Originally Posted By KS_Physicist:
The prototype YF-22 flew off against the prototype YF-23 in 1992, I remember watching a program on that flyoff on cable (Discovery channel?) in the early 1990s.
It was actually earlier than that!
F-22 Raptor History
The Advanced Tactical Fighter (ATF) program had its origins in numerous US Air Force air combat studies carried out in the late 1970s and early 1980s, when intelligence revealed the Soviets' early flight testing of the Fulcrum and Flanker. From the observed geometry of the airframes it was clear that both types would have the vortex lift performance to challenge existing US aircraft such as the F-15 in turning dogfights. Hoever, both Soviet fighters would be handicapped by their geometry in both supersonic maneuver and low observability performance.
In 1981, the Air Force developed a requirement for an Advanced Tactical Fighter as a new air superiority fighter. It would take advantage of the new technologies in fighter design on the horizon including composite materials, lightweight alloys, advanced flight control systems, higher power propulsion systems and stealth technology. Air Force leaders believed these new technologies would make aircraft like the F-15 and F-16 obsolete by the early 21st century.
The requirement for the F-22 was identified through the process described in Air Force Instruction (AFI) 10-601, Mission Needs and Operational Requirements Document and Procedures. During the early 1980s, the Air Force assessed its tactical capabilities against projected threats and determined that a mission deficiency would exist in the near future that could jeopardize the ability of the United States to ensure that its forces have the freedom of action to conduct operations against opposing forces. The Advanced Tactical Fighter Statement of Operational Need (November 1984) detailed this need, and Congressional funding and approval were received in 1985.
The ATF was to be the successor to the F-15, a long range air superiority fighter with the performance to kill any other tactical aircraft and the operating radius to threaten targets deep inside the USSR while flying from bases in Western Europe. This was to be achieved by the use of a highly integrated airframe/systems/propulsion design exploiting advanced aerodynamics, engines and stealth technology, the latter to delay an opponent's initial firing opportunity for as long as possible, and thus capitalise on the large Radar Cross section (RCS) of the Fulcrum and Flanker.
Modern weapon systems have traditionally contained many more specifications and greater detailed Statements of Work [SOW] than those of the past. Contrast the Army Signal Corps SOW for the Wright Brothers' heavier-than-air flying machine in 1908 to the Air Force SOW for the Advanced Tactical Fighter in 1986. Requirements in the 1908 SOW (e.g., be easily taken apart for transport in Army wagons and be capable of being reassembled for operation in an hour, carry 350 pounds for 125 miles, and maintain 40 miles per hours in still air) and other contract conditions were specified on one page. The requirements section in the 1986 SOW for the Air Force Advanced Tactical Fighter is 85 pages long with 300 paragraphs of requirements.
Subsequent to studies, an RFP was issued in July 1986. In October 1986, the Phase I Demonstration/Validation (Dem/Val) program was initiated, and the F-22's operational requirements, or Key Performance Parameters, were established. These parameters were documented in the System Operational Requirements document in 1987 and supported a Milestone I decision. Two contractor teams, Northrop/McDonnell-Douglas and Lockheed/Boeing/General Dynamics were selected in October 1986 for the initial 50 month demonstration/validation phase flyoff between the YF-22 and YF-23, the original designations of the F/A-22. The rollout of the prototypes was initially scheduled for mid 1989, but ongoing slippages delayed this. Both ATF prototypes were approximately 10% larger than the F-15 and both carry approximately twice the internal fuel of an F-15C, while both have about 50% more wing area at about 30% greater combat weight. As such both aircraft clearly illustrate the long range air superiority mission which was originally envisaged for the aircraft, penetrating deep into Soviet airspace to destroy air defence aircraft and to disrupt Soviet offensive air operations.
The F-22 team conducted a 54-month demonstration/ validation (dem/val) program. The effort involved the design, construction and flight testing of two YF-22 prototype aircraft. Two prototype engines, the Pratt & Whitney YF119 and General Electric YF120, also were developed and tested during the program. The dem/val program was completed in December 1990. Much of that work was performed at Boeing in Seattle, Lockheed (now known as Lockheed Martin) facilities in Burbank, Calif., and at General Dynamics' Fort Worth, Texas, facilities (now known as Lockheed Martin Tactical Aircraft Systems). The prototypes were assembled in Lockheed's Palmdale, Calif., facility and made their maiden flight from there. Since that time Lockheed's program management and aircraft assembly operations have moved to Marietta, Ga., for the EMD and production phases.
The System Operational Requirements document were updated on 01 March 1991. During the same time, the Advanced Tactical Fighter Full-Scale Development Environmental Assessment was prepared. Full-Scale Development has been subsequently redesignated as Engineering and Manufacturing Development (EMD).
In August 1991, the YF-22 was declared the winner. The F-22 passed milestone II in 1991.
"You can lead a horse to water, but you shouldn't have to stick your head up its ass and suck to make it drink."