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A SET OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT SIMULATION. CU) UNdLASSIF IED ARL IAEROTMTM-339NL UI fl**ff***

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Page 1: OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT ...The various options are discussed by Etkin [2i and other authors, such as Fogarty and Howe [31, and McFarland 15). 3.1 Force Equations In

A SET OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT SIMULATION. CU)

UNdLASSIF IED ARL IAEROTMTM-339NL

UIfl**ff***

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AM-ASTID0-T~tlU-N0-339 AR-002-888

DEPARTMENT OF DEFENCE SUPPORT

DEFENCE SCIENCE AND TECHNOLOGY ORGANISATION

AERONAUTICAL RESEARCH LABORATORIES

MELBOURNE. VICTORIA

Aerodynamics Technical Memorandum 339

A SET OF FLIGHT DYNAMIC EQUATIOiS FORAIRCRAFT SIMULATION

P. H. HAWL

Approved for Public Release -

'Lie tenant P.H. Hall ia an officer of the

RAN and is an attacrent to ARL.- - 4J

(C) COMUOSW3I' OF AUSTRA61A 1982

CO" N 82 09 24 070 J N, 1962

UNCLASSIFIED

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AR-002-888

DEPART MT OF DEFENCE SUPPORT

DEFENCE SCIENCE AND TECHNOLOGY ORGANISATO.

AERONAUTICAL RESEARCH LABORATORIES

Aerodynamics Technicl Memorandum 339

A SET OF FLIGHT DYNAMIC EQUATIONS FORAIRCRAFT SI MIU LAT 0 ION

Jy

P. H. FALL* XC4

SYMAPY

The six degrees of freedom dynamic equations ofaircraft motion have been documented in this Memorandum foruse in aircraft simulations at ARL. Earth axes are chosenfor the integration of the force quations, and body axes for

the integration of the moment equations. The use of quaternionsto calculate aircraft altitude and associated direction cosinesis described. This Memorandum also contains a brief descriptionof an atomsphezic data subroutine for use in aircraft simulation.

O CCMO*4 VALTl OF AUSTRALIA

POSTAL ADDRESS: Chief Superintendent, Aeronautical Research La ratoris,P.O. Box 4331, Melbourne, Victoria, 3001, Australia.

* Lieutenant P.H. Hall, RAN is on attachment to ARL.

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CONTENTS

PAGE NO.

1. INTRODUCTION 1

2. DEFINITION OF AXES SYSTEMS USED IN THE SET OF 1

EQUATIONS

2.1 Earth Axes 1

2.2 Body Axes 2

2.3 Stability Axes 2

2.4 Air-path Axes 2

3. SELECTION OF AXES FOR INTEGRATION OF EQUATIONS 2

3.1 Force Equations 2

3.2 Moment Equations 3

4. AIRCRAFT ATTITUDE DETERMINATION 3

5. AXES TRANSFORMATION 5

6. EQUATIONS OF MOTION 5

6.1 Force Equations 5

6.2 Moment Equations 8

7. ATMOSPHERIC DATA 9

8. CONCLUSION 10

REFERENCES

NOTATION

FIGURES 1 & 2

DISTRIBUTION LIST

DOCUMMNT CONTROL DATA Fo__

"1IS C3mjest , .t l

fDricN ,*giIola/-.

M OPCE god/or¢ 2 91i% 1 ~~a

Dis

L.

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-- "

1. INTRODUCTION

In August 1981, a research program was initiated at ARL,under Royal Australian Navy sponsorship, to study the dynamicbehaviour of V/STOL aircraft. The study will be based on a sixdegrees of freedom simulation of a military jet V/STOL aircraft,programed using the Advanced Continuous Simulation Language (ACSL)*on the ARL DEC System-10 computer.

Important aspects of the simulation are the derivation ofthe basic dynamic equations of aircraft motion, and the selectionof suitable reference axes systems. Based on current practice,earth axes were chosen for the integration of the force equations,and body axes for the integration of the moment equations. Inaddition, the quaternion parameters were chosen for the calculationof the Euler angles.

This Memorandum provides a documentation of the basic sixdegrees of freedom dynamic equations of motion for ise in aircraftsimulations. The axes systems used in the set of equations aredefined in section 2, while section 3 discusses the selection ofaxes systems for integration. The use of quaternions in determiningaircraft attitude and performing axes transformations is dealt within sections 4 and 5 respectively. The equations of motion arederived and listed in section 6, and summarized in figure 2. Section7 provides a brief note on the source of atmospheric data and liststhe atmospheric models which have been incorporated.

2. DEFINITION OF AXES SYSTEMS USED IN THE SET OF EQUATIONS

All axes systems are assumed to be orthogonal, right-handed triads, and are shown in figure 1.

2.1 Earth Axes (X ,Y ,ZE)

The origin is at a point fixed on the earth's surface,typically at the runway threshold and on the centreline (Rt,.The X-axis points North; the Y-axis East; and the Z-axis laown,toward the centre of the earth. It is assumed that the earth isflat and non-rotating, such that the earth axes are regarded as aninertial frame.

* Mitchell & Gauthier Associates, Inc.

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2.2 (XBDYB'ZB

Body axes are fixed on the aircraft with the origin locatedat the aircraft centre of qravity. The aircraft is assumed teo berigid, with the X-axis parallel to the horizontal fuselage referenceline and pointing 'forward'; the Y-axis pointing to starboard (right);aand the Z-axis 'downward'.

2.3 Stability Axes (X S Y S Z

Stability axes are a special set of body axes used primarilyin the study of small disturbances from a steady reference flightcondition. Aerodynamic data are frequently presented in stabilityaxes. These axes are displaced from the body frame by the angle ofattack, a, such that the X-axis in the steady-state is aligned withthe projection of the relative wind vector on the aircraft planeof symmetry; the Yi-axis points to starboard; and the Z-axis'downward'.

2.4 Air-Path Axes (X W Y W Zd

Air-path axes differ from body axes by the angle of attack,a, and the angle of sideslip, B. The transformation from body to

throuqh -a, to coincide with the stability axes, and then yawingthrough B. The origin is located at the aircraft centre of gravityand the X-axis is aligned with the relative wind vector.

Note- When the wind velocity components are zero, the air-pathaxes coincide with the flight-path axes as defined by Fogarty andHowe (3]. Etkin [2) refers to the air-path axes as the air-trajectoryreference frame (or wind axes).

3. SELECTION4 OF AXES FOR INTEGRATION OF EQUATIONS

There are qood reasons to use mixed axes systems whenstudying the many measurements and observations of vehicle motion.The various options are discussed by Etkin [2i and other authors,such as Fogarty and Howe [31, and McFarland 15).

3.1 Force Equations

In recent years there has been a trend away from the useof body axes fox tintt computation and integration of force equations.Flight-path axes do have definite benefits in terms of computerscaling and computation speed (31. However, where these factorsare not of over-ridinq importance, the selection of earth axes isbecoming quite common.

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For the proposed V/STOL aircraft studies, the earth axessystem was selected for the computation and integration of thetranslational equations of motion for the following reasons:

(i) it gives commonality with the axes system chosen by both

RAE Bedford and NASA Ames in their simulation programs(1,5];

(ii) it is the logical choice for modelling an aircraft operatingfrom a moving ship, since there is a need to refer theforces and motion of both vehicles to a common referenceframe; and

(iii) it avoids the complications which exists with other axessystems when considering the presence of winds andturbulence, as hiqhlighted by McFarland [5].

3.2 Moment Equations

The body axes system is the natural choice for the solutionof the rotational equations of motion because of the importantadvantage of constant moments of inertia when calculating themoments and angular motion of the aircraft.

4. AIRCRAFT ATTITUDE DETERMINATION

The attitude of an aircraft is defined in terms of thetraditional Euler angles, * (heading angle), e (pitch attitude),and * (roll, or 'bank' angle). In order to avoid the problemsassociated with the singularity in the Euler 'rate' equations,which occurs when 8=±90 °, quaternion components [71 or directioncosines may be used in the integration step.

Quaternion components were chosen for the followingreasons:

(i) their time derivatives are always finite and continuous,

whereas those of the Euler angles possess singularities;

(ii) the computations remain accurate as e approaches 90°;

(iii) it is a four narameter method consisting of four integrationswith one constraint equation, whereas direction cosines,in principlv, zetquire nine integrations and six constraintequations.

