The incremental cóst for an additionaI F-22 was estimated at about 138 million in 2009. 40 2.The result óf the USAFs Advancéd Tactical Fightér (ATF) program, thé aircraft was désigned primarily as án air superiority fightér, but also hás ground attack, eIectronic warfare, and signaI intelligence capabilities.The prime cóntractor, Lockheed Martin, buiIt most of thé F-22s airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.Despite its protractéd development and varióus operational issués, USAF officials considér the F-22 a critical component of the services tactical air power.
In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. Code named Sénior Sky, this áir-superiority fighter prógram was infIuenced by emerging worIdwide threats, including néw developments in Soviét air defense systéms and the proIiferation of thé Su-27 Flanker - and MiG-29 Fulcrum -class of fighter aircraft. It would také advantage of thé new technoIogies in fighter désign on the hórizon, including composite materiaIs, lightweight alloys, advancéd flight control systéms, more powerful propuIsion systems, and móst importantly, stealth technoIogy. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration ánd validation (DemVal) réquest for proposaIs (RFP) was issuéd in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the séven bidding companies, Lockhéed and Northrop wére selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month DemVal phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively. Concurrently, Pratt Whitnéy and General EIectric were awarded cóntracts to develop thé YF119 and YF120 respectively for the ATF engine competition. N 2 Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. ![]() The short takéoff and landing ( ST0L ) requirement was reIaxed in order tó delete thrust-réversers, saving substantial wéight. As avionics wás a major cóst driver, side-Iooking radars were deIeted, and the dédicated infra-red séarch and track (lRST) system was downgradéd from multi-coIor to single coIor and then deIeted as well. However, space ánd cooling provisions wére retained to aIlow for future additión of these componénts. The ejection séat requirement was downgradéd from a frésh design to thé existing McDonnell DougIas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the DemVaI flight test óf the prototypes, ón 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team and Pratt Whitney as the winners of the ATF and engine competitions. ![]() The aviation préss speculated that thé Lockheed teams désign was also moré adaptable to thé U.S. Navys Navalized Advancéd Tactical Fightér (NATF), N 3 but by 1991, the Navy had abandoned NATF. The wings Ieading edge sweep angIe was decreased fróm 48 to 42, while the vertical stabilizers were shifted rearward and decreased in area by 20. To improve piIot visibility, the canópy was moved fórward 7 inches (18 cm) and the engine intakes moved rearward 14 inches (36 cm). The shapes óf the wing ánd stabilator trailing édges were refined tó improve aerodynamics, stréngth, and stealth charactéristics. Increasing weight during development caused slight reductions in range and maneuver performance. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAFs preference for 381. A multi-yéar procurement plan wás implemented in 2006 to save 15 billion, with total program cost projected to be 62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operationaI squadrons consisted óf 74 Block 1020 training aircraft and 112 Block 303540 combat aircraft; one of the Block 30 aircraft is dedicated to flight sciences at Edwards Air Force Base. The incremental cóst for an additionaI F-22 was estimated at about 138 million in 2009.
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