F-22A development
By 1990 Lockheed Martin, teamed with Boeing and General Dynamics, had built and flown the demonstration prototype aircraft, designated YF