JSBSim Flight Dynamics Model 1.2.2 (22 Mar 2025)
An Open Source Flight Dynamics and Control Software Library in C++
Loading...
Searching...
No Matches
FGAircraft Class Reference

Detailed Description

Encapsulates an Aircraft and its systems.

Owns all the parts (other classes) which make up this aircraft. This includes the Engines, Tanks, Propellers, Nozzles, Aerodynamic and Mass properties, landing gear, etc. These constituent parts may actually run as separate JSBSim models themselves, but the responsibility for initializing them and for retrieving their force and moment contributions falls to FGAircraft.

The <metrics> section of the aircraft configuration file is read here, and the metrical information is held by this class.

Configuration File Format for <metrics> Section:

<metrics>
<wingarea unit="{FT2 | M2}"> {number} </wingarea>
<wingspan unit="{FT | M}"> {number} </wingspan>
<chord unit="{FT | M}"> {number} </chord>
<htailarea unit="{FT2 | M2}"> {number} </htailarea>
<htailarm unit="{FT | M}"> {number} </htailarm>
<vtailarea unit="{FT2 | M}"> {number} </vtailarea>
<vtailarm unit="{FT | M}"> {number} </vtailarm>
<wing_incidence unit="{RAD | DEG}"> {number} </wing_incidence>
<location name="{AERORP | EYEPOINT | VRP}" unit="{IN | M}">
<x> {number} </x>
<y> {number} </y>
<z> {number} </z>
</location>
{other location blocks}
</metrics>
@author Jon S. Berndt
@see Cooke, Zyda, Pratt, and McGhee, "NPSNET: Flight Simulation Dynamic Modeling
 Using Quaternions", Presence, Vol. 1, No. 4, pp. 404-420  Naval Postgraduate
 School, January 1994
@see D. M. Henderson, "Euler Angles, Quaternions, and Transformation Matrices",
 JSC 12960, July 1977
@see Richard E. McFarland, "A Standard Kinematic Model for Flight Simulation at
 NASA-Ames", NASA CR-2497, January 1975
@see Barnes W. McCormick, "Aerodynamics, Aeronautics, and Flight Mechanics",
 Wiley & Sons, 1979 ISBN 0-471-03032-5
@see Bernard Etkin, "Dynamics of Flight, Stability and Control", Wiley & Sons,
 1982 ISBN 0-471-08936-2

Definition at line 102 of file FGAircraft.h.

#include <FGAircraft.h>

+ Inheritance diagram for FGAircraft:
+ Collaboration diagram for FGAircraft:

Classes

struct  Inputs
 

Public Member Functions

 FGAircraft (FGFDMExec *Executive)
 Constructor.
 
 ~FGAircraft () override
 Destructor.
 
const std::string & GetAircraftName (void) const
 Gets the aircraft name.
 
double Getcbar (void) const
 Gets the average wing chord.
 
double GetForces (int idx) const
 
const FGColumnVector3GetForces (void) const
 
double GetHTailArea (void) const
 
double GetHTailArm (void) const
 
double Getlbarh (void) const
 
double Getlbarv (void) const
 
double GetMoments (int idx) const
 
const FGColumnVector3GetMoments (void) const
 
double Getvbarh (void) const
 
double Getvbarv (void) const
 
double GetVTailArea (void) const
 
double GetVTailArm (void) const
 
double GetWingArea (void) const
 Gets the wing area.
 
double GetWingIncidence (void) const
 
double GetWingIncidenceDeg (void) const
 
double GetWingSpan (void) const
 Gets the wing span.
 
double GetXYZep (int idx) const
 
const FGColumnVector3GetXYZep (void) const
 
double GetXYZrp (int idx) const
 
const FGColumnVector3GetXYZrp (void) const
 Gets the the aero reference point (RP) coordinates.
 
double GetXYZvrp (int idx) const
 
const FGColumnVector3GetXYZvrp (void) const
 
bool InitModel (void) override
 
bool Load (Element *el) override
 Loads the aircraft.
 
bool Run (bool Holding) override
 Runs the Aircraft model; called by the Executive Can pass in a value indicating if the executive is directing the simulation to Hold.
 
void SetAircraftName (const std::string &name)
 
void SetWingArea (double S)
 
void SetXYZrp (int idx, double value)
 
- Public Member Functions inherited from FGModel
 FGModel (FGFDMExec *)
 Constructor.
 
