linear interpolation between the neighboring points is required.
wingSparsType
Spars type, a spar is defined by sparSegments that
stretch between multiple sparPositions
Definition of the struts of a control surface track.
Definition of the struts of a control surface track.
Definition of a strut of a control surface track.
Definition of a strut of a control surface track.
Definition of the wings trailing edge devices.
Definition of the wings trailing edge devices.
Trailing edge device of the wing.
A trailingEdgeDevice (TED) is defined via its
outerShape relative to the componentSegment. The WingCutOut
defines the area of the skin that is removed by the TED.
Structure is similar to the wing structure. The mechanical links
between the TED and the parent are defined in tracks. The
deflection path is described in path. Additional actuators, that
are not included into a track, can be defined in actuators.
Leading and trailing edge are defined by the outer
shape of the wing segments, i.e. the trailing edge of a
trailingEdgeDevice is the trailing edge of the wing. This is also
valid for kinks that are present in the wing but not explicitly
modeled in the control surface.
The edges of the control surface within the wing are a
straight line in absolute coordinates! Hence, there needs to be a
straight connection between the eta-wise outer and inner points
of the edge that is within the wing in absolute coordinates.
Name of the trailing edge device.
Description of the trailing edge device.
UID of the parent of the TED. The parent can
either be the uID of the componentSegment of the wing, or the
uID of another TED. In the second case this TED is placed within
the other TED (double slotted flap). In this way n-slotted TEDs
can be created.
Definition of cruise rollers/mid-span stops.
Those features are small rolls at the leading edge of a flap
that keep the flap within the bending wing at cruise
configuration.
Definition of interconnection struts. Those
struts connect two neighbouring flaps and are load carrying in
case of an actuator of flap track failour.
Definition of z-couplings. Those elements
couple two neighbouring flaps in z-direction.
Trajectories
trajectoryGlobalType
trajectoryType
2D transformation
Scaling of the structural profile
rotation around z-axis of profile definition
translation of profile definition
Transformation
Transformation type, containing a set of
transformations. The order of the transformations is scaling
-> rotation -> translation, and they are executed in this
order. Any of them can be omitted; it will be replaced by its
defaults.
Transformations are always executed relative to the
child not the parent. I.e. a scaling does not have an influence
on the parent item. For example in the outer geometry of a wing
the element scaling does not influence the section. Scaling does
also not effect rotation and translation.
Scaling data default: 1,1,1. Those parameters
describe the scaling of the x-, y-, and z-axis.
Rotation data default: 0,0,0. The rotation
angles are the three Euler angles to describe the orientation of
the coordinate system. The order is always xyz in CPACS.
Therefore the first rotation is around the x-axis, the second
rotation is around the rotated y-axis (y') and the third
rotation is around the two times rotated z-axis (z'').
Translation data default: 0,0,0. Translations
can either be made absolute in the global coordinate system
(absGlobal) or absolute in the local Coordinate system (absLocal).
Scaling
Rotation
Translation
Rotation
Translation
Translation
Transformation
Transformation type, containing a set of
transformations. The order of the transformations is scaling
-> rotation -> translation, and they are executed in this
order. Any of them can be omitted; it will be replaced by its
defaults.
Transformations are always executed relative to the
child not the parent. I.e. a scaling does not have an influence
on the parent item. For example in the outer geometry of a wing
the element scaling does not influence the section. Scaling does
also not effect rotation and translation.
Scaling data default: 1,1,1. Those parameters
describe the scaling of the x-, y-, and z-axis.
Rotation data default: 0,0,0. The rotation
angles are the three Euler angles to describe the orientation of
the coordinate system. The order is always xyz in CPACS.
Therefore the first rotation is around the x-axis, the second
rotation is around the rotated y-axis (y') and the third
rotation is around the two times rotated z-axis (z'').
Translation data default: 0,0,0. Translations
can either be made absolute in the global coordinate system
(absGlobal) or absolute in the local Coordinate system (absLocal).
System breakdown data
Specification of the power breakdown case
UID of the corresponding trajectory
Power breakdowns
Power breakdown case along a trajectory
Name
Description
transmissionGearRatioType
TransmissionGearRatio type, defining the ratio of
output rotation velocity to input rotation velocity.
transmissionShaftInputsType
TransmissionShaftInputs type, defining the shaft inputs
of a transmission.
transmissionShaftInputType
TransmissionShaftInput type, defining a shaft input for
a transmission.
transmissionShaftOutputsType
TransmissionShaftOutputs type, defining the shaft
outputs of a transmission.
transmissionShaftOutputType
TransmissionShaftOutput type, defining a shaft output
for a transmission.
transmissionsType
Transmissions type, containing all the
transmissions/gearboxes of a rotorcraft model.
transmissionType
Transmission type, defining a transmission/gearbox.
Trim case
Name
Description
UID of trim requirement
Description of the linear model
Trim requirements
Contains a list of trim requirements
Trim requirement
Name
Description
UID of a predefined flight point
UID of weight and balance description
Trim
Provides a list of trim cases
Turbo generators
Turbo generator
UIDGroupDefinitionsType
UIDGroupDefinitionType
List of uIDs
Reference to a uID
Structural properties of the upper links, if existing.
The upper links do connect the upper forward part of the pylon
box with the forward wing attachment.
List of segments that are allowed to be varied within a mission optimization.
Provides a list of segments having variable conditions within the segmentBlock.
Example: a segmentBlock containing takeOff, climb, cruise, decent, landing segments has a cruise segment for which the range is variable.
The range of this segment is then to be calculated using the range defined for the segmentBlock while concerning the known ranges of all
other segments within the segmentBlock.
This concept needs to be practically tested. Does it suffice to mention (a list of) segments that are free to change to fit the overall block constraints? What happens if a segment is variable, though it has some constraints? When to define a segment as variable (climb until endPosition z, then endPosition x should be left free. Is the segment then variable? Probably not.). Somehow the 'free' segment should be in between fully defined segments (i.e.: a cruise+descent in between endPosition z == ICA and endPosition z == 0 for landing to define max range. How to define this exactly?)
variableSegmentType
Containing the definition of variable segments for a segment block
defines uID of the segment having variable conditions
defines which condition(s) are variable within the segment (must be one of the defined endConditions for the segmentBlock)
System element
Name
Description
Vehicles
The vehiclesType contains all vehicle-specific data.
This includes the vehicle itself (i.e. aircraft and rotorcraft).
Furthermore, components (e.g. engines, structuralElements, etc.)
as well as physical properties of materials and fuels can be predefined for easy and consistent reuse via uID-references.
Version Informations
Version Information
CPACS version of the dataset
Description of CPACS dataset
Timestamp of initial CPACS dataset creation
Creator of initial CPACS dataset
vtpFrameDefType
Definition of the individual VTP attachments
Definition of tailplane attachment area
(Standard Configuration)
UID of the fuselage frame at this VTP
attachment
Flag for option for VTP attachment between
defined FrameUID and the next one
UID of panel element at VTP attachment (shell
elements)
UID of structural element at VTP attachment
(base, beams)
UID of structural element at VTP attachment
(horizontal, beams)
UID of structural element at VTP attachment
(radial, beams)
vtpInterfaceDefType
Definition of the interface of the VTP
Definition of the VTP interface
Definition of the VTP attachment frames and
their
reinforcement
Defines area for valid x-position of VTP (just
used
if attachmentpoint is directly based on frame) ==> check and
potentially warning message
Definition of the max. distance between
fuselage and
the defined VTP pins ==> check and potentially warning
message
Definition of reinforcement area at VTP frame
positions (relative coordinate, smaller than
1.0)
Definition of vertical reinforcements at VTP
frame
positions (relative coordinate, smaller than
1.0)
value to change from horizontal to radial
reinforcements for VTP frame plates
UID of elements to connect VTP pins with
fuselage
(beam elements)
Definition of wall positions to place walls inside fuselage.
Wall position definition specifying a point in the fuselage to be connected to a wall segment.
Definition of a wall position to place walls inside fuselage.
UID of a bulkhead determining the
x-coordinate of the position with the given
y- and z-coordinates.
UID of a wall segment determining the
x-coordinate of the position with the given
y- and z-coordinates.
UID of fuselage section determining the
x-coordinate of the position with the given
y- and z-coordinates.
Absolute x-coordinate of wall position in fuselage coordinate system.
Absolute y-coordinate of wall position in fuselage coordinate system.
Absolute z-coordinate of wall position in fuselage coordinate system.
Reference to wall position uID.
Wall segment definition.
Defines extrusion direction. Rotation angle
around fuselage x-axis of extrusion direction. A
value of 0deg means fuselage z-axis as extrusion
direction. Default: 0.0deg.
By default, the wall is only extruded in positive direction. If doubleSidedExtrusion is true, the wall is additionally extruded in negative direction as well. Default: false.
Rotates the first edge of the wall segment so that it is adjacent with the structural element defined in the first wall position (bulkhead, fuselage section or another plane wall). Default: false.
Rotates the last edge of the wall segment so that it is adjacent with the structural element defined in the last wall position (bulkhead, fuselage section or another plane wall). Default: false.
A list of uIDs referencing other
structural/geometric elements that shall serve
as a boundary of the wall element. Possible
references are floor, wall or
genericGeometryComponent. A major requirement is
that the referenced element has an intersection
with the wall for at least the distance between
two wall positions. So that a full geometric
face of the wall is bounded by it. Neighbouring
wall faces that are not completely bounded by
the reference element are not affected.
Reference to the structural property definition
of this wall segment.
List of wall position uIDs that are used for
this wall segment. At least two positions must
be defined (for start and end position of wall).
If more than two positions are referenced here,
the wall is constructed out of several planar
faces that connect two consecutive positions
(Note: Order of position uIDs defines
connectivity).
Definition of wall positions to place
walls inside fuselage.
List of wall segments.
webType
SparWeb type, containing the cross section area of the
spar web and the material properties.
Please find below a picture where all spar cross
section parameters as well as the orientation references for
the material definition can be found:
Material definition of the spar web.
relPos ranges from 0 to 1 It defines the
position of the web relative to the caps (see picture below)..
weightAndBalanceCaseType
WeightAndBalanceCase type, containing weight and
balance data for one case
weightAndBalanceFuelInTanksType
weightAndBalanceFuelInTankType
Ranges from 0 for empty tank to 1
weightAndBalanceFuelType
weightAndBalancemCargosType
For a higher ganularity it is possible to add more
information on the actual Cargo that are included in the
operational case. Please note that the information needs to be
identical with the massBreakdown. Hence, only links via uIDs can
be specified.
weightAndBalancemPaxxType
For a higher ganularity it is possible to add more
information on the actual Pax that are included in the
operational case. Please note that the information needs to be
identical with the massBreakdown. Hence, only links via uIDs can
be specified.
weightAndBalancePayloadType
Weight and balance
WeightAndBalance type, containing weight and balance
datasets
Definition of the landing gear wheel.
The center plane of the wheel is located on the end point of the axle.
Wheel radius
With of the wheel
Brake: false =
not braked; true = braked.
windowAssemblyPositionType
WindowAssembly type, containing an the position of a
windows assembly
UID of the window element to be used
x position of window element on global x axis
z position of window element reference point
angle around global x axis to define window
position with respect to positionX and postionZ
windowsAssemblyType
WindowsAssembly type, containing an assembly of windows
windowsType
Windows type, containing windows
wingAeroPerformanceType
wingAeroPerformance type, containing performance maps
with aerodynamic data of a wing.
Reference to the uID of the analysed wing
References used for the calculation of the
force and moment coefficients of the wing (in the wing axis
system!)
Calculated aerodynamic performance maps of the
wing
wingAirfoilsType
WingAirfoils type, containing wing airfoil geometries.
See profileGeometryType for further documentation
Position of the landing gear on a wing
Definition of the position of the landing gear
(intersection point of main strut and pintle sturt) on a wing,
using relative componentSegment coordinates
Relative height of spar or rib at which landing gear is attached.
Relative spanwise position (eta) of spar at which landing gear is attached.
Relative chordwise position (xsi) of the rib at which landing gear is attached.
Cells of the wing.
WingCells type, containing all the cells of the wing.
