2/24/2008
ELF
17
Configuration Drawing Weight / Geometry Flow Path Geometry
Aerodynamics Ramjet Propulsion Rocket Propulsion
Flight Performance House of Quality Paredo Sensitivity for DOE
Inlet
Conical forebody angle, deg 17.7
Ramp wedge angle, deg 8.36
Capture area, ft
2
0.52
Throat area, ft
2
0.29
Body
Length, in 171.0
Diameter, in 20.375
Fineness ratio 8.39
Volume, ft
3
28.33
Wetted area, ft
2
68.81
Base area, ft
2
( cruise ) 0.58
Boattail fineness ratio N/A
Nose half angle, deg 15.0
Tail ( Exposed )
Area ( 2 panels ), ft
2
2.24
Wetted area ( 4 panels ), ft
2
8.96
Aspect ratio ( exposed ) 1.64
Taper ratio 0.70
Root chord, in 16.5
Span, in. ( exposed ) 23.0
L.E. sweep, deg 37.0
M.A.C., in 14.2
Thickness ratio 0.04
X MAC, in 150.5
Y MAC, in ( from root chord ) 5.4
Reference values:
Reference area, ft
2
2.264
Reference length, ft 1.698
•
•
•
•
•
•
•
•
•
•
M, Mach Number
I
sp
, Specific Impulse, sec
1,500
1,000
500
0
0
12 34
Note:
φ = 1
30
20
10
0
01.02.03.04.0
Boost Thrust ~ 1000 lbs
Time ~ sec
5.0 6.0
( I
SP
)
Booster
= 250 sec
3.0
2.5
2.0
Burnout Mach Number
h, Altitude 1,000 ft
2.0
1.0
0
M
L
= 0.80
constant altitude flyout
Boost Range ~ nm
0204060
0204060
80
h, Altitude 1,000 ft
Note: Constant altitude flyout
500
400
300
200
100
0
01 2 3
4
Range ~ nm
M, Mach Number
h = SL
20,000 ft
40,000 ft
60,000 ft
Note:
• M
L
= 0.8, Constant Altitude Flyout
Example:
• Breguet Range for Mach 3 / 60 Kft flyout:
R
max
= V I
SP
( L / D )
Max
ln [ W
BC
/ ( W
BC
- W
f
)]
= 2901 ( 950 ) ( 3.15 ) ln ( 1739 / ( 1739 - 476 )) = 2,777,192 ft or 457 nm
Nose 15.9 15.7
Forebody 42.4 33.5
Guidance 129.0 33.5
Payload Bay 64.5 60.0
Warhead 510.0 60.0
Midbody 95.2 101.2
Inlet 103.0 80.0
Electrical 30.0 112.0
Hydraulic 20.0 121.0
Fuel Distribution 5.0 121.0
Aftbody 44.5 142.5
Engine 33.5 142.5
Tailcone 31.6 165.0
Exit Duct 31.0 165.0
Controls 37.0 164.0
Fins ( 4 ) 70.0 157.2
End of Cruise 1,262.6 81.8
Ramjet Fuel ( 6.9 ft
3
) 476.0 87.0
Start of Cruise 1,738.6 83.2
Boost Nozzle ( Ejected ) 31.0 164.0
Frangible Port 11.5 126.0
End of Boost 1,781.1 84.9
Boost Propellant 449.0 142.5
Booster Ignition 2,230.1 96.5
Component Weight, lb CG Sta, In.
.4
.3
.2
.1
0
C
D
0
M, Mach Number
01234
C
N
δ
~ per deg
01
2
34
C
m
δ
~ per deg
-.4
-.2
0
.10
.05
0
S
Ref
= 2.264 ft
2
L
Ref
= D
Ref
= 1.698 ft
X
cg
@ Sta 82.5 in.
M, Mach Number
+ .4
0
-.4
-.8
-1.2
-1.6
Pitching Moment Coefficient, C
m
α, Angle of Attack ~ deg
04 81216
Mach
4.0
3.0
2.0
1.5
1.2
S
Ref
= 2.264 ft
2
L
Ref
= D
Ref
= 1.698 ft
X
cg
@ Sta 82.5 in.
Normal Force Coefficient, C
N
α, Angle of Attack ~ deg
0481216
Mach
1.2
1.5
2.0
3.0
4.0
.40
.30
.20
.10
0
Axial Force Coefficient, C
A
0481216
Mach
1.2
1.5
2.0
3.0
4.0
S
Ref
= 2.264 ft
2
L
Ref
= D
ref
= 1.698 ft
X
cg
@ Sta 82.5 in.
4.0
3.0
2.0
1.0
0
α, Angle of Attack ~ deg
•
•
•
•
•
•
•
•
•
•
•
•
•
•
20,000
15,000
10,000
5,000
0
01234
M, Mach Number
T, Net Thrust, lb
Note:
φ = 1
h = SL
h = 20K ft
h = 40K ft
h = 60K ft
h = 80K ft
Example of Missile Baseline Data
Example of Missile Baseline Data
A
c
Inlet capture area
A
IT
Inlet throat area
S
Ref
Reference area
A
5
Nozzle throat area
I
sp
Specific impulse
φ Equivalence ratio – operating fuel / air ratio divided by fuel / air ratio for stochiometric combustion
Ramjet Engine Station Identification
0
Free Stream
23
4
5
6
Subscripts
0 Free stream conditions ( Ramjet Baseline A
0
= 75.4 in
2
at Mach 4, α = 0 deg, Note: A
C
= 114 in
2
)
1 Inlet throat ( Ramjet Baseline A
1
= A
IT
= 41.9 in
2
)
2 Diffuser exit ( Ramjet Baseline A
2
= 77.3 in
2
)
3 Flame holder plane ( Ramjet Baseline A
3
= 287.1 in
2
)
4 Combustor exit ( Ramjet Baseline A
4
= 287.1 in
2
)
5 Nozzle throat ( Ramjet Baseline A
5
= 103.1 in
2
)
6 Nozzle exit ( A
6
= 233.6 in
2
)
Ref Reference Area ( Ramjet Baseline Body Cross-sectional Area, S
Ref
= 326 in
2
)
1
Inlet Throat
( C
D
0
)
Nose Corrected
= ( C
D
0
)
Nose Uncorrected
x ( 1 -
c
S
REF
)
120°
A
c
= 114 in
2
20.375 in diameter
Source: Bithell, R.A. and Stoner, R.C. “Rapid Approach for Missile Synthesis”, Vol. II, Air-breathing
Synthesis Handbook, AFWAL TR 81-3022, Vol. II, March 1982.
Sta 0.
Guidance
Warhead
Ramjet Fuel
Boost Propellant
Booster, and
Ramjet Engine
Boost Nozzle
Tail Cone
Aft-bodyMid-bodyPayload Bay
Fore-body
Nose
23.5 43.5 76.5
126.0
159.0
171.0
Sta 150.3
11.6
11.5
16.5
37°
Note: Dimensions are in inches
Chin
Inlet
Transport Air Duct
20.375 dia
-1
-0.5
0
0.5
1
1.5
ISP Fuel
Weight
Thrust CD0, Zero-
Lift Drag
Coefficient
CLA, Lift-
Curve-
Slope
Coefficient
Inert
Weight
Parameter
Nondimensional Range Sensitivity
to Parameter
Sea Level Flyout at Mach 2.3 20 Kft Flyout at Mach 2.5
40 Kft Flyout at Mach 2.8 60 Kft Flyout at Mach 3.0