program partners. It would be responsible for the forward cockpit and fuselage, as well as final assembly at Palmdale, California. Meanwhile, the wings and aft fuselage would be built by Boeing, with the center fuselage, weapons bays, tail and landing gear built by General Dynamics. Compared with its Northrop/McDonnell Douglas counterpart, the YF-22 has a more conventional design – its wings have larger control surfaces, such as full-span trailing edge, and, whereas the YF-23 had two tail surfaces, the YF-22 had four, which made it more maneuverable than its counterpart. Two examples of each prototype air vehicle (PAV) were built for the Demonstration-Validation phase: one with General Electric YF120 engines, the other with Pratt & Whitney YF119 engines. The YF-22 was given the unofficial name "Lightning II" after Lockheed's World War II-era fighter, the P-38 Lightning, which persisted until the mid-1990s when the USAF officially named the aircraft "Raptor". The F-35 later received the "Lightning II" name in 2006. The first YF-22 (PAV-1, serial number 87-0700, N22YF), with the GE YF120, was rolled out on 29 August 1990 and first flew on 29 September 1990, taking off from Palmdale piloted by David L. Ferguson. During the 18-minute flight, PAV-1 reached a maximum speed of and a height of , before landing at Edwards AFB. Following the flight, Ferguson said that the remainder of the YF-22 test program would be concentrated on "the manoeuvrability of the aeroplane, both supersonic and subsonic". The second YF-22 (PAV-2, s/n 87-0701, N22YX) with the P&W YF119 made its maiden flight on 30 October at the hands of Tom Morgenfeld. Operational history Evaluation During the flight test program, unlike the YF-23, weapon firings and high (60°) angle of attack (AoA, or high-alpha) flights were carried out on the YF-22. Though not a requirement, the aircraft fired AIM-9 Sidewinder and AIM-120 AMRAAM missiles from internal weapon bays. Flight testing also demonstrated that the YF-22 with its thrust vectoring nozzles achieved pitch rates more than double that of the F-16 at low-speed maneuvering. The first prototype, PAV-1, achieved Mach 1.58 in supercruise, while PAV-2 reached a maximum supercruise speed of Mach 1.43; maximum speed was in excess of Mach 2.0. Flight testing continued until 28 December 1990, by which time 74 flights were completed and 91.6 airborne hours were accumulated. Following flight testing, the contractor teams submitted proposals for ATF production. On 23 April 1991, the YF-22 was