Cell of the wing
A cell defines a special region of the wing. Within
this region skin and stringer properties can be defined that
differer from the properties of the rest of the wing. In general
a cell is defined by defining four borders – the cell leading
and trailing edge and the inner border and the outer border.
Those borders can either be defined by using eta/xsi coordinates
or by referencing to spars and ribs. Mixed definitions (e.g.
forward border is defined due to a spar, side borders due to eta
coordinates) is allowed. In general a cell is quadrilateral. But
if e.g. the spar, which is used for the definition of the
trailing edge, has a kink, the cell can have more than four
corners.
The cell leading and trailing edge (= forward and rear
border) can either be defined by referencing to a spar
(->sparUID) or by the defining the xsi (=relative chord)
coordinates of the border (xsi1 = inner end; xsi2 = outer end).
The cell inner and outer border can either be defined
by referencing to a rib (->ribDefinitionUID and ribNumber) or
by the defining the eta (=relative spanwise) coordinates of the
border (eta1 = forward end; eta2 = rear end).
Some examples for wing cells can be found in the
picture below:
Structure of the wing
wingComponentSegmentStructure type, containing the
whole structure (skins, ribs, spars...) of the wing.
CutOuts of the wing
CutOut of the wing
A wing cutout is defined using any combination of eta-xsi-spar-rib-uids.
It has the similar syntax to a wingCell.
The cell leading and trailing edge (= forward and rear
border) can either be defined by referencing to a spar
(->sparUID) or by the defining the xsi (=relative chord)
coordinates of the border (xsi1 = inner end; xsi2 = outer end).
The cell inner and outer border can either be defined
by referencing to a rib (->ribDefinitionUID and ribNumber) or
by the defining the eta (=relative spanwise) coordinates of the
border (eta1 = forward end; eta2 = rear end).
Some examples for wing cells can be found in the
picture below:
Type of the cutout (upper|lower|both): upper shell, lower shell or both.
Elements of the wing.
WingElements type, containing the elements of a wing
section.
Element of the section.
Within elements the airfoils of the wing are defined.
Each section can have one or more elements. Within each element
one airfoil have to be defined. If e.g. the wing should have a
step at this section, two elements can be defined for the two
airfoils.
Mathematically spoken a element is a coordinate system
that is translated, rotated and scaled relative to the section
coordinate system. This transformation parameters are defined
within the transformation section. The wirfoil, which is linked
by using the parameter airfoilUID is directly 'copied' in the
element coordinate system. If e.g. the airfoil is defined from 0
to 1 in x-direction and the total scaling of the elements x-axis
equals 3.5 the wing chord is 3.5 m long.
An example for wing element can be found in the
picture below:
Name of the wing element.
Description of the wing element.
Reference to a wing airfoil.
Border of the fuel tank (either rib or spar).
Spar uID of the bordering spar.
UID of the rib set of the bordering rib.
RibNumber of the rib set of the bordering
rib.
Definition of the geometry of the wing fuel tank by
defining a continouse list of borders.
List of wing fuel tanks.
Definition of one wing fuel tank.
Name of the wing fuel tank.
Description of the wing fuel tank.
Definition of the wing-fuselage attachment.
Definition of the wing-fuselage attachment
Definition of the wing-fuselage attachment
Definition of the wing-fuselage attachment. The area
of the fuselage attachment (resp. center wing box, CWB) is
defined by defining one resp. two ribs from the rib definition.
If one rib is defined (rib1) the CWB goes from the closer end of
the componentSegment (e.g. wing symmetry plane) to the defined
rib. If two ribs are defined (rib1 and rib2), the CWB is between
both ribs.
Additionally attachment pins can be defined. At those
positions the wing is attached to the fuselage. This can be e.g.
used for defining the wing-attachment of high wing
configurations, HTPs or VTPs.
Definition of first (=inner) rib of the
fuselage attachment.
Definition of the second (=outer) rib of the
fuselage attachment. Optional. Only to be used if attachment is
defined over two ribs.
Definition of position, orientation, materials
and blocked DOFs of attachment pins.
