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.