The Lockheed Martin/Boeing F-22 Raptor is an American fighter aircraft that uses stealth technology. It is primarily an air superiority fighter, but has multiple capabilities that include ground attack, electronic warfare, and signals intelligence roles. The United States Air Force considers the F-22 a critical component of the U.S. strike force.
Faced with a protracted development period, the aircraft was variously designated F-22 and F/A-22 during the three years before formally entering US Air Force service in December 2005, as the F-22A. Lockheed Martin Aeronautics is the prime contractor and is responsible for the majority of the airframe, weapon systems and final assembly of the F-22. Program partner Boeing Integrated Defense Systems provides the wings, aft fuselage, avionics integration, and all of the pilot and maintenance training systems.
The F-22 is claimed by several sources to be the world’s most effective air superiority fighter. The US Air Force claims that the F-22 cannot be matched by any known or projected fighter aircraft. Chief of the Australian Defence Force, then-Air Marshal Angus Houston, said in 2004 that the "F-22 will be the most outstanding fighter plane ever built."
The F-22 is a fifth-generation fighter that is considered a fourth-generation stealth aircraft by the USAF.Its dual afterburning Pratt & Whitney F119-PW-100 turbofans incorporate thrust vectoring, but in the pitch axis only, with a range of ±20 degrees. The maximum thrust is classified, though most sources place it at about 35,000 lbf (156 kN) per engine. Maximum speed, without external weapons, is estimated to be Mach 1.72 in supercruise mode; as demonstrated by General John P. Jumper, former US Air Force Chief of Staff, when his Raptor exceeded Mach 1.7 without afterburners on 13 January 2005.With afterburners, it is "greater than Mach 2.0" (1,317 mph, 2,120 km/h), according to Lockheed Martin; however, the Raptor can easily exceed its design speed limits, particularly at low altitudes, with max-speed alerts to help prevent the pilot from exceeding them. Former Lockheed Raptor chief test pilot Paul Metz stated that the Raptor has a fixed inlet; but while the absence of variable intake ramps may theoretically make speeds greater than Mach 2.0 unreachable, there is no evidence to prove this. Such ramps would be used to prevent engine surge, but the intake itself may be designed to prevent this. Metz has also stated that the F-22 has a top speed greater than 1,600 mph (Mach 2.42) and its climb rate is faster than the F-15 Eagle due to advances in engine technology, despite the F-15's thrust-to-weight ratio of about 1.2:1, with the F-22 having a ratio closer to 1:1. The US Air Force claims that the F-22A cannot be matched by any known or projected fighter.
The true top-speed of the F-22 is largely unknown to the general public, as engine power is only one factor. The ability of the airframe to withstand the stress and heat from friction is a further, key factor, especially in an aircraft using as many polymers as the F-22. However, while some aircraft are faster on paper, the internal carriage of its standard combat load allows the aircraft to reach comparatively higher performance with a heavy load over other modern aircraft due to its lack of drag from external stores. It is one of only a handful of aircraft that can sustain supersonic flight without the use of afterburner augmented thrust (and its associated high fuel usage). This ability is called supercruise.
The F-22 is highly maneuverable, at both supersonic and subsonic speeds. The F-22's thrust vectoring nozzles allow the aircraft to turn tightly, and perform extremely high alpha (angle of attack) maneuvers such as the Herbst maneuver (or J-turn), Pugachev's Cobra, and the Kulbit, though the J-Turn is more useful in combat.The F-22 is also capable of maintaining a constant angle of attack of over 60°, yet still having some control of roll. During June 2006 exercises in Alaska, F-22 pilots demonstrated that cruise altitude has a significant effect on combat performance, and routinely attributed their altitude advantage as a major factor in achieving an unblemished kill ratio.
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