Definition of actuators (e.g. trim actuator of
an HTP) of the attachment.
wingInterfaceDefinitionsType
CenterFuselage high wing interface definitions
centerFuselageMainFramesType
High wing main frame definition, containing mainframe
UIDs
wingInterfaceSupportStrutsAssemblyType
wingInterfaceSupportStrutsAssembly type, containing
support struts assembly
wingInterfaceSupportStrutType
wingInterfaceSupportStrut type, containing support
strut definition
Name of support strut.
Type description: lateral or longitudinal
support strut.
IntermediateStructure cells
Definition of the intermediateStructure of the
componentSegment of the wing.
Definition of the cell of the intermediateStructure
IntermediateStructure:
It defines the filling materials between the upper and
lower shell (e.g. honeycombe structures in a smeared
representation). IntermediateStructure is optional.The position
of the intermediateStructure is defined in so called cells (=
special areas on the wing). Default is no intermediateStructure.
Material Definition of intermediateStructure:
The material of the intermediateStructure is reference
by 'material'. The material orientation is defined by 'rotX' and
'rotZ'. 'rotZ' is defined equivalent to the stringer angle resp.
the skin orthotropyDirection. 'rotX' equals a positive rotation
around the wings x-axis, while a rotation of zero is equivalent
to the wing middle plane.
A picture to clarify the reference direction of rotZ
(equivalent to orthothropy direction of the wing) can be found
in the picture below:
Position definition by using cells:
A cell defines a special region of the wing. Within
this region the cell properties are defined. In general a cell
is defined by defining four borders – the cell leading and
trailing edge and the inner border and the outer border. Those
borders can either be defined by using eta/xsi coordinates or by
referencing to spars and ribs. Mixed definitions (e.g. forward
border is defined due to a spar, side borders due to eta
coordinates) is allowed. In general a cell is quadrilateral. But
if e.g. the spar, which is used for the definition of the
trailing edge, has a kink, the cell can have more than four
corners.
The cell leading and trailing edge (= forward and rear
border) can either be defined by referencing to a spar
(->sparUID) or by the defining the xsi (=relative chord)
coordinates of the border (xsi1 = inner end; xsi2 = outer end).
The cell inner and outer border can either be defined
by referencing to a rib (->ribDefinitionUID and ribNumber) or
by the defining the eta (=relative spanwise) coordinates of the
border (eta1 = forward end; eta2 = rear end).
Some examples for wing cells can be found in the
picture below:
Reference to the material of the intermediate
structure.
'rotX' equals a positive rotation around the
wings x-axis, while a rotation of zero is equivalent to the wing
middle plane direction.
'rotZ' is defined equivalent to the stringer
angle resp. the skin orthotropyDirection.
Definition of a ribCell
RibCells are optional elements. They are defined via a
fromRib and a toRib. The enumeration is within the ribSet.
RibNumber 1 starts at etaStart.
Defines the beginning of the ribCell. The
enumeration is within the ribSet.
Defines the ending of the ribCell. The
enumeration is within the ribSet.
WING: The Rotation along the x describes a
rotation around a line, that is defined by the intersection of
the rib with the wing middle plane (orientated from leading to
trailing edge). This angle defaults to 90° which means, that the
rib is perpendicular on the wings middle plane. PYLON: The
Rotation along the z describes a rotation around the pylons
z-axis (= rotation in top view). This angle defaults to 90°
which means, that the rib is perpendicular to the pylons x-axis.
The orthotropyDirection is defined as rotation
around the ribs z-axis. The rib coordinate system is defined as
follows: x-axis is from leading to trailingeEdge of the
componentSegment in the direction of the rib elongation. z-axis
is normal to the rib in the direction of positive eta. y is
defined by right hand rule. Rotation is around the z-axis. Zero
degrees are at the x-axis positive direction.
Cross section properties of a wing rib
wingRibCrossSectionType, containing the definition of
ribsCrossSection
The orthotropyDirection is defined as rotation
around the ribs z-axis. The rib coordinate system is defined as
follows: x-axis is from leading to trailingeEdge of the
componentSegment in the direction of the rib elongation. z-axis
is normal to the rib in the direction of positive eta. y is
defined by right hand rule. Rotation is around the z-axis. Zero
degrees are at the x-axis positive direction.