The quaternion components are expressible in terms of Eulerangles as follows:

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To = cos$/2 cos8/2 cos*/2 + sinf/2 sine/2 sin*/2

= sin/2 cose/2 cos /2 - cosO/2 sine/2 sin/2

T2 = coso/2 sine/2 cos*/2 + sin*/2 cos6/2 sin/2

3 = cosf/2 cos8/2 sin*/2 - sin/2 sine/2 cosu/2

The quaternion component time derivatives are given by,

0 - 1/2 (PT1 + QT 2 + RT 3)

= a 1/2 (P 0 - Q 3 + RT2 )

0 3(2)

2 = 1/2 (PT3 + QT0 - RT1 )

f - 1/2 (Pr2 - PT 1 - RT0 )

where P,Q,R are angular velocity components about body axes, and

'02 + TIa + T22 + T32 = 1 (3)

Failure to normalize the quaternion components at each iteration canresult ir the integration becoming unstable.

Euler angles may be derived from the quaternion componentsby using the following relationships,

t-1 I 2 T3 1 0otIr a -1 3 (4)

9 = tan - 0 2 TT3 tan L3

U a I(Tor 2-1/2) 2+(T 1 T 2+T 127 (L 3 a113 ' 1/2'(5)

-=a-,[ 1T l+ TOT3 - tan-, [L 2 (6)

The initial Euler angles are used to determine the initial

quaternion components, which are in turn used to calculate the directioncosine parameters for use in axes transformation computations. Thequaternion components are updated at each iteration, using equation

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(2), such that the direction cosines are recalculated for use inthe equations of motion, while the Euler angles are calculated ascutput data only.

5. AXES TRANSFORMATION

Transformation of a set of variables from body axes toearth axes (or vice-versa) is conveniently achieved by use of directioncosines (6], which are obtained in terms of the quaternion componentsby the following relationships,

L1 02 (T0 + T12)1

L2 = 2(T1T2 + T0T3

L = 2 (IT3 T 0T2)

14 = 2 (TI1 - TOT 3

M = 2 (T0 2 + T2 ) -1 (7)

3 = 2 (T 3 + TOT I1

N1 2 (c1T3 I OT2)

N =2 (N2 =2 3

N3 2 02 + T 32)

6. EQUATIONS OF MOTION

Figure 2 is a summary of the overall six degrees of freedomdynamic equations for the case of a flat earth.

6.1 Force Equatione

The aerodynamic force components are frequently computedalong stability axes, and the propulsive force components are usuallysupplied in body axes. The resolutes along stability axes are:

F XS X? cosa + Z sina + XA

F YP + YA (8)

F Zp cosa- X sina + ZA

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The total force components in earth axes are obtained bythe transformation of the forces in stability axes, using directioncosines, and the addition of the gravitational force component, asshown by equation (9). 'g' is assumed constant such that thecalculated altitude in figure 2 is the geopotential height, as usedin standard atmosphere calculations.

F " (LCosa + 1,sina) F + IsF + (NCosa - Llsina) FXE I XS 1lYS 1 1z

FyE 0 (L2cosa + 1,2sin) FXS + M2FYS + (N2Csa - L2sina) FZS (9)

FZE w (L3cosa + N3sina) FXS + M3F + (N3cosa - L3sina) FZS + W

The components of acceleration with respect to the earthare obtained simply from the dynamic equations:

VE = F E/m

V'E F YE/M (10)

DE= FZE/mDE FZE /

where r is the aircraft mass, and virtual mass effects are ignored.

The velocity components of the aircraft relative to theearth are obtained from the direct integration of equation (10).The components of the wind velocity relative to the ground are thenadded, giving the velocity components of the aircraft relative tothe air mass;

vE = VE - VWE(VN NE VWN

V E V EE v WVD V DE - WD

The components of the aircraft velocity vector relative tothe air, in body axes, are derived using equations (7) and (11),as shown by equation (12).

UB (L VN) + (L2 VE ) + (L VD

V = (M V) + (M V) + (M V) (12)B 1N 2 E 3 D

w = (NI V N + (N2 VL + (3 V )

B N2E3

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The resultant velocity (or True Airspeed) of the aircraftis then:

VTAS = (U B + V B2 + B2)1/2 (13)

The angles of attack, a, and sideslip, 0, are alsodetermined using equations (12) to (15);

a = tan- I U B/UBI in the range ±1800 (14)

8 = tan1'[ V,/(Ua + WB2)l12; in the range ±900 (15)

or = si [vB/vTAs ] (16)

Time derivatives of these angles are reouired in theaerodynamic force and moment calculations. Adequate estimates canbe obtained from polynomial fits to the current values and thosefrom a few preceeding time steps. Tomlinson [8] uses a quadratic fitto estimate 6 and 8.

e.g. a(t) aft-2ft) - 4a(t-ft) + 3a(t) (17)2At

Plight-.path parameters are derived directly from the earthaxes velocity vector components using equations (18) to (20):

Ground speed, 1/2V = (VE 2 + 2E~) (18)

VC-R EE

Flight-path angle,

y tan 1 LvDE/VGRI (19)

Angle of track, east of north

X = tan- IvEr/VrE1 (20)

The positional coordinates of the aircraft's centre ofgravity are derived by intectrating the earth axes velocity vectorcomp.onents:

Distance travelled North,

=VNE (21)

Distance travelled East,

V = EE (22)

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Altitude,

ALT = -VDE (23)

The additional parameter of aircraft range is calculatedusing the definition:

G = (xa + yZ) I/2 (24)

Linear accelerations at the aircraft's centre of gravity(in units of 'g'), are calculated by transforming the linearaccelerations in earth axes (enuation (10)) to body axes, usingequation (7), and dividing by 'g'. Linear accelerations at thepilot's head and elsewhere (e.g. for accelerometers) can then bederived as required by the user.

6.2 Moment Equations

The total moments acting on an aircraft consist of aerodynamic and powerplant components. The powerplant components whiinclude gyroscopic moments due to powerplant rotors, and thrustalignment moments, are normally given in body axes. The aerodynamicmoments are, like the aerodynamic forces, frequently given in stabilityaxes [3]. If the aerodynamic moments are given in body axes, thesimplification of equation (25) is obvious (i.e. set a=O).

L = LA cosa - A sine + Lp

M = N A+ ip (25)

N = LA sine + 'A cosc + NP

If it is assumed that the aircraft has a plane of symmetry,such that the products of inertia I and I are zero, then the bodyaxes angular accelerations can be caiculategyby using equation (26).

= L.C + I..C 2 + (P.C3 + R.C I ) Q

Q .C5 + (R2-P2) C. + R.P.C 7 (26)

= 8 + L.C2 + (P.c 9 - R.C3) Q

where

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CO = IXX I - I X ,

C = Iz/C 0

C = I /C2 XZ 0

C 3 = C2 (1 X- Iyy + ZZ

C = CI (I - I ZZ) - C1XZ

4 1 YY Z XC5 = 1/Iy

C6 = 51XZ

C 7 C5 (I - IXX

5, I z XX Ccs = Ix/C0

C9 = C (Ix -* Xy) +C2IC9 C6 (1XX IYY C2 1X7

The constants C to C9 are evaluated durinq initialization.

The aircraft angular velocity components may then beobtained by interrating equation (26).

7. ATHOSPHERIC DATA

Aribient atmos-heric temperature (Tamb), pressure (Pamb),and density (p), are obtained as a function of altitude from asubroutine version of the proiram ATMOS.PHH.

ATMOS.PHH calculates the variation of atmospheric pLopertieswith altitude and has an altitude range from zero to 100,000 feet.There are six options available to the user; selection being madeby setting the flag "KEYAIR" in accordance with Table 1.

ATi4OS.PHH can be easily modified to calculate temperature/pressure/density ratios, Mach number and speed of sound if required.The criteria required to calculate the ARDU Tropical Atmosphere arethose pres 2nted by Kipp (41.

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TABLE 1:AT1 OSPHERZ OPTIONS OF AT OS.PHH

KEYAIR ATrISPHERE DATA REQUIRED

l(default) ICAO Standard Atmosphere ALT

2 ICAO Sea Level conditions at

all tires

3 Off-Standard ICAO ALT,TDAY,QNH,HAFR

4 ARDU Tropical Atmosphere ALT

5 ARDU Sea Level conditions at

all tires

6 Off-Standard ARDU ALT,TDAY,QNH,HAFR

8. CONCLUSION

The basic six degrees of freedort dynamic equations ofaircraft motion have been locumented in this ]ierorandum for use inaircraft simulations at ARL. The earth axes system was selected forthe integration of the force equations, and the body axes system forthe integration of the rorent equations. Ouaternion components havebeen used to calculate Euler angles and direction cosines. A routinefor calculating atmospheric variables has been provided.

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REFERENCES

1. Cooke, R.A. "Standard Sets of Axes, Units and Identifiers forUse in the Software for the RAE Air CombatSimulator.RAE TM FS-307, January 1980

2. Etkin, B. "Dynamics of Atmospheric Flight".Wiley, 1972

3. Fogarty, L.E. and Howe, R.M. 'Computer mechanization ofSix-Degree of Freedom Flight Equations".NASA CR-1344, May 1969

4. Kipp, G.W. "A Computer Program to Produce Atmospheric Datafor Aircraft Performance Calculations'.ARL/ME TM-367, April 1975

5. McFarland, R.E. "A Standard Kinematic Model for FlightSimulation at NASA-Ames".NASA CR-2497, January 1975

6. Potter, J.E-, Stern, R.G., Smith, T.B. and Sinha, P. "DigitalFlight Control Research".NASA CR-2433, August 1974

7. Robinson, A.C. "On the Use of Quaternions in Simulation ofRigid-Body Motion".WADC TR 58-17, December 1958

8. Tomlinson, B.N. "SESAME - A System of Equations for theSimulation of Aircraft in a Modular Environment".RAE TR-79008, January 1979

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NOTATION

ALT altitude (ft, m)

C. (i,9) inertia constants

Fx,F ,F applied forces in earth axes (Ibf, N)XEYE ZE

Fx,F ,F applie,! forces in stability axes (lbf, N)XS' Ys' zSg gravitational constant (32.174 ft/s2 , 9.81 m/s)

HAPR height of the airfield reference point aboveMSL (ft, m)

IXX ,I yyIzIxz moments and product of inertia (lb ft2 , Kg m2)

KEYAIR flag to select desired atmosphere in ATMOS.PHH

L,M,N total roments (ft-lbf, N-m)

LAMA,'A aerodynamic moments (ft-lbf, N-m)

Lp ,Mp ,pI powerplant moments (ft-lbf, N-m)

Li,MiN i (i=1,3) direction cosines

MSL mean sea level

m aircraft mass (lb, Kg)

Pamb ambient atmospheric pressure (Ibf/fta, N/m)

P,Q,R angular velocity components about body axes(rad/s)

QNH airfield pressure altitude above I.SL (millibars)

RG aircraft range (ft, m)RTt centreline of runway threshold

Tamb ambient atmospheric temperature (C)

TDAY ambient air temperature at airfield referencepoint (C)

UBVBB body axes velocity components (ft/s, m/s)

VGR aircraft around speed (ft/s, m/s)

VNVEVD comnonents of airsneed in earth axes (north,east, down) (ft/s, m/s)

V,VEE,VE components of velocity relative to earth(ft/s, m/s)

VTAS true airspeed (ft/s, m/s)

VT,VE," V components of total wind velocity relative toearth (ft/s, m/s)

W aircraft weiqht i.e. W = mg (lbf, N)

.../cont.

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NOTATION (CONT.)

XA,YA,ZA aerodynamic forces (drag, sideforce, lift)(bf, r)

XB B B body axes reference frame

XE YE ZE earth axes reference frame

X p,Y ,z p propulsive forces (lbf, :)

XsY S stability axes reference frame

XI,YWZw air-path axes reference frame

x,y positional coordinates (ft, m)

aangle of attack (rad.)

angle of sideslip (rad.)

Y flight-path angle, or 'angle of climb' (rad.)

" ,6er 6 control surface deflections: aileron, elevatorrudder (rad.)

Euler angles of pitch, roll (bank) and yaw(heading) (rad.)

P air density (lb/ft3 , Kg/m3)

r. (i=0,3) quaternion components1

X angle of track, east of north (rad.)

Subscripts

amb ambient

A aerodynamic contribution

B body axes

E earth axes

P powerplant contribution

S stability axes

W air-path axes

7NI E WD North, East and Downwards wind velocity

A dot over a variable denotes the first derivative with respect totime.

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LAU4

xx4h 4I

a LL

LU0

N.. LUI

CL)

0

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StabilityPropulsion Reouino ocsit tblt xs AxesForces Reouino ocsit tblt xs Forces __________________

Xp Fxs = Xp cos a + Zp sin a + XA FXS FXE =(Lj cos a + N, sin a)F XS + M, FyS

Yp FyS Y + YAFyS FVE =(L 2cos a + N2 sin a)F XS + 2FY

Z P --l o w F z s = Z p c o s a - X p s in a + Z A F SF E ( 3 c s a + N i ? F S + M y

XA YA ZA a 3tp QBody AxesMoments

a, a ~ -

ASCmuaIono L A L LA cosa -NA sina + L L P= L.C, + N.C2 + (P.-C3

Aerodynamic Forces MA M= A+M . 5 +( )C

ALT and Moments NA M A+PQ=M5+(W-F)C

(Stablity Axes) N NP, Q, R N =LAsina+NA cosa+Np R = N 8 +L + (P.C9

Control Surface LT 8 +6rC

_______________________Propulsion Moments

P U-atdNormalized L, Y (o'

Quatern ions Quaternions Normalize Quaternions Quaternions L2 = 2(7-1 72 +T

2(P. 7 -Q. 7'.73 0 0 N '70 +'71 +'72 3 .7- L3 =2(71 7 3 -

= ~a 0' '1 = 1'N '2 M, = 2(71~ ' 2

1 1!'N M3 2 = ' 7

13 (P - 02 -0., R.-0O) OW3 3 T '"N N 1 =2(7 1 7-3 +r

N2 =2(r 2 -'3 -

N3 = (o 3

FIG. 2: BLOCK DIAGR

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EarthAxes Earth AxesForces _______Velocity Components _________

a)F XS + MFS+ (N cos a L, Lsin a Fzs FXE VNE FEmVE __N2 VE

)FXS + M2FyS + (N2 cosa -L 2 sina) FZS FYE E = FYE /m VEE 2___ = tan' -vC- v

Fxs + M3 Fy5 + (N3 cosU a L3 sin W FZS + W VD E = iZ m VD tan'[E N

Wind VelocityComponents

P 4 Q Rod Axes _ _ _ __EVW

____Angular_____ RatesN

.C, + N.C2 +(P-% + RC 4)Q ap VN VNE -VWN VNE VNE X VNE

X5+ R -P) 6 .PC QVVEE VEE.C+R-) 6RPC E = VEE - W I- - - y VF E

C8+-C PC .3 R -VDE -LVDE

.C+.C+.C-.COVD = VDE -VwD ALT -VDF

VN VE V0

Aircraft VN UB (L IVN + (L2 VE )*(L 3 VD

Directional Velocity Components V

Cosines Relative to Air LVCosine - V (Ml VN )+ (M2VEI (M3 VD

L, = 2 (-,0 + 71' 1 - tan' L/LJV

12 = 2(r 71'2 +70 73) 3W = (Nl1VN I+ (N2 VE +(3V

L3 = 2(7T1 73 -1,0 72 ) 0 tan [L(, + L21, Body Axes B VB~ A 4=, 2(7 17 2 r0' N3 =Velocity ~ *1 3 1

=2( '0'3 -1t a [ M -/ N Components -3t13 N

M3 =2J72 3 +-01 M M' 0 j VTAS (U132 + V8 W8

I1 = 2( 1 3 + 0 2 - - - -P E u ler A ngles a tan 1 [WB3 U B1

N2 = 2(7273- 7071) N,N 2

N3 = 2(701 + 73-P -= tan1 IV8 (UB WB i

OCK DIAGRAM OF COMBINED EARTH AXES/BODY AXES SYSTEM (FLAT EARTH)FOR AIRCRAFT MOTION.

