Joint Strike FighterF-35C

Soumit BanerjeeMichael LaPierre

Sean Tzeng

F-35 Purpose• The JSF is a fighter platform with a variant design for

all branches of the military.• 3 production versions are planned:

1) F-35A: CTOL variant to replace F-16 & A-102) F-35B: STOVL variant to replace AV-8B, F/A-18 C/D, Sea

Harrier, and GR-7. Will complement F-223) F-35C: CV variant. Our analysis will focus on this version of

the JSF

• The F-35C model was designed with larger wings andtail control surfaces for carrier operations

• It is also strengthened structurally to handle catapultlaunches and arrested landings

Information courtesy of www.jsf.mil

F-35C Mission Roles

• The F-35C is the carrier based variant of the JSF,designed and built for STOL capability.

• It is a multi-role, stealthy, survivable fighter designed tocomplement the F/A-18 E/F.

• AI: Medium level attacks using precision guided, freefallor retarded bombs

• CAS: Air action against hostile targets, in closeproximity to friendly forces

• Fleet defense: Aerial patrolling of ships

F-35C OverviewFirst flight: 02/12/2001

Crew: 1

Data for F-35C available “Jane’s All the World’s Aircraft 2004-2005”Picture available www.jsf.mil

Mach 1.8Max speed at altitude

20,000+Payload (lbs)

66,850MTOGW (lbs)

30,618Wempty (lbs)

620.00Reference Area (ft2)

15.25Tailscrape angle (deg)

28.3Tailspan (ft)

15.5Height (ft)

51.4Length (ft)

29.8Folded span (ft)

43.0Wingspan (ft)

Propulsion• Pratt & Whitney F135

• Thrust = 40,000 lbs

• T/Wmax = 0.598

• TSFC was unavailable

F-35B STOVL lifting fan

PW F135

Pictures courtesy of www.pratt-whitney.com and www.rollsroyce.com

Weights

F-35B STOVL variant on display at NASM Dulles Airport

0.29Wfuel/TOGW

0.3Wpayload/TOGW

107.82W/Smax (lb/ft2)

66,850MTOGW (lbs)

19,624Wfuel (lbs)

20,000+Max Payload(lbs)

30,618Wempty (lbs)

VLMpc vs. AVL

AVL available from http://raphael.mit.edu/avl/ VLMpc available from http://www.aoe.vt.edu/~mason/Mason_f/MRsoft.html

0.07070

0.06214

CL_

(per degree)

-12.99

-10.30

Static Margin(% mac)

-12.9929.6916.9331.44AVL

-10.3029.2416.9331.44VLMpc

Static Margin(% mac)

Neutral Point(ft. from nose)

MAC(ft)

Center ofGravity

(ft. from nose)

Method ofAnalysis

CG Estimate done using landing gear locations and Kirschbaum’s suggestions

Spanload Distributions• Obtained from VLMpc

• Load split:67% wing-body 33% tail

-1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 00

0.05

0.1

0.15

0.2

0.25

0.3

0.35Spanload distribution at CL = 0.323

2y/b

Spanload data

-1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 00

0.2

0.4

0.6

0.8

1

1.2

1.4Spanload Coefficient distribution

2y/b

Spanload data

Flat Wing Spanload coefficient Flat wing Spanload at cruise

CL Distribution

-1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0

0.8

1

1.2

1.4

1.6

1.8

2

2y/b

Cl/CL

Cl/CL versus 2y/b

FRICTION Analysis

0.324CL cruise

14.47L/Dmax

0.0119cD0

0.6M

30,000 ftAltitude

• Wetted area is estimated of the figure of the airplane• Swet = 2589.63 ft2

0.2 0.3 0.4 0.5 0.6 0.7 0.80.01

0.0105

0.011

0.0115

0.012

0.0125

0.013

0.0135

0.014

0.0145

0.015

Mach number

Cd0

Plot of Cd0 vs Mach number

h = 30K fth = 35K fth = 40K ft

STOVL Video

Video Courtesy of www.jsf.mil

References

• http://www.deagel.com

• http://www.raf.mod.uk

• http://www.airforce-technology.com/projects/jsf/specs.html

• www.jsf.mil

• Jane’s All The World’s Aircraft: 2004-2005

Relevant Equations• (L/D)max = 14.47 (FRICTION)

• Rangemax = 1480 km– TSFC Data unavailable from Pratt

• CL Cruise = 0.324

• CL max = 3 – 3.5?– Raymer1 suggests that STOL

aircraft such as carrier-based

fighters require a max lift

coefficient upwards of 3.0. It is

our estimation that with the F-35C’s

high lift devices it could achieve

slightly more.

1 – Raymer, Daniel. “Aircraft Design: A Conceptual Approach”, 3rd Edition