Boeing's JSF X-32
The Boeing X-32 JSF short takeoff and vertical landing (STOVL) variant for the U.S. Marine Corps and U.K. Royal Navy employs a direct lift system for short takeoffs and vertical landings with uncompromised up-and-away performance.
Lockheed Martin's JSF X-35
The Lockheed Martin X-35 concept for the Marine and Royal Navy variant of the aircraft uses a shaft-driven lift-fan system to achieve Short-Takeoff/Vertical Landing (STOVL) capability. The aircraft will be configured with a Rolls-Royce/Allison shaft-driven lift-fan, roll ducts and a three-bearing swivel main engine nozzle, all coupled to a modified Pratt & Whitney F119 engine that powers all three variants.
|Type||strike fighter with Short-Takeoff/Vertical Landing (STOVL) capability|
|Contractor||two competing teams:
|Service||U.S. Air Force||U.S.
U.K. Royal Navy
|Variants||Conventional Takeoff and Landing (CTOL)||Short Takeoff and Vertical Landing (STOVL)||Carrier-based (CV)|
Pratt & Whitney F119-PW-100 derivative from F-22 Raptor
Alternate Engine: General Electric F120 core
|Empty Weight||~22,500 lbs||~24,000 lbs|
|Internal Fuel||15,000 lbs||16,000 lbs|
|Payload||13,000 lbs||17,000 lbs|
|Maximum Takeoff Weight||~50,000 lbs|
|Wingspan||36 feet||30 feet|
|Combat Radius||over 600 nautical miles|
U.K. Royal Navy
The Joint Strike Fighter (JSF) is a multi-role fighter optimized for
the air-to-ground role, designed to affordably meet
the needs of the Air Force, Navy, Marine Corps and allies, with improved survivability, precision engagement
capability, the mobility necessary for future joint operations and the reduced life cycle costs associated with tomorrow’s
fiscal environment. JSF will benefit from many of the same technologies developed for F-22 and will capitalize on commonality
and modularity to maximize affordability.
The 1993 Bottom-Up Review (BUR) determined that a separate tactical
aviation modernization program by each Service was
not affordable and canceled the Multi-Role Fighter (MRF) and Advanced Strike Aircraft (A/F-X) program. Acknowledging
the need for the capability these canceled programs were to provide, the BUR initiated the Joint Advanced Strike Technology
(JAST) effort to create the building blocks for affordable development of the next-generation strike weapons system. After a
review of the program in August 1995, DoD dropped the "T" in the JAST program and the JSF program has emerged from the
JAST effort. Fiscal Year 1995 legislation merged the Defense Advanced Research Projects Agency (DARPA) Advanced
Short Take-off and Vertical Landing (ASTOVL) program with the JSF Program. This action drew the United Kingdom (UK)
Royal Navy into the program, extending a collaboration begun under the DARPA ASTOVL program.
The JSF program will demonstrate two competing weapon system concepts
for a tri-service family of aircraft to affordably
meet these service needs:
The JSF concept is building these three highly common variants on the
same production line using flexible manufacturing
technology. Cost benefits result from using a flexible manufacturing approach and common subsystems to gain economies of
scale. Cost commonality is projected in the range of 70-90 percent; parts commonality will be lower, but emphasis is on
commonality in the higher-priced parts.
Key design goals of the JSF system include:
1)Survivability: radio frequency/infrared signature
reduction and on-board countermeasures to survive in the future
battlefield--leveraging off F-22 air superiority mission support
2) Lethality: integration of on- and off-board sensors to enhance delivery of current and future precision weapons
3) Supportability: reduced logistics footprint
and increased sortie generation rate to provide more combat power
earlier in theater
4) Affordability: focus on reducing cost of
developing, procuring and owning JSF to provide adequate force
JSF’s integrated avionics and stealth are intended to allow it to penetrate
surface-to-air missile defenses to destroy targets,
when enabled by the F-22’s air dominance. The JSF is designed to complement a force structure that includes other stealthy
and non-stealthy fighters, bombers, and reconnaissance / surveillance assets.
JSF requirements definition efforts are based on the principles of Cost
as an Independent Variable: Early interaction between
the warfighter and developer ensures cost / performance trades are made early, when they can most influence weapon system
cost. The Joint Requirements Oversight Council has endorsed this approach.
The JSF’s approved acquisition strategy provides for the introduction
of an alternate engine during Lot 5 of the production
phase, the first high rate production lot. OSD is considering several alternative implementation plans which would accelerate this
Lockheed Martin X-35's engine with vertical thrust position.
The focus of the program is producing effectiveness at an affordable
price—the Air Force’s unit flyaway cost objective is $28
million (FY94$). We anticipate Congress will fully fund JSF for FY98 (USAF, USN and DARPA Program Elements), with a
$15M plus-up for alternate engine risk reduction efforts. The Concept Demonstration Phase (CDP) was initiated in November
1996 with the selection of Boeing and Lockheed Martin. Both contractors are: (1) designing and building their concept
demonstration aircraft, (2) performing unique ground demonstrations, (3) developing their weapon systems concepts. First
operational aircraft delivery is planned for FY08.
The JSF is a joint program with shared acquisition executive responsibilities.
The Air Force and Navy each provide
approximately equal shares of annual funding, while the United Kingdom is a collaborative partner, contributing $200 million to
the CDP. CDP, also known as the Program Definition and Risk Reduction (PDRR) phase, consists of three parallel efforts
leading to Milestone II and an Engineering and Manufacturing Development (EMD) start in FY01: