The JSF is a multi-role attack and fighter aircraft designed to replace the ageing F-16 Fighting Falcon, F/A-18 Hornet, A-10 Thunderbolt II, F-111 Raven, Sea Harrier and Harrier GR7 jets. It will complement the USAF's high-end F/A-22 Raptor air superiority fighter and the U.S. Navy's F/A-18E/F Super Hornet.

Design goals for the JSF include:

Stealth
Sensor integration to support precision ammunition
Low cost to provide adequate force structure for the armed forces
Low maintenance cost once deployed

The planes are being constructed in three different variants to suit the needs of various users -- a conventional take-off and landing aircraft (CTOL) for the US Air Force; a carrier based variant (CV) for the US Navy; and a short take-off and vertical landing (STOVL) aircraft for the US Marine Corps and the Royal Navy.
So far, as of late 2002, the program has stayed surprisingly close to its target cost of $28m for the cheapest Air Force variant. If the JSF eventually meets its cost targets, it will be the first U.S. military aircraft since World War II to do so.

The construction contract was awarded to Lockheed Martin (after Boeing's X-32 lost the bid) in October 2001, and the planes are expected to enter service in 2008.


Comments
Critics of the program maintain that the JSF suffers from ill-defined design goals; that it has insufficient internal fuel and weapon capacity to make a capable replacement for dedicated bombing aircraft; that its inability to supercruise limits it as an air defence platform, and that it is almost certain to suffer lengthy development delays and cost over-runs -- meaning that interim types will have to be purchased to fill the gap between the end of useful life of existing fleets and the introduction of the JSF. Several nations, however, already have sufficient confidence in the design to have committed substantial sums to become minority partners in the JSF manufacturing team.

The program's advocates see the JSF as an opportunity to break out of the decades-old pattern of U.S. military aircraft procurement: instead of a traditional per-service design approach, the JSF is being developed jointly by the Air Force, Navy and Marine Corps. This allows an estimated 80% commonality between the JSF variants for the different services, lowering aircraft and service costs. This follows to a degree the philosophy behind the SEPECAT Jaguar and Panavia Tornado international development programs, the latter being called a multi-role combat aircraft (or MRCA) prior to service entry. Additionally, JSF is the first U.S. aircraft program to consider cost as independent variable (CAIV). In earlier programs, the aircraft cost has been a dependent variable -- additional features have always increased the aircraft cost. Such design changes aren't being allowed during the JSF development.


Variants

F-35A: conventional land-based version for USAF
F-35B: STOVL for USMC, RAF and RN
F-35C: carrier-based version for USN

Characteristics

• Powerplant: Pratt & Whitney F135 turbofan rated at 15,876 kgf maximum thrust; military thrust classified, possibly about 12,000 kgf
• Size:
  • Length: 15.47 m
  • Height: 5.28 m
  • Wingspan: 10.05 m
  • Wing area: F-35A and F-35B: 42.7 m?; F-35C: 57.6 m?
• Weight:
  • Empty: 12,010 kg
  • Normal Takeoff: 19,000 kg (?)
  • Maximum: 22,680 kg
• Speed:
  • Maximum: Mach 1.7 at altitude,
• Ceiling: about 15 km.
• Range:
  • Operational radius: 1000 km (I assume this is without drop tanks, as including them would make it less stealthy)
  • Ferry: ? km
• Wing Loading: F-35A: 446 kg/m? at 19,000 kg
• Thrust/weight ratio: F-35A: 0.83 at 19,000 kg
• Armament:
  • 20 mm M61A-2 cannon, or 27 mm Mauser BK-27 cannon
  • 4 AAMs with a mix of AIM-132 ASRAAM and AIM-120 AMRAAM
• Cost: planned costs, in millions of 1994USD: F-35A: 28, F-35B: 35, F-35C: 38
• First flight: 2000
• In service date: expected to be 2008-2010
• Users: USA (USAF, USN, USMC); UK (RAF, RN); others

Text is available under the terms of the GNU Free Documentation License