12 performance of an aircraft with parabolic polar
TRANSCRIPT
08/12/15 1
Performance of an Aircraft with Parabolic Polar
SOLO HERMELIN
Updated: 14.03.2004
08/12/15 2
Performance of an Aircraft with Parabolic PolarSOLO
Table of Content
Flat Earth Three Degrees of Freedom Aircraft Equations
Performance of an Aircraft with Parabolic Polar
Aircraft Drag
Energy per unit mass E
Load Factor n
Aircraft Trajectories
Summary
Constraints
Horizontal Plan Trajectory ( )0,0 == γγ
Horizontal Turn Rate as Function of ps, n
Horizontal Turn Rate as Function of nV ,
References
08/12/15 3
SOLO
Assumptions:
•Point mass model.•Flat earth with g = constant.•Three-dimensional aircraft trajectory.•Air density that varies with altitude ρ=ρ(h)•Drag that varies with altitude, Mach number and control effort D = D(h,M,n)•Thrust magnitude is controllable by the throttle. •No sideslip angle.•No wind.
α
T
V
L
D
Bx
Wx
Bz
Wz
Wy
By
Aircraft Coordinate System
Flat Earth Three Degrees of Freedom Aircraft Equations
4
SOLO
• Rotation Matrix from Earth to Wind Coordinates
[ ] [ ] [ ]321 χγσ=WEC
whereσ – Roll Angleγ – Elevation Angle of the Trajectoryχ – Azimuth Angle of the Trajectory
Force Equation:
amgmTFA
=++
where:
• Aerodynamic Forces (Lift L and Drag D)( )
−
−=
L
D
F WA 0
• Thrust T ( )
=
α
α
sin
0
cos
T
T
T W
• Gravitation acceleration
( ) ( )
−
−
−==
g
cs
sc
cs
sc
cs
scgCg EWE
W 0
0
100
0
0
0
010
0
0
0
001
χχχχ
γγ
γγ
σσσσ
( ) g
cc
cs
s
g W
−=
γσγσ
γ
α
T
V
L
D
Bx
Wx
Bz
Wz
Wy
By
Flat Earth Three Degrees of Freedom Aircraft Equations
5
SOLO
α
T
V
L
D
Bx
Wx
Bz
Wz
Wy
By
• Aircraft Acceleration
( )( )
( ) ( )WWW
W VVa ×+=
→
ω
where:
( )
=
0
0
V
V W
and( )
=
→
0
0
V
VW
( )
−+
−+
−=
=
χχχχχ
γγγ
γγσ
σσσσω
0
0
100
0
0
0
0
0
010
0
0
0
0
0
001
cs
sc
cs
sc
cs
sc
r
q
p
W
W
W
W
or ( )
+−+
−=
=
γσχσγγσχσγγχσ
ωccs
csc
s
r
q
p
W
W
W
W
therefore( )
( )( ) ( ) ( )
( )
+−+−=
−=×+=
→
γσχσγγσχσγω
cscV
ccsV
V
qV
rV
V
VVa
W
WWW
WW
Flat Earth Three Degrees of Freedom Aircraft Equations
6
SOLO
α
T
V
L
D
Bx
Wx
Bz
Wz
Wy
By
• Aircraft Acceleration
Flat Earth Three Degrees of Freedom Aircraft Equations
From the Force equation we obtain:
( )( )
( ) ( ) ( ) ( )( ) ( )WWWA
WWW
W gTFm
VVa ++=×+=
→ 1ω
or
( )( ) ( ) σ
σσσ
γσαγσχσγγσγσχσγ
γα
s
c
c
s
ccgmLTcscVqV
csgccsVrV
sgmDTV
W
W
−−−
++−=+−=−=+−=
−−=
/sin
/)cos(
from which we obtain:
( )( )
+=−+=
−−=
msLTcV
cgmcLTV
sgmDTV
/sin
/sin
/)cos(
σαγχγσαγ
γα
Define the Load Factor
gm
LTn
+= αsin:
7
SOLO
α
T
V
L
D
Bx
Wx
Bz
Wz
Wy
By
• Velocity Equation
Flat Earth Three Degrees of Freedom Aircraft Equations
( ) ( )
==
=
0
0
V
CVC
h
y
x
V EW
WEW
E
−
−
−=
0
0
0
0
001
0
010
0
100
0
0 V
cs
sc
cs
sc
cs
sc
h
y
x
σσσσ
γγ
γγχχχχ
=
==
γχγχγ
sVh
scVy
ccVx
or
• Energy per unit mass E
g
VhE
2:
2
+=
Let differentiate this equation:( )
W
VDT
W
DTg
g
VV
g
VVhEps
−=
−−+=+== αγαγ cos
sincos
sin:
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8
SOLO Flat Earth Three Degrees of Freedom Aircraft Equations
Summary
γχγχγ
sin
sincos
coscos
Vh
Vy
Vx
=
==
( )
( )
σγ
σγ
αχ
γσγσαγ
αγα
sincos
sincos
sin
coscoscoscossin
cossin
cos
n
V
g
W
LT
V
g
nV
g
W
LT
V
g
W
VDTEor
W
DTgV
=+=
−=
−+=
−=−
−=
wheremgW =
Aircraft Thrust( ) 10, ≤≤= ηη VhTT MAX
( ) ( )MSCVhL L ,2
1 2 αρ=
( ) ( )LD CMSCVhD ,2
1 2ρ=
( ) ( ) ( ) 20, LDLD CMKMCCMC +=
( ) 0/0
hheh −= ρρ
( ) ( ) soundofspeedhaNumberMachMhaVM === &/
Aircraft Weight
Aircraft Lift
Aircraft Drag
Parabolic Drag Polar
Return to Table of Content
9
SOLO Flat Earth Three Degrees of Freedom Aircraft Equations
Constraints:
State Constraints
• Minimum Altitude Limit minhh ≥
• Maximum dynamic pressure limit ( ) ( )hVVorqVhq MAXMAX ≤≤= 2
2
1 ρ
• Maximum Mach Number limit ( ) MAXMha
V ≤
Aerodynamic or heat limitation
Control Constraints
• Maximum Lift Coefficient or Maximum Angle of Attack
( ) ( ) ( )VhorMCMC STALLMAXLL ,, _ ααα ≤≤
• Minimum Load Factor ( )MAXn
W
VhLn ≤= ,
• Maximum Thrust ( )VhTT MAX ,≤
10
SOLO Flat Earth Three Degrees of Freedom Aircraft Equations
MAXα MAXα
αα
LCDC
MAXLC
0DC
( ) ( )αα 20 LDD kCCC +=
Drag and Lift Coefficients as functions of Angle of Attack
11
SOLO Flat Earth Three Degrees of Freedom Aircraft Equations
( ) ( )( )
Limit
Vhor
MCMC
STALL
MAXLL
,
, _
ααα
=
=
( )( )
Limit
hVVor
qVhq
MAX
MAX
=
== 2
2
1 ρ
minhh =
MAXMM =
Mach
Altitude
Flight Envelope of the Aircraft
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12
Performance of an Aircraft with Parabolic PolarSOLO
W
LTn
+= αsin:'
W
Ln =:
20
:LD
L
D
L
CkC
C
CSq
CSq
D
Le
+===
We assumed a Parabolic Drag Polar:2
0 LDD CkCC +=
Let find the maximum of e as a function of CL
( ) ( ) 02
220
20
220
220 =
+
−=+
−+=∂∂
LD
LD
LD
LLD
L CkC
CkC
CkC
CkCkC
C
ee
LC*LC
*2
1
LCk
CL/CD as a function of CL
The maximum of e is obtained for
k
CC DL
0* =
( ) 00
02
0 2** DD
DLDD Ck
CkCCkCC =+=+=
Start with
Load Factor
Total Load Number
Lift to Drag Ratio
Climbing Aircraft Performance
13
Performance of an Aircraft with Parabolic PolarSOLO
e
LC*LC
*2
1
LCk
CL/CD as a function of CL
The maximum of e is obtained for
k
CC DL
0* =
( ) 00
02
0 2** DD
DLDD Ck
CkCCkCC =+=+=
*2
1
*2
1
2
1
2*
**
2200
0
LLDD
D
D
L
CkCkCkCkC
C
Ce =====
We have WnCSVCSqL LL === 2
2
1 ρ
Let define for n = 1
=
=
==
2
0
*2
1:*
*:
2
*21
:*
Vq
V
Vu
CS
kW
CS
WV
DL
ρ
ρρ
20
:LD
L
D
L
CkC
C
CSq
CSq
D
Le
+===
Climbing Aircraft Performance
14
Performance of an Aircraft with Parabolic PolarSOLO
Using those definitions we obtain
L
L
L
L
C
Cnqq
WCSq
WnCSqL **
**=→
===
22
2
1
21
*21
*
uV
Vn
q
q ==ρ
ρ
2
**
*
u
CnC
q
qnC L
LL ==
( )
+=
+=
+=+=
=
2
22
0402
02
*
4
22
022
0
**
**
02
u
nuCSq
u
CnCuSq
u
CnkCuSqCkCSqD
DD
D
CCk
LDLD
DL
*2
1
**** 0
0 eW
C
CCSqCSq
L
DLD ==
+=
2
22
*2 u
nu
e
WD
Therefore
Return to Table of Content
Climbing Aircraft Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
15
Performance of an Aircraft with Parabolic PolarSOLO
We obtained
Let find the minimum of D as function of u.
nu
u
nu
e
W
u
nu
e
W
u
D
=→
=−=
−=
∂∂
2
3
24
3
2
0*
22*2
*2min e
WnDD
nu==
=
Aircraft Drag
Climbing Aircraft Performance
u 0
- - - - 0 + + + + +
D ↓ min ↑
n
u
D
∂∂
+=
2
22
*2 u
nu
e
WD
16
Performance of an Aircraft with Parabolic PolarSOLO
Aircraft Drag
( )MAXn
W
VhLn ≤= ,
+=
= 2
22
*2 u
nu
e
WD MAX
nn MAX
Maximum Lift Coefficient or Maximum Angle of Attack( ) ( ) ( )VhorMCMC STALLMAXLL ,, _ ααα ≤≤
We have
uC
C
u
n
u
CnC
q
qnC
L
MAXL
CC
LLL
MAXLL*
**
* _
2
_
=→===
2
2
_
2
2
_2
*1
*2
**2_
uC
C
e
W
uC
Cu
e
WD
L
MAXL
L
MAXL
CC MAXLL
+=
+=
=
Maximum dynamic pressure limit
( ) ( ) MAXMAX
MAXMAX uV
VuhVVorqVhq =<→≤≤= :
*2
1 2ρ
*eW
D
MAXLC _
2
2
_12
1u
C
C
L
MAXL
+
+=
2
22
2
1*
u
nue
W
D MAX
LIMIT
nn MAX=
2min * ueW
D =
+=
2
22
2
1*
u
nue
W
D
MAXuu =MAX
MAXL
LCORNER n
C
Cu
_
*=
n
LIMIT
uMAXnu =
as a function of u*eW
D
Return to Table of Content
Climbing Aircraft Performance
Maximum Load Factor
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
17
Performance of an Aircraft with Parabolic PolarSOLO
Energy per unit mass ELet define Energy per unit mass E: g
VhE
2:
2
+=Let differentiate this equation:
( ) ( )W
VDT
W
VDT
W
DTg
g
VV
g
VVhEps
−≈−=
−−+=+== αγαγ cos
sincos
sin:
*&*2 2
22 VuVu
nu
e
WD =
+=
Define *: eW
Tz
=
We obtain( )
+−=
+−
=−=2
22
2
22
2
1
*
**
2
1*
*
u
nuzu
e
V
W
Vuu
nue
W
T
e
W
W
VDTps
or ( )u
nuzu
e
Vps
224 2
*2
* −+−=
nznzzu
nzzunuzup
constns>
−+=
−−=→=+−→=
=22
2
221224 020
( ) ( )2
224
2
2243 23
*
*244
*
*
u
nuzu
e
V
u
nuzuuuzu
e
V
u
p
constn
s ++−=−+−−+−=∂
∂
=
3
30
22 nzzu
u
pMAX
constn
s ++=→=
∂∂
=
221
2uu
uuMAX <<+
nz >
Climbing Aircraft Performance
Performance of an Aircraft with Parabolic PolarSOLO
Energy per unit mass E
g
VhE
2:
2
+=
Climbing Aircraft Performance
Energy Height versus Mach NumberEnergy Height versus True Airspeed
( )hV
VM
sound
=:( )00
:T
TV
T
TMhVTAS sound ==
19
Performance of an Aircraft with Parabolic PolarSOLO
Energy per unit mass Esp
2u1u MAXu2
21 uu + u
MAXn
n
1=n
( )u
nuzu
e
Vps
224 2
*
* −+−=
ps as a function of u
( )u
nuzu
e
Vps
224 2
*
* −+−=
uV
peuzunnuzuu
V
pe ss
*
*222
*
*2 242224 −+−=→−+−=
From which uV
peuzun s
*
*22 24 −+−=
( )*
*244 3
2
V
peuzu
u
n s
constps
−+−=∂
∂
=
( )3
0412 22
22 zuzu
u
n
constps
=→=+−=∂
∂
=
Return to Table of Content
Climbing Aircraft Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
20
Performance of an Aircraft with Parabolic PolarSOLO
Load Factor n
u
3
z z
z2z3
z
u
2n
0=sp
0>sp
0<sp
0<sp
0=sp
0>sp
( )u
n
∂∂ 2
( )2
22
u
n
∂∂
3
zu
( ) ( ) 22
2
22
,, nu
n
u
n
∂∂
∂∂ as a function of u
uV
peuzun s
*
*22 24 −+−=
( )3
0412 22
22 zuzu
u
n
constps
=→=+−=∂
∂
=
( )*
*244 3
2
V
peuzu
u
n s
constps
−+−=∂
∂
=
Climbing Aircraft Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
21
Performance of an Aircraft with Parabolic PolarSOLO
Load Factor nFor ps = 0 we have
zuuzun 202 24 ≤≤+−=
Let find the maximum of n as function of u.
022
4424
3
=+−+−=
∂∂
uzu
uzu
u
n
Therefore the maximum value for n is achieved for zu =
( ) znMAXps
==0
u 0 √z √2z
∂ n/∂u | + + + 0 - - - - | - -
n ↑ Max ↓
z2z
u
n
0=sp
0>sp
0<sp
MAXn
z
MAXMAXL
L nC
C
_
*
n as a function of u
Return to Table of Content
Climbing Aircraft Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
22
Performance of an Aircraft with Parabolic PolarSOLO
−+=
=
γσα
γσ
coscossin
cossin
V
g
Vm
LTq
V
gr
W
W
nW
L
W
LTn =≈+= αsin
:'
Therefore
( )
−=
=
γσ
γσ
coscos'
cossin
nV
gq
V
gr
W
W
γσγσγσω 2222222 coscoscoscos'2'cossin +−+=+= nnV
gqr WW
or
γγσω 22 coscoscos'2' +−= nnV
g
γγσω 22
2
coscoscos'2'
1
+−==
nng
VVR
Aircraft Trajectories
We found
Aircraft Turn Performance
23
Performance of an Aircraft with Parabolic PolarSOLO
( ) ( )
( )γσφ
γαχ
γσγσαγ
cos
sinsin
cos
sin
coscos'coscossin
V
gLT
nV
g
V
g
Vm
LT
=+=
−=−+=
2. Horizontal Plan Trajectory ( )0,0 == γγ
( )
1'
1
1''
11'sin'
cos
1'01cos'
2
2
22
−=
−=
−==
=→=−=
ng
VR
nV
g
nn
V
gn
V
g
nnV
g
σχ
σσγ
Aircraft Turn Performance
1. Vertical Plan Trajectory (σ = 0)
( )
γ
γγ
χ
cos'
1
cos'
0
2
−=
−=
=
ng
VR
nV
g
24
Vertical Plan Trajectory (σ = 0) SOLO
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25
Performance of an Aircraft with Parabolic PolarSOLO
2. Horizontal Plan Trajectory ( )0,0 == γγ
We can see that for n > 1
1
1
1'
1
11'
2
2
2
2
22
−≈
−=
−≈−=
ng
V
ng
VR
nV
gn
V
gχ
We found that2
2 *
*u
C
Cn
u
CnC
L
LLL =→=
n
1n
2n
MAXn
u u
LC
MAXLC _
1_
nC
C
MAXL
LMAX
MAXL
Lcorner n
C
Cu
_
*=
*2 L
MAXL C
u
nC =
MAXMAXL
Lcorner n
C
Cu
_
*= MAXL
L nC
C
1
*
MAXLC _
2LC
1LC
2
*1 u
C
Cn
L
L=
MAXn
n, CL as a function of u
Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
26
R
V=:χ1'2 −= nV
gχ
Contours of Constant n and Contours of Constant Turn Radiusin Turn-Rate in Horizontal Plan versus Mach coordinates
Horizontal Plan Trajectory SOLO
27
Performance of an Aircraft with Parabolic PolarSOLO
MAX
MAX
L
MAXL
n
n
C
C
V
g 1
**
2_ −
MAXMAXL
Lcorner n
C
C
V
gu
_
*
*=
MAXL
L
C
C
V
gu
_1
*
*=
MAXn
2n1n
MAXLC _
2LC
1LC
u
χ
MAXu
a function of u, with n and CL as parameters χ
We defined 2
*&
*: u
C
Cn
V
Vu
L
L==
We found 22
2
22 1
**1
*1
uu
C
C
V
gn
Vu
gn
V
g
L
L −
=−=−=χ
This is defined for 1:**
1__
<=≥≥= uC
Cun
C
Cu
MAXL
LMAX
MAXL
Lcorner
2. Horizontal Plan Trajectory ( )0,0 == γγ
Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
28
Performance of an Aircraft with Parabolic PolarSOLO
From2
2
2
22 1
**1
*1
uu
C
C
V
gn
Vu
gn
V
g
L
L −
=−=−=χ
4
2
2
2
22
1
*
1*
1
*:
uC
Cg
V
n
u
g
VVR
L
L −
=
−==
χ
Therefore
cornerMAXMAXL
L
MAXL
L
L
MAXL
Cun
C
Cu
C
Cu
uC
Cg
VR
MAXL=≤≤=
−
=
__1
4
2
_
2 **
1
*
1*_
cornerMAXMAXL
L
MAX
nun
C
Cu
n
u
g
VR
MAX=≥
−=
_2
22 *
1
*
MAXL
L
L
L
L
L
Cn
C
Cu
C
Cu
uC
Cg
VR
L
**
1
*
1*1
4
2
2
≤≤=
−
=
nC
Cu
n
u
g
VR
MAXL
Ln
_2
22 *
1
* ≥−
=
2. Horizontal Plan Trajectory ( )0,0 == γγ
Aircraft Turn Performance
29
Performance of an Aircraft with Parabolic PolarSOLO
R (Radius of Turn) a function of u, with n and CL as parameters
1
**2
_
2
−MAX
MAX
MAXL
L
n
n
C
C
g
V
MAXMAXL
Lcorner n
C
C
V
gu
_
*
*=
MAXL
L
C
C
V
gu
_1
*
*=
MAXn
2n
1nMAXLC _
2LC 1L
C
u
R
4
2
2
2
22
1
*
1*
1
*:
uC
Cg
V
n
u
g
VVR
L
L −
=
−==
χ
2. Horizontal Plan Trajectory ( )0,0 == γγ
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Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
30
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n ( )
u
nuzu
e
Vps
224 2
*2
* −+−=
upV
euzun s*
*22 242 −+−=
2
24
2
2 1*
*22
*
1
* u
upV
euzu
V
g
u
n
V
g s −−+−=−=χ
2
24
4
2423
1*
*22
2
1*
*222
*
*244
*
u
upV
euzu
u
upV
euzuuup
V
euzu
V
g
us
ss
−−+−
−−+−−
−+−
=∂∂ χ
Therefore
−−+−
++−=
∂∂
1*
*22
1*
*
*244
4
upV
euzuu
upV
eu
V
g
us
sχ
For ps = 0
222
12
24
011
12
*uzzuzzu
u
uzu
V
gsp
=−+<<−−=−+−==
χ
( ) 222
1244
4
0
1112
1
*uzzuzzu
uzuu
u
V
g
usp
=−+<<−−=−+−
+−=∂∂
=
χ
Aircraft Turn Performance
31
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
For ps = 0
222
12
24
011
12
*uzzuzzu
u
uzu
V
gsp
=−+<<−−=−+−==
χ
( ) 222
1244
4
0
1112
1
*uzzuzzu
uzuu
u
V
g
usp
=−+<<−−=−+−
+−=∂∂
=
χ
Let find the maximum of as a function of u χ
( )12
1
* 244
4
0 −+−
+−=∂∂
= uzuu
u
V
g
usp
χ
( ) ( )12*
100
−=====
zV
gu
ss ppMAX χχ
u 0 u1 1 (u1+u2)/2 u2
∞ + + 0 - - - - - - -∞
↑ Max ↓
u∂∂ χ
χ
From
2
24 1*
*22
* u
upV
euzu
V
g s −−+−=χ
−−+−
++−=
∂∂
1*
*22
1*
*
*244
4
upV
euzuu
upV
eu
V
g
us
sχ
Aircraft Turn Performance
32
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
u
u
0<sp
0<sp
0=sp
0=sp 0>sp
0>sp
χ
u∂∂ χ
( )12*
−zV
g
1=u1u2u
as a function of u with ps asparameter
u∂∂ χχ
,
−−+−
++−=
∂∂
1**2
2
1**
* 244
4
upVe
uzuu
upVe
u
V
g
us
sχ
2
24 1**2
2
* u
upVe
uzu
V
g s −−+−=χ
Because ,we have0*
* >uV
e
000 >=<>>
sss pppχχχ
01
01
01
0>
==
=<
= ∂∂<=
∂∂<
∂∂
sss pu
pu
pu uuu
χχχ
Aircraft Turn Performance
33
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
u
0<sp
0=sp
0>sp
χ
( )12*
−zV
g
1=u1u2u
2
24 1**2
2
* u
upVe
uzu
V
g s −−+−=χ
1*
2 −MAXnuV
g
22
2
_ 1
** uu
C
C
V
g
L
MAXL −
MAXL
L
C
C
_
*
MAXMAXL
L nC
C
_
*
LIMIT
nMAXLIMIT
C MAXL_
MAX
MAX
L
MAXL
n
n
C
C
V
g 1
**
2_ −
a function of u, with ps as parameter
χ
2
24 1**2
2
* u
upVe
uzu
V
g s −−+−=χ
Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
34
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
2
24 1*
*22
* u
upV
euzu
V
g s −−+−=χ
( ) ( )ss
s
puupuup
V
euzu
u
g
VVR 21
24
42
1*
*22
* <<−−+−
==χ
3242
232
24
4
224
34243
2
1*
*222
2*
*322
*
1*
*22
2
1*
*22
*
*2441
*
*224
*
−−+−
−−
=
−−+−
−−+−
−+−−
−−+−
=∂∂
upV
euzuu
upV
euzu
g
V
upV
euzu
u
upV
euzu
pV
euzuuup
V
euzuu
g
V
u
R
s
s
s
s
ss
Aircraft Turn Performance
35
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
324
22
1*
*22
2*
*32
*
−−+−
−−
=∂∂
upV
euzu
upV
euzu
g
V
u
R
s
s
or
We have
>+
+
=
<+
−
=→=
∂∂
04
16*
*9
*
*3
04
16*
*9
*
*3
02
2
2
1
z
zpV
eup
V
e
u
z
zpV
eup
V
e
u
u
R
ss
R
ss
R
u 0 u1 uR2 u2
∞ - - - 0 + + ∞
↓ min ↑
u
R
∂∂
R
222
124
42
011
12
*uzzuzzu
uzu
u
g
VR
sp=−+<<−−=
−+−=
=
( )( ) 2
221324
22
0
1112
1*2uzzuzzu
uzu
uzu
g
V
u
R
sp
=−+<<−−=−+−
−=∂∂
=
Aircraft Turn Performance
36
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of ps, n
u
R
0>sp0=sp
0<sp
MAXL
L
C
C
_
*
1
**2
_ −MAX
MAX
MAXL
L
n
n
C
C
g
V
1
1*2 −zg
V
4
2
_
1*
1*
uC
Cg
V
MAXL
L −
1
*2
22
−MAXn
u
g
V
MAXMAXL
L nC
C
_
*
LIMIT
C MAXL_
LIMIT
nMAX
z
1
12 −− zz 12 −+ zz
1**2
2
*
24
42
−−+−=
upVe
uzu
u
g
VR
s
The minimum of R is obtained for zu /1=
1
1*2
2
0 −=
=zg
VR
sp
R (Radius of Turn) a function of u, with ps as parameter
( ) ( )ss
s
puupu
upVe
uzu
u
g
VVR
21
24
42
1**2
2
*
<<
−−+−==
χ
Return to Table of Content
Because ,we have0*
* >uV
e000 >=<
<<sss ppp
RRR000 minminmin >=<
<<sss pRpRpR uuu
Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
37
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of nV ,
( )W
VDT
g
VVhEps
−≈+==
:
For an horizontal turn 0=h
Vg
Vu
g
VVps
*==
We found2
24 1*
*22
* u
upV
euzu
V
g s −−+−=χ
from which2
24 1*2
* u
uegV
zu
V
g−
−+−
=
χ
defined for
2
22
1 :1**1**: ueg
Vze
g
Vzue
g
Vze
g
Vzu =−
−+
−≤≤−
−−
−=
Aircraft Turn Performance
38
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of nV ,
Let compute
2
24
4
2423
1*2
2
1*22*44
*
u
ueg
Vzu
u
ueg
Vzuuuue
g
Vzu
V
g
u−
−+−
−
−+−−
−+−
=∂∂
χ
−
−+−
+−=∂∂
1*2
1
*244
4
ueg
Vzuu
u
V
g
u
χ
or u 0 u1 1 (u1+u2)/2 u2
∞ + + 0 - - - - - - -∞
↑ Max ↓
u∂∂ χ
χ
−−= 1*2
*e
g
Vz
V
gMAX
χ
Aircraft Turn Performance
39
Performance of an Aircraft with Parabolic PolarSOLO
Horizontal Turn Rate as Function of nV ,
u
0<V
0=V
0>V
χ
( )12*
−zV
g
1=u1u2u
2
24 1*2
* u
uegV
zu
V
g−
−+−
=
χ
1*
2 −MAXnuV
g
22
2
_ 1
** uu
C
C
V
g
L
MAXL −
MAXL
L
C
C
_
*
MAXMAXL
L nC
C
_
*
LIMIT
nMAXLIMIT
C MAXL _
MAX
MAX
L
MAXL
n
n
C
C
V
g 1
**
2_ −
as function of uand as parameterχ
V
Return to Table of Content
Aircraft Turn Performance
=
=
=
2
0
*2
1:*
*:
2:*
Vq
V
Vu
CS
kWV
D
ρ
ρ
08/12/15 40
Performance of an Aircraft with Parabolic PolarSOLO
References
Angelo Miele, “Flight Mechanics, Volume I, Theory of Flight Paths”, Addison-Wesley, 1962
Return to Table of Content
S. Hermelin, “3 DOF Model of Aircraft in Earth Atmosphere”
41
SOLO
TechnionIsraeli Institute of Technology
1964 – 1968 BSc EE1968 – 1971 MSc EE
Israeli Air Force1970 – 1974
RAFAELIsraeli Armament Development Authority
1974 – 2013
Stanford University1983 – 1986 PhD AA