WING: The Rotation along the x describes a
rotation around a line, that is defined by the intersection of
the rib with the wing middle plane (orientated from leading to
trailing edge). This angle defaults to 90° which means, that the
rib is perpendicular on the wings middle plane. The rotation
angle is defined at the intersection point of the rib with the
ribReference line. The rib itself is always straight and not
twisted. PYLON: The Rotation along the z describes a rotation
around the pylons z-axis (= rotation in top view). This angle
defaults to 90° which means, that the rib is perpendicular to
the pylons x-axis.
Post element definition applied to all vertical intersections with spars
Explicit positioning of a wing rib
Use this type for an explicit positioning of a rib. As opposed to
ribsPositioning, this defines a single rib connecting a specified start
and end point.
Defines the start of the rib defined in eta-xsi coordinates of a reference plane
Defines the start of the rib defined by a point on a reference curve
such as a spar, but not an explicit sparPosition
Defines the location of the beginning of the rib using a specific sparPosition.
Defines the end of the rib defined in eta-xsi coordinates of a reference plane
Defines the end of the rib given by a point on a reference curve
such as a spar, but not an explicit sparPosition
Defines the location of the end of the rib using a specific sparPosition.
Defines the forward beginning of the ribs. It can either be a
sparUID or "trailingEdge" or "leadingEdge".
RibEnd defines the backward ending of the ribs. It can either be a
sparUID or "trailingEdge" or "leadingEdge".
wingRibPointType
The wingRibPointType is used to define reference points on ribs.
It can be used for rib set definitions (wingRibsPositioningType) as
well as explicit rib definitions (wingRibExplicitPositioningType).
The UID of the rib definition. Can be a reference to nodes
of either wingRibsPositioningType or wingRibExplicitPositioningType.
For references of type wingRibsPositioningType this node indicates the rib number of the rib set.
If not given it defaults to 1.
Normalized xsi coordinate of the rib point which is measured along the rib
from the start point [0] towards the end point [1].
Wing ribs
RibDefinitions type, containing the definition of all
ribs of the wing.
Definition of a set of ribs
RibDefinitionType, containing the definition for ribs.
Ribs are defined in sets of one or more ribs. The positions of
the rib, as well as the orientation of the ribs are defined in
'ribPositioning'. The cross section properties, as e.g.
materials, are defined in 'ribCrossSection'.
Name of the rib set
Description of the rib set
Positioning of a set of wing ribs
The ribsPositioning type allows the definition of a set
of ribs which is distributed over a specified spanwise area.
The positions of the ribs are defined by placing the
ribs on a reference line on the wing (ribReference). The inner
and the outer beginning of the rib set is defined using etaStart
and etaEnd. The position of the forward and rear end of the ribs
is defined by ribStart and ribEnd. The orientation of the ribs
is defined in ribRotation. The number of ribs of the current rib
set is either defined by ribNumber or by spacing.
Three examples how ribs can be placed on the wing are
illustrated in the picture below. For more detailed information,
please refer to the description of each parameter.
Defines the start of the rib defined in eta-xsi coordinates of a reference plane
Defines the start of the rib by a point on a reference curve,
such as a spar, but not an explicit sparPosition
Defines the location of the beginning of the rib using a specific sparPosition
Defines the end of the rib defined in eta-xsi coordinates of a reference plane
Defines the end of the rib defined by a point on a reference curve
such as a spar, but not an explicit sparPosition
Defines the location of the end of the rib using a specific sparPosition
Defines the forward beginning of the ribs. It can either be a
sparUID or "trailingEdge" or "leadingEdge".
Defines the backward ending of the ribs. It can either be a
sparUID or "trailingEdge" or "leadingEdge".
The spacing of the ribs defines the distance between two ribs,
measured on the
ribReferenceLine. First rib is placed at etaStart.
Defines the number of ribs in this ribSet. First rib is at
etaStart on the
referenceLine, last rib is at etaEnd. The spacing is constant on the
ribReferenceLine.
The ribReference is the reference line for the computation of the rib set spacing.
It can either be a sparUID or "trailingEdge" or "leadingEdge"
RibCrossingBehaviour can either be 'cross' or 'end'. If it is set to'end' the ribs
of this rib set will end at the intersection with another rib.