 ~FGModel () override
 Destructor.
 
virtual SGPath FindFullPathName (const SGPath &path) const
 
FGFDMExecGetExec (void)
 
const std::string & GetName (void)
 
unsigned int GetRate (void)
 Get the output rate for the model in frames.
 
bool InitModel (void) override
 
void SetPropertyManager (std::shared_ptr< FGPropertyManager > fgpm)
 
void SetRate (unsigned int tt)
 Set the ouput rate for the model in frames.
 
- Public Member Functions inherited from FGModelFunctions
std::string GetFunctionStrings (const std::string &delimeter) const
 Gets the strings for the current set of functions.
 
std::string GetFunctionValues (const std::string &delimeter) const
 Gets the function values.
 
std::shared_ptr< FGFunctionGetPreFunction (const std::string &name)
 Get one of the "pre" function.
 
bool Load (Element *el, FGFDMExec *fdmex, std::string prefix="")
 
void PostLoad (Element *el, FGFDMExec *fdmex, std::string prefix="")
 
void PreLoad (Element *el, FGFDMExec *fdmex, std::string prefix="")
 
void RunPostFunctions (void)
 
void RunPreFunctions (void)
 
- Public Member Functions inherited from FGJSBBase
 FGJSBBase ()
 Constructor for FGJSBBase.
 
virtual ~FGJSBBase ()
 Destructor for FGJSBBase.
 
void disableHighLighting (void)
 Disables highlighting in the console output.
 

Public Attributes

struct JSBSim::FGAircraft::Inputs in
 

Additional Inherited Members

- Public Types inherited from FGJSBBase
enum  { eL = 1 , eM , eN }
 Moments L, M, N. More...
 
enum  { eP = 1 , eQ , eR }
 Rates P, Q, R. More...
 
enum  { eU = 1 , eV , eW }
 Velocities U, V, W. More...
 
enum  { eX = 1 , eY , eZ }
 Positions X, Y, Z. More...
 
enum  { ePhi = 1 , eTht , ePsi }
 Euler angles Phi, Theta, Psi. More...
 
enum  { eDrag = 1 , eSide , eLift }
 Stability axis forces, Drag, Side force, Lift. More...
 
enum  { eRoll = 1 , ePitch , eYaw }
 Local frame orientation Roll, Pitch, Yaw. More...
 
enum  { eNorth = 1 , eEast , eDown }
 Local frame position North, East, Down. More...
 
enum  { eLat = 1 , eLong , eRad }
 Locations Radius, Latitude, Longitude. More...
 
enum  {
  inNone = 0 , inDegrees , inRadians , inMeters ,
  inFeet
}
 Conversion specifiers. More...
 
- Static Public Member Functions inherited from FGJSBBase
static const std::string & GetVersion (void)
 Returns the version number of JSBSim.
 
static constexpr double KelvinToFahrenheit (double kelvin)
 Converts from degrees Kelvin to degrees Fahrenheit.
 
static constexpr double CelsiusToRankine (double celsius)
 Converts from degrees Celsius to degrees Rankine.
 
static constexpr double RankineToCelsius (double rankine)
 Converts from degrees Rankine to degrees Celsius.
 
static constexpr double KelvinToRankine (double kelvin)
 Converts from degrees Kelvin to degrees Rankine.
 
static constexpr double RankineToKelvin (double rankine)
 Converts from degrees Rankine to degrees Kelvin.
 
static constexpr double FahrenheitToCelsius (double fahrenheit)
 Converts from degrees Fahrenheit to degrees Celsius.
 
static constexpr double CelsiusToFahrenheit (double celsius)
 Converts from degrees Celsius to degrees Fahrenheit.
 
static constexpr double CelsiusToKelvin (double celsius)
 Converts from degrees Celsius to degrees Kelvin.
 
static constexpr double KelvinToCelsius (double kelvin)
 Converts from degrees Kelvin to degrees Celsius.
 
static constexpr double FeetToMeters (double measure)
 Converts from feet to meters.
 
static bool EqualToRoundoff (double a, double b)
 Finite precision comparison.
 
static bool EqualToRoundoff (float a, float b)
 Finite precision comparison.
 
static bool EqualToRoundoff (float a, double b)
 Finite precision comparison.
 
static bool EqualToRoundoff (double a, float b)
 Finite precision comparison.
 
static constexpr double Constrain (double min, double value, double max)
 Constrain a value between a minimum and a maximum value.
 
static constexpr double sign (double num)
 
- Static Public Attributes inherited from FGJSBBase
static char highint [5] = {27, '[', '1', 'm', '\0' }
 highlights text
 
static char halfint [5] = {27, '[', '2', 'm', '\0' }
 low intensity text
 
static char normint [6] = {27, '[', '2', '2', 'm', '\0' }
 normal intensity text
 
static char reset [5] = {27, '[', '0', 'm', '\0' }
 resets text properties
 
static char underon [5] = {27, '[', '4', 'm', '\0' }
 underlines text
 
static char underoff [6] = {27, '[', '2', '4', 'm', '\0' }
 underline off
 
static char fgblue [6] = {27, '[', '3', '4', 'm', '\0' }
 blue text
 
static char fgcyan [6] = {27, '[', '3', '6', 'm', '\0' }
 cyan text
 
static char fgred [6] = {27, '[', '3', '1', 'm', '\0' }
 red text
 
static char fggreen [6] = {27, '[', '3', '2', 'm', '\0' }
 green text
 
static char fgdef [6] = {27, '[', '3', '9', 'm', '\0' }
 default text
 
static short debug_lvl = 1
 
- Protected Member Functions inherited from FGModel
bool Upload (Element *el, bool preLoad)
 Uploads this model in memory.
 
- Static Protected Member Functions inherited from FGJSBBase
static std::string CreateIndexedPropertyName (const std::string &Property, int index)
 
- Protected Attributes inherited from FGModel
unsigned int exe_ctr
 
FGFDMExecFDMExec
 
std::string Name
 
std::shared_ptr< FGPropertyManagerPropertyManager
 
unsigned int rate
 
- Protected Attributes inherited from FGModelFunctions
FGPropertyReader LocalProperties
 
std::vector< std::shared_ptr< FGFunction > > PostFunctions
 
std::vector< std::shared_ptr< FGFunction > > PreFunctions
 
- Static Protected Attributes inherited from FGJSBBase
static constexpr double radtodeg = 180. / M_PI
 
static constexpr double degtorad = M_PI / 180.
 
static constexpr double hptoftlbssec = 550.0
 
static constexpr double psftoinhg = 0.014138
 
static constexpr double psftopa = 47.88
 
static constexpr double fttom = 0.3048
 
static constexpr double ktstofps = 1852./(3600*fttom)
 
static constexpr double fpstokts = 1.0 / ktstofps
 
static constexpr double inchtoft = 1.0/12.0
 
static constexpr double m3toft3 = 1.0/(fttom*fttom*fttom)
 
static constexpr double in3tom3 = inchtoft*inchtoft*inchtoft/m3toft3
 
static constexpr double inhgtopa = 3386.38
 
static constexpr double slugtolb = 32.174049
 Note that definition of lbtoslug by the inverse of slugtolb and not to a different constant you can also get from some tables will make lbtoslug*slugtolb == 1 up to the magnitude of roundoff.
 
static constexpr double lbtoslug = 1.0/slugtolb
 
static constexpr double kgtolb = 2.20462
 
static constexpr double kgtoslug = 0.06852168
 
static const std::string needed_cfg_version = "2.0"
 
static const std::string JSBSim_version = JSBSIM_VERSION " " __DATE__ " " __TIME__
 

Constructor & Destructor Documentation

◆ FGAircraft()

FGAircraft ( FGFDMExec Executive)

Constructor.

Parameters
Executivea pointer to the parent executive object

Definition at line 52 of file FGAircraft.cpp.

52 : FGModel(fdmex)
53{
54 Name = "FGAircraft";
55 WingSpan = 0.0;
56 WingArea = 0.0;
57 cbar = 0.0;
58 HTailArea = VTailArea = 0.0;
59 HTailArm = VTailArm = 0.0;
60 lbarh = lbarv = 0.0;
61 vbarh = vbarv = 0.0;
62 WingIncidence = 0.0;
63
64 bind();
65
66 Debug(0);
67}
FGModel(FGFDMExec *)
Constructor.
Definition FGModel.cpp:57

◆ ~FGAircraft()

~FGAircraft ( )
override

Destructor.

Definition at line 71 of file FGAircraft.cpp.

72{
73 Debug(1);
74}

Member Function Documentation

◆ GetAircraftName()

const std::string & GetAircraftName ( void  ) const
inline

Gets the aircraft name.

Returns
the name of the aircraft as a string type

Definition at line 131 of file FGAircraft.h.

131{ return AircraftName; }
+ Here is the caller graph for this function:

◆ Getcbar()

double Getcbar ( void  ) const
inline

Gets the average wing chord.

Definition at line 138 of file FGAircraft.h.

138{ return cbar; }

◆ GetForces() [1/2]

double GetForces ( int  idx) const
inline

Definition at line 152 of file FGAircraft.h.

152{ return vForces(idx); }

◆ GetForces() [2/2]

const FGColumnVector3 & GetForces ( void  ) const
inline

Definition at line 151 of file FGAircraft.h.

151{ return vForces; }

◆ GetHTailArea()

double GetHTailArea ( void  ) const
inline

Definition at line 141 of file FGAircraft.h.

141{ return HTailArea; }

◆ GetHTailArm()

double GetHTailArm ( void  ) const
inline

Definition at line 142 of file FGAircraft.h.

142{ return HTailArm; }

◆ Getlbarh()

double Getlbarh ( void  ) const
inline

Definition at line 145 of file FGAircraft.h.

145{ return lbarh; } // HTailArm / cbar

◆ Getlbarv()

double Getlbarv ( void  ) const
inline

Definition at line 146 of file FGAircraft.h.

146{ return lbarv; } // VTailArm / cbar

◆ GetMoments() [1/2]

double GetMoments ( int  idx) const
inline

Definition at line 150 of file FGAircraft.h.

150{ return vMoments(idx); }

◆ GetMoments() [2/2]

const FGColumnVector3 & GetMoments ( void  ) const
inline

Definition at line 149 of file FGAircraft.h.

149{ return vMoments; }

◆ Getvbarh()

double Getvbarh ( void  ) const
inline

Definition at line 147 of file FGAircraft.h.

147{ return vbarh; } // H. Tail Volume

◆ Getvbarv()

double Getvbarv ( void  ) const
inline

Definition at line 148 of file FGAircraft.h.

148{ return vbarv; } // V. Tail Volume

◆ GetVTailArea()

double GetVTailArea ( void  ) const
inline

Definition at line 143 of file FGAircraft.h.

143{ return VTailArea; }

◆ GetVTailArm()

double GetVTailArm ( void  ) const
inline

Definition at line 144 of file FGAircraft.h.

144{ return VTailArm; }

◆ GetWingArea()

double GetWingArea ( void  ) const
inline

Gets the wing area.

Definition at line 134 of file FGAircraft.h.

134{ return WingArea; }

◆ GetWingIncidence()

double GetWingIncidence ( void  ) const
inline

Definition at line 139 of file FGAircraft.h.

139{ return WingIncidence; }

◆ GetWingIncidenceDeg()

double GetWingIncidenceDeg ( void  ) const
inline

Definition at line 140 of file FGAircraft.h.

140{ return WingIncidence*radtodeg; }

◆ GetWingSpan()

double GetWingSpan ( void  ) const
inline

Gets the wing span.

Definition at line 136 of file FGAircraft.h.

136{ return WingSpan; }

◆ GetXYZep() [1/2]

double GetXYZep ( int  idx) const
inline

Definition at line 160 of file FGAircraft.h.

160{ return vXYZep(idx); }

◆ GetXYZep() [2/2]

const FGColumnVector3 & GetXYZep ( void  ) const
inline

Definition at line 157 of file FGAircraft.h.

157{ return vXYZep; }

◆ GetXYZrp() [1/2]

double GetXYZrp ( int  idx) const
inline

Definition at line 158 of file FGAircraft.h.

158{ return vXYZrp(idx); }

◆ GetXYZrp() [2/2]

const FGColumnVector3 & GetXYZrp ( void  ) const
inline

Gets the the aero reference point (RP) coordinates.

Returns
a vector containing the RP coordinates in the structural frame.

Definition at line 155 of file FGAircraft.h.

155{ return vXYZrp; }

◆ GetXYZvrp() [1/2]

double GetXYZvrp ( int  idx) const
inline

Definition at line 159 of file FGAircraft.h.

159{ return vXYZvrp(idx); }

◆ GetXYZvrp() [2/2]

const FGColumnVector3 & GetXYZvrp ( void  ) const
inline

Definition at line 156 of file FGAircraft.h.

156{ return vXYZvrp; }

◆ InitModel()

bool InitModel ( void  )
overridevirtual

Reimplemented from FGModelFunctions.

Definition at line 78 of file FGAircraft.cpp.

79{
80 if (!FGModel::InitModel()) return false;
81
82 vForces.InitMatrix();
83 vMoments.InitMatrix();
84
85 return true;
86}

◆ Load()

bool Load ( Element el)
overridevirtual

Loads the aircraft.

The executive calls this method to load the aircraft into JSBSim.

Parameters
ela pointer to the element tree
Returns
true if successful

Reimplemented from FGModel.

Definition at line 116 of file FGAircraft.cpp.

117{
118 string element_name;
119 Element* element;
120
121 if (!FGModel::Upload(el, true)) return false;
122
123 if (el->FindElement("wingarea"))
124 WingArea = el->FindElementValueAsNumberConvertTo("wingarea", "FT2");
125 if (el->FindElement("wingspan"))
126 WingSpan = el->FindElementValueAsNumberConvertTo("wingspan", "FT");
127 if (el->FindElement("chord"))
128 cbar = el->FindElementValueAsNumberConvertTo("chord", "FT");
129 if (el->FindElement("wing_incidence"))
130 WingIncidence = el->FindElementValueAsNumberConvertTo("wing_incidence", "RAD");
131 if (el->FindElement("htailarea"))
132 HTailArea = el->FindElementValueAsNumberConvertTo("htailarea", "FT2");
133 if (el->FindElement("htailarm"))
134 HTailArm = el->FindElementValueAsNumberConvertTo("htailarm", "FT");
135 if (el->FindElement("vtailarea"))
136 VTailArea = el->FindElementValueAsNumberConvertTo("vtailarea", "FT2");
137 if (el->FindElement("vtailarm"))
138 VTailArm = el->FindElementValueAsNumberConvertTo("vtailarm", "FT");
139
140 // Find all LOCATION elements that descend from this METRICS branch of the
141 // config file. This would be CG location, eyepoint, etc.
142
143 element = el->FindElement("location");
144 while (element) {
145 element_name = element->GetAttributeValue("name");
146
147 if (element_name == "AERORP") vXYZrp = element->FindElementTripletConvertTo("IN");
148 else if (element_name == "EYEPOINT") vXYZep = element->FindElementTripletConvertTo("IN");
149 else if (element_name == "VRP") vXYZvrp = element->FindElementTripletConvertTo("IN");
150
151 element = el->FindNextElement("location");
152 }
153
154 // calculate some derived parameters
155 if (cbar != 0.0) {
156 lbarh = HTailArm/cbar;
157 lbarv = VTailArm/cbar;
158 if (WingArea != 0.0) {
159 vbarh = HTailArm*HTailArea / (cbar*WingArea);
160 vbarv = VTailArm*VTailArea / (WingSpan*WingArea);
161 }
162 }
163
164 PostLoad(el, FDMExec);
165
166 Debug(2);
167
168 return true;
169}
bool Upload(Element *el, bool preLoad)
Uploads this model in memory.
Definition FGModel.cpp:110
+ Here is the call graph for this function:

◆ Run()

bool Run ( bool  Holding)
overridevirtual

Runs the Aircraft model; called by the Executive Can pass in a value indicating if the executive is directing the simulation to Hold.

Parameters
Holdingif true, the executive has been directed to hold the sim from advancing time. Some models may ignore this flag, such as the Input model, which may need to be active to listen on a socket for the "Resume" command to be given.
See also
JSBSim.cpp documentation
Returns
false if no error

Reimplemented from FGModel.

Definition at line 90 of file FGAircraft.cpp.

91{
92 if (FGModel::Run(Holding)) return true;
93 if (Holding) return false;
94
95 RunPreFunctions();
96
97 vForces = in.AeroForce;
98 vForces += in.PropForce;
99 vForces += in.GroundForce;
100 vForces += in.ExternalForce;
101 vForces += in.BuoyantForce;
102
103 vMoments = in.AeroMoment;
104 vMoments += in.PropMoment;
105 vMoments += in.GroundMoment;
106 vMoments += in.ExternalMoment;
107 vMoments += in.BuoyantMoment;
108
109 RunPostFunctions();
110
111 return false;
112}
virtual bool Run(bool Holding)
Runs the model; called by the Executive.
Definition FGModel.cpp:89
+ Here is the call graph for this function:

◆ SetAircraftName()

void SetAircraftName ( const std::string &  name)
inline

Definition at line 161 of file FGAircraft.h.

161{AircraftName = name;}

◆ SetWingArea()

void SetWingArea ( double  S)
inline

Definition at line 165 of file FGAircraft.h.

165{WingArea = S;}

◆ SetXYZrp()

void SetXYZrp ( int  idx,
double  value 
)
inline

Definition at line 163 of file FGAircraft.h.

163{vXYZrp(idx) = value;}

The documentation for this class was generated from the following files: