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Michael Ferguson
Matt Magnuson
Christopher Fridley
Haithem Taha
Subsonic Unmanned Combat Aerial Vehicle (UCAV)
Launched from Aircraft Carrier/ Airfield
Used as Advanced Recon / Bomber in the field
X-47A was a proof of concept Vehicle
http://en.wikipedia.org/wiki/Northrop_Grumman_X-47A_Pegasus
www.popsci.com
Scaled Composites X-47A Three View with Facts and Figures http://air-attack.com/page/28/X-47-Pegasus-UCAV-N.html.
Northrop Grumman X-47 UCAV Three View. http://www.as.northropgrumman.com/products/nucasx47b/assets/X-
47B-UCAS-Fact-Sheet.pdf. 4/19/2011.
Length: 27.9 ft
Height: 6.1ft
Wingspan: 27.8ft
Empty Weight: 3,835 lbs
TOGW: 5500 lbs
Payload: 500 lbs
Powerplant: P&W JT15D-5C Turbofan Engine
Length: 38.2 ft
Height: 10.4 ft
Wingspan: 62.1 ft
Empty Weight: 14,000 lbs
TOGW: 44,567 lbs
Payload: 4500 lbs
Powerplant: P&W F100-220U Turbofan Engine
X-47 A X-47B
X47A Value Units
C_root 27.9 ft
C_tip 0 ft
Sref 387.81 ft2
Control Surface
Area 26.93 ft2
Moment Arm 10.28 ft
Aspect Ratio 1.99
Leading Edge Sweep 55.00 degrees
Trailing Edge Sweep 30.00 degrees
MAC 18.60 ft
yMAC 4.63 ft
t/c max 0.12
Tailscrape: 20 degrees
L/Dcruise = 5.58
Cruise Speed: Mach 0.45
Range: 953 Miles
Max Endurance: 6.0 hours
W/S = 14.52
T/W = 0.58
Service Ceiling: 54 kft
Airfoil: NACA 641-212
Elevator Required to Trim: (-6.8o)
L/Dcruise = 12.62
Cruise Speed: Mach 0.45
Range: 2461 Miles
Max Endurance: 6.6 hours
W/S = 46.2
T/W = 0.38
T/Waugmented = 0.56
Service Ceiling: 40 kft
Airfoil: NACA 641-212
Elevator Required to Trim: (-23.4o)
X-47 A X-47B
X47B Value Units
Sref1 335.08 ft2
Sref2 91.49 ft2
Sref3 18.26 ft2
Sref4 9.73 ft2
Total: Sref 909.11 ft2
Control Surface Area 98.70 ft2
Inner moment arm 14.51 ft
Outer moment arm 23.556 ft
Tailscrape: 41 degrees
-0.5
0
0.5
0 0.2 0.4 0.6 0.8 1 1.2
Y/C
X/C
NACA 641212
Attributes: • maintain a lower radar cross section • uniform pressure distribution • NACA 641212, low drag at low angles of attack
Aerodynamic Specifications
Y/C
Flying wing
Carrier Launched
Corrosive Salt-Water Environment
Unmanned
Stealth
Multi-role
Reconnaissance
Combat
X-47 Final Concept Art
www.unmannedwarfare.webs.com
• Spoilers
Rapid deceleration
Rapid descent
Generate roll
Spoiler Spoiler
X-47B in Landing Configuration www.technewsdaily.com
AVL Modeling & Drag Buildup
12.9
12.91
12.92
12.93
12.94
12.95
12.96
12.97
12.98
-100 400 900 1400 1900 2400
21.47
21.48
21.49
21.5
21.51
21.52
21.53
21.54
-100 400 900 1400 1900 2400
Number of Panels Number of Panels
Neutral Point Location
X-47 A X-47B
Modeled via AVL
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
-20 -10 0 10 20 30 40 50
Static Margin -%c
X-47A
X-47B
CD
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
CD
CL
Drag Polars At the Cruise Mach Number
X47 AX47 B
Cruise Points
X-47A
W/S = 14.52
T/W = 0.58
X-47B
W/S = 46.2
T/W = 0.38
CL
Modeled via AVL
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 112
12.5
13
13.5
14
14.5
15
15.5
16
16.5
Mach Number, M
Lift
to D
rag
Ratio L
/DL/D as a function of Mach Number
X47 A
X47 B
Note the maximum attainable atthe cruise Mach. But this requiresflying at high CL. So the cruisevalues are 5.58 for A, 12.62 for B
Type equation here. Lift/Drag
0 10 20 30 40 50 600
2000
4000
6000
8000
10000
12000
14000
Altitude (kft), M
Ma
xim
um
Ra
te o
f C
limb (
ft/m
in)
Max Rate Of Climb
X47 A
X47 B
MROC (ft/min)
Max Rate of Climb “MROC” vs. Altitude
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10
200
400
600
800
1000
1200
1400
1600
1800
Mach Number, M
Ra
ng
e (
Mile
s)
Range as a Function of Mach Number
X47 A
X47 B
Very big range extension for the X47 BAlso note that the Mach for best rangeis exactly the cruise one (0.45).It seems that X47 A is redesigned for greaterrange
Range (mi)
0 200 400 600 800 1000 12000
10
20
30
40
50
60
V (ft/sec)
Altitd
e (
kft)
The Flight Envelope
X47 A
X47 B
Alt. (kft)
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 10
0.01
0.02
0.03
0.04
0.05
0.06
Load Distributions
X47 B
X47 A
CL = 0.154Cruise CL for X47 B
These are determined using 0.05 taper ratio to avoid infinite sectional lift coefficient at tips.
γ
Modeled via VLM
-1 -0.5 0 0.5 10
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Cl/C
LSection Lift Coefficient Ratio
X47 B
X47 A
Cl/CL
Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-2
-1.8
-1.6
-1.4
-1.2
-1
-0.8
-0.6
-0.4
-0.2
0
Cp Distribution for X47 A at the cruise C
L
-0.15
-0.1
-0.05
0
0.05
0.1
CP
η
CL
Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-2
-1.8
-1.6
-1.4
-1.2
-1
-0.8
-0.6
-0.4
-0.2
0
Cp Contours for X47 A at the cruise C
L
-0.15
-0.1
-0.05
0
0.05
0.1
CP CL
η Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-1.4
-1.2
-1
-0.8
-0.6
-0.4
-0.2
0
Cp Distribution for the X47 B at the cruise C
L
-2
-1
0
1
2
3
4
x 10-3
CP CL
η Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-1.4
-1.2
-1
-0.8
-0.6
-0.4
-0.2
0
Cp Contours for the X47 B at the cruise CL
-2
-1
0
1
2
3
4x 10
-3CP
η Modeled via VLM
CG: 𝑋𝑐𝑔
𝐶 =0.46 MAC
Static Margin: -8%
Neutral Point: 𝑋𝑛𝑝
𝐶 =0.54 MAC
CG: 𝑋𝑐𝑔
𝐶 =0.23 MAC
Static Margin: -.65%
Neutral Point: 𝑋𝑛𝑝
𝐶 = 0.24 MAC
X-47 A X-47B
𝑐 is the mean aerodynamic chord.
-0.5 0 0.5 1 1.5-0.1
-0.08
-0.06
-0.04
-0.02
0
0.02
0.04
0.06
0.08
CL
CM
cg
Cm Vs CL
Zero control surfaces deflection with 2% cambered 6-series, no twist
X47 A
X47 B
CMcg
Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 10.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Tw
ist
(deg
)
Twist Distibution for Minimum Induced Drag with Trim for X47 B
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 10
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Tw
ist
(deg
)
Twist Distibution for Minimum Induced Drag with Trim for X47 A
X-47A: Camber and Twist distribution led to a reduction in induced drag from 43 counts to 1.1 counts.
X-47B: Reduction from 87 counts to 5.6 counts.
Modeled via VLM
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10
1
2
3
4
5
6x 10
-3
X
Zcam
be
r
Camber Distibution for Minimum Induced Drag with Trim for X47 A
Root
25%
mid span
75%
tip
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-5
0
5
10
15
20x 10
-3
X
Zcam
be
r
Camber Distibution for Minimum Induced Drag with Trim for X47 B
Root
25%
mid span
75%
tip
Zcamber
Zcamber
Modeled via VLM
DV’s: AR, 𝜆, Sweep Angle to:
Minimize the total Drag
Maximize the Flutter Speed
While trimming the airplane at the cruise CL
Stable balance (negative CM𝛼) 2
46
810
12
0
20
40
60
800.011
0.0115
0.012
0.0125
ARSweep
CD
min
=1
CDmin
Modeled via VLM
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-3
-2.5
-2
-1.5
-1
-0.5
0Shape for the X47 B wing planform for minimum Induced Drag at the cruise CL + Trim
Without a contsraint on the volume to accomodate for thefuel, or on the root chord for the engine length
For: AR = 10, 𝜆 = 0.67, Sweep = 700, 𝐶𝑑𝑖 = 0.23 counts
Modeled via VLM , Matlab Optimization Toolbox
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
0Shape for the X47 B wing planform for minimum Induced Drag at the cruise CL + Trim
After adding a constraint on the root chord to accomodatefor the engine length + cabinIt looks pretty much like X47 A
AR = 5.8, 𝜆 = 0, Sweep = 16.7o, 𝐶𝐷𝑖 = 4.8 counts.
Modeled via VLM , Matlab Optimization Toolbox
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 10.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
Tw
ist
(de
g)
Twist Distibution for Minimum Induced Drag with Trim for the optimized X47 B
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-2
0
2
4
6
8
10x 10
-3
X
Zcam
ber
Camber Distibution for Minimum Induced Drag with Trim for the optimized X47 B
Root
25%
mid span
75%
tip
Twist (deg)
Zcamber
Modeled via VLM
X-47A is redesigned for optimum range operation
X-47B has 10 times the payload capacity of the X-47A
X-47B has better drag characteristics than the A
X-47B is neutrally stable, improving on the unstable A concept.
Artist Concept of the X-47B landing on an Aircraft Carrier.
www.strategypage.com
Technical Data and Published facts taken from.
1. Scaled Composites X-47A Facts and Figures, http://air-attack.com/page/28/X-47-Pegasus-UCAV-N.html.
2. X47B Facts and Figures. http://www.as.northropgrumman.com/products/nucasx47b/assets/X-47B-UCAS-Fact-Sheet.pdf. 4/19/2011.
3. A Vortex Lattice Method for the Mean Camber Shapes of Trimmed Non-Coplanar Planforms with Minimum Vortex Drag. By: John E. Lamar. NASA Report TN D-8090.
Artist Drawings and Photographs taken from:
1. X-47A. www.wikipedia.org.
2. X-47B www.northropgrumman.com.
3. Artist Concept of the X-47B landing on an Aircraft Carrier. www.strategypage.com.
4. X-47B in Landing Configuration www.technewsdaily.com.
5. X-47 Final Concept Art www.unmannedwarfare.webs.com.
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