Page 21: OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT ...The various options are discussed by Etkin [2i and other authors, such as Fogarty and Howe [31, and McFarland 15). 3.1 Force Equations In

VG R (VNYE~ + V E E2 VGR IN-GonSpe

r tan' I E VR 0- Flight-Path Angle

tat' [WEE VNE I No Angle of Track

Aircraft'sPositional

_____________ Coordinates

y VFE

ALT -VDE ag

IVE I L3 VID

02VE I ) V

IVE iN3 VD

111111111111 True Airspeed

B 0-- Angle of Attack

L' + WBy 1)" N Angle of Sideslip

Page 22: OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT ...The various options are discussed by Etkin [2i and other authors, such as Fogarty and Howe [31, and McFarland 15). 3.1 Force Equations In

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AUSTRALIA

Department of Defence and Department of Defence Support

Central Office

Chief Defence ScientistDeputy Chief Defence Scientist )Superintendent, Science and Technology Programmes ) (1 copy)Controller, Projects and Analytical StudiesDefence Science Representative (U.K.) (Doc Data sheet only)Counsellor, Defence Science (U.S.A.) (Doc Data sheet only)Defence Central LibraryDocument Exchange Centre, D.I.S.B. (17 copies)Joint Intelligence OrganisationLibrarian H Block, Victoria Barracks, MelbourneDirector General - Army Development (NSO) (4 copies)Defence Industry & Materiel Policy, FAS

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Chief SuperintendentLibrarySuperintendent -AerodynamicsDivisional File - AerodynamicsAuthor: P.H. HallD.A. SecombC.A. MartinR.A. FeikB.F"'. GunnJ.S. DrobikD.A. BirdD.C. Collis

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Defence Research Centre

Library

Central Studies Establishment

Informtation Centre

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Library

../cont.

7

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DISTRIBUTION (CON'T.)

Navy Office

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Army Scientific AdviserEngineering Development Establishment, LibraryRoyal Military College LibraryUS Army Research, Development and Standardisation Group

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Technical Division LibraryDirector General Aircraft Engineering-Air ForceDirector General Operational Requirements-Air ForceHQ Operational ConimandHQ Support Command [SENGSOJRAAF Academy, Point Cook

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Statutory & State Authorities and Industry

Trans-Australia Airlines, LibraryQantas Airways LimitedAnsett Airlines of Australia, LibraryCommonwealth Aircraft Corporation, LibraryHawker de Havilland Aust. Pty. Ltd., Bankstown, Library

.... /cont.

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Page 25: OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT ...The various options are discussed by Etkin [2i and other authors, such as Fogarty and Howe [31, and McFarland 15). 3.1 Force Equations In

C~~ .J I.I P1 ED-j-

SCKAF~_ _ 1.N !."TDoUvnrA Un lw ( w.4WJiiA~~

' e.e e'*'.. t-,ot-s..c ' s al-. &"e .. ~ S',~ e-' ''''n Se'vces Arrinchj.'- t.Cffr-' i-p .ej Pr - .N~ ~b : 2L,01 _______

P-t T'. focu-,nt ma., h' AW46 iONCEIt~ 'ala!, g'ues tj VJfl ~ t'jl.% Znp Ci, ~ ~ b

rfl~~~ C',on ___________ ______________

e.z t nr

The~ ~~~ t~'- i. L, ~ -i.e'a s of aircraft

and bod', u,,- ior tw z~.~ t os, c'i 'i~e trnc'nlrit etqU.1tiqS. The use

So;. r c- tr ts -t.:ito isv ina ss Aatue. irct

PF 65

Page 26: OF FLIGHT DYNAMIC EQUATIONS FOR AIRCRAFT ...The various options are discussed by Etkin [2i and other authors, such as Fogarty and Howe [31, and McFarland 15). 3.1 Force Equations In

Tnis paqe is te be ust, to tecour' erfoiration wtc is requt~u '-y the Establishn',E;i for i-. own k se butwhiO! m~ !'i ot Lip A*ddd to t'~e DISTIS data N-s ucless sec~ficiiy requesteo.

18 0MUMell ReeuE- InMj .~~h9, Ccq '-'ode 2 ~~Ae~~dFro~uo

Mer, r33c) 52 7730

I'M Gcmputer Prag~arns Used -

2. 2teb~s~sentFii* AFlel-

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