If it is set to
'cross' the ribs of this rib set will continue at the intersection
with another rib.
wingsAeroPerformanceType
wingsAeroPerformance type, containing
wingsAeroPerformance
Sections of the wing.
WingSections type, containing all the sections of the
wing.
Section of the wing.
WingSection type, containing a wing section. The
sections contains elements, where the airfoils are defined. For
the definition of a wing at least two sections (root and tip)
have to be defined, but any number greater than 2 is also
possible.
Mathematically spoken a section is a coordinate system
that is translated, rotated and scaled relative to the wing
coordinate system. This transformation parameters are defined
within the transformation section.
In addition to the translation, which is defined in
the transformation part, the section can be translated by using
the positionings vectors (wing->positiongs). Translation of
the positionings vectors is added to the translation of the
section.
An example for wing sections can be found in the
picture below:
Name of wing the wing section.
Description of the wing section.
Segments of the wing.
WingSegments type, containing all the segments of the
wing.
Segment of the wing.
A segment defines which two wing elements (=cross
sections) are linked to one wing segment.
An example for wing segments can be found in the
picture below:
Name of wing the wing segment.
Description of the wing segment.
Reference to the element from which the
segment shall start.
Reference to the element at which the segment
shall end.
Optional and additional guidecurves to shape
the outer geometry.
Shells of the wing
Within the wingShellType the upper and lower skin of a
and the skin stringers are defined. At 'skin' and 'stringer' the
skin and stringer properties of the complete componentSegment are
defined. If different skin or stringer properties should be
defined in a special region of the wing this can be done within
'cells'.
If the stringer should not be defined explicitly, they
can be defined implizite by defining an equivalent material layer
and using a composite as material.
Material properties of the wing skin.
The wingSkinType describes the material properties of
the wing.
For composites materials: the positive z-direction is
from the outer side to the inner side.
For composites materials: the reference axis for the
orthotropyDirection is defined by the two leading edge points of
the 'from'- and the 'to'-element of the componentSegment
definition. The angle between the reference axis and the
orthotropyDirection equals the rotation around the z-reference
axis. For details, please refer to the picture below:
Material properties of the wing skin.
Wing spars
Spars type, a spar is defined by sparSegments that
stretch between multiple sparPositions. The spar definition is
very flexible in CPACS. Spars can start and end at any position
of the wing, spars can have kinks at any position of the wing
and spars can cross each other or merge.
At first the spar points (->sparPositions) have to
be defined. Spar points are defined using the relative
coordinates eta and xsi. Spar points do lay on wing middle
plane.
Two or more spar points are connected to on spar
segment (->sparSegments). Each spar segment can be seen as
one spar. The spar geometry between two spar points is defined
as a direct/straight connection in global coordinate system
and not in eta xsi coordinates of the component segment.
One spar point can be used by more than one spar, if
e.g. two spars are merging. The detailed cross section of the
spar is also defined with sparSegments.
Please find below a picture for an example definition
of 3 spars in one wing, by using spar position points and spar
segments:
Definition of the wing stringers.
Within the wingStringerType wing stringers are
defined. The stringer are defined by referencing on the
stringerStructureUID, where the shape and material settings of
one single stringer is defined. In addition the orientation and
the stringer pitch have to be defined:
One stringer intersects the point at the given xsi and
eta position.
Alternatively, an explicit stringer definition can be
applied if the stringers shall be tapered.
This is the simple and default stringer
definition
The pitch describes the distance between to
adjacent stringers in the plane rectangular to the stringer
elongation direction.
Stringer angle: the reference axis for the
stringer angle is defined by the two leading edge points of
the 'from'- and the 'to'-element of the componentSegment
definition. The angle between the reference axis and the
stringers equals the rotation around the z-reference axis. For
details, please refer to the picture below.
If the reference of the stringer angle shall
be different from the default implementation then this
parameter may be set. Allowed values include: leadingEdge,
trailingEdge and globalY. Furthermore, it is possible to
provide the UID of a spar.
This is the explicit stringer definition.
Please note that for a consistent definition two out of the
possible three elements innerBorder (xsiLE, xsiTE), outerBorder
(xsiLE, xsiTE) and stringer angle (and angle reference) must be
defined. Any combination of two of the three is valid
The number of stringers; default is 0
Stringer angle: the reference axis for the
stringer angle is defined by the two leading edge points of
the 'from'- and the 'to'-element of the componentSegment
definition. The angle between the reference axis and the
stringers equals the rotation around the z-reference axis. For
details, please refer to the picture below.
If the reference of the stringer angle shall
be different from the default implementation then this
parameter may be set. Allowed values include: leadingEdge,
trailingEdge and globalY. Furthermore, it is possible to
provide the UID of a spar.
Inner border xsi coordinate at the leading
edge of the stringer definition
Outer border xsi coordinate at the leading
edge of the stringer definition
Inner border xsi coordinate at the trailing
edge of the stringer definition
Outer border xsi coordinate at the trailing
edge of the stringer definition
wingStructuralMountsType
Wings
Wings type, containing all the lifting surfaces (wings,
HTPs, VTPs, canards...) of an aircraft model.
Wing type, containing all a lifting surface (wing, HTP,
VTP, canard...) of an aircraft model.
Wing type, containing all a lifting surface (wing,
HTP, VTP, canard...) of an aircraft model.
Position of the wing: The position of the wing is
defined using the transformation parameters. Using those
parameters, the wing coordinate system is translated, rotated
and scaled.
Definition of the wings outer shape: The outer shape
of the wing is defined by airfoils that are placed within the 3D
space. Two airfoils are combined to one wing segment within the
segments. For the definition of the positions of the airfoils,
different sections are defined. Within each section one or more
elements are defined. The airfoil shape is defined within the
elements. If the wings outer shape should e.g. have a step it is
possible to define two different airfoils in one section by
using two elements. In most cases each section will only include
one element. Positionings are vectors that are used for an
additional translation of the sections by using 'user friendly
paramaters' as e.g. sweep and dihedral. Please note, the first
positioning may be non-zero. Often it will be zero just to
locate the wing at the position stated by the translation, but
this is not necessary. Finally the wing segments are defined by
combining two consecutive elements. A more detailed description
is given within the different parameters.
Definition of control surfaces, wing structures, wing
fuel tank and wing fuselage attachment: those parts are defined
within componentSegments. Please refer to the documentation
there.
Name of the wing.
Description of the wing.
UID of part to which the wing is mounted (if
any). The parent of the wing can e.g. be the fuselage. In each
aircraft model, there is exactly one part without a parent part
(The root of the connection hierarchy).
The two elements that where the structural connection
is placed.
Element uID of the element of the CURRENT
componentSegment where the structural connection is placed.
Element uID of the element of the second
componentSegment where the structural connection is placed.
Two spars that are structurally connected.
Spar uID of the CURRENT componentSegment.
Spar uID of the second componentSegment.
wingWingAttachmentsSparsType
List of wingWingAttachments.
wingWingAttachmentType
Definition of the structural connection between two
wings resp. two componentSegments. Note: All structural
connections between two wings/componetSegments have to be defined
using wingWingAttachments. The wingWingAttachment has only be
defined in one of the two componentSegments, that are connected.
UID of the componentSegment, that is connected
with the current one.
Defines if the upper shell of the current
componentSegment is structurally connected to the upper or lower
shell of the second componentSegment. Can have the values
'upperShell' or 'lowerShell'.
Defines if the lower shell of the current
componentSegment is structurally connected to the upper or lower
shell of the second componentSegment. Can have the values
'upperShell' or 'lowerShell'.
xsiIsoLineType
Iso line described by point of same xsi coordinate.
Can be either segment or component segment coordinates.
Relative spanwise position. Xsi refers to the segment or componentSegment depending on the referenced uID.
This reference uID determines the reference coordinate system.
If it points to a segment, then the eta value is considered to be in segment
eta coordinate; if it points to a componentSegment,
then componentSegment eta coordinate is used.
zCouplingsType
Definition of one z-coupling.
zCouplingType
Reference to the control surface that is
connected to this control surface by the z-coupling..
Material of the movable part of the
z-coupling.
Definition of the attachment of the z-coupling
to this control surface.
Definition of the attachment of the z-coupling
to the other control surface.