The Lockheed Martin/Boeing F-22 Raptor is a single-seat, twin-engine fifth-generation supermaneuverable fighter aircraft that uses stealth technology. It was designed primarily as an air superiority fighter, but has additional capabilities that include ground attack, electronic warfare, and signals intelligence roles.[5] 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 Defense, Space & Security provides the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 during the years prior to formally entering USAF service in December 2005 as the F-22A. Despite a protracted and costly development period, the United States Air Force considers the F-22 a critical component of US tactical air power, and claims that the aircraft is unmatched by any known or projected fighter,[6] while Lockheed Martin claims that the Raptor’s combination of stealth, speed, agility, precision and situational awareness, combined with air-to-air and air-to-ground combat capabilities, makes it the best overall fighter in the world today.[7] Air Chief Marshal Angus Houston, former Chief of the Australian Defence Force, said in 2004 that the “F-22 will be the most outstanding fighter plane ever built.”[8]
The high cost of the aircraft, a lack of clear air-to-air combat missions because of delays in the Russian and Chinese fifth-generation fighter programs,[9] a US ban on Raptor exports, and the ongoing development of the planned cheaper and more versatile F-35 resulted in calls to end F-22 production.[N 1] In April 2009 the US Department of Defense proposed to cease placing new orders, subject to Congressional approval, for a final procurement tally of 187 Raptors.[11] The National Defense Authorization Act for Fiscal Year 2010 lacked funding for further F-22 production.
Characteristics
F-22 Raptor flying with its F119-PW-100engines on full afterburner
The F-22 Raptor is a fifth generation fighter that is considered a fourth-generation stealth aircraft by the USAF.[115] Its dual afterburning Pratt & Whitney F119-PW-100 turbofans incorporate pitch axis thrust vectoring, 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.[116] Maximum speed, without external weapons, is estimated to be Mach 1.82 in supercruise mode,[117] 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.[118] With afterburners, it is “greater than Mach 2.0” (1,317 mph, 2,120 km/h). Former Lockheed F-22 chief test pilot Paul Metz stated that the Raptor has a fixed inlet; the absence of variable intake ramps typically limits speeds to approximately Mach 2.0. Metz has also stated that the F-22 has a greater climb rate 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 (the F-22 has a ratio closer to 1:1).[119] The US Air Force claims that the Raptor cannot be matched by any known or projected fighter types,[6] and Lockheed Martin claims: “the F-22 is the only aircraft that blends supercruise speed, super-agility, stealth and sensor fusion into a single air dominance platform.”[120]
F-22 Raptor flight demonstration video
The ability of airframes to withstand both stress and heat is a major design factor, thus the F-22 makes use of many polymers; however, as some of the materials are a significant health risk to personnel, technicians require protective equipment such as eye protection, respirators and gloves to work upon the aircraft.[121] The use of internal weapons bays allows the aircraft to maintain a comparatively higher performance while carrying a heavy payload over many other aircraft due to a lack of drag from external stores. It is one of only a few of aircraft that can supercruise, sustained supersonic flight without the use of afterburners, lowering fuel usage. The F-22 can intercept time-critical or rapidly moving targets that a subsonic aircraft would not have the speed to follow and an afterburner-dependent aircraft would lack fuel to reach.[122]
The F-22 is highly maneuverable, at both supersonic and subsonic speeds. It is extremely departure-resistant,[123] enabling it to remain controllable at extreme pilot inputs. The Raptor’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,[119] and the Kulbit.[119] The F-22 is also capable of maintaining a constant angle of attack of over 60°, yet still having some control of roll.[119][124] 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 against other US fighters and 4th/4.5th generation fighters.[125]
The F-22’s ground attack capabilities are minimal. It has no forward looking infrared, Laser designator or laser spot tracker and it cannot carry an external pod to provide these capabilities. Its ability to locate ground targets with radar is still under development and it can only carry a very modest bomb and fuel load in a stealthy configuration.[citation needed]
LINK-http://http://www.youtube.com/watch?v=8dly6DQ0fNA
PIYUSH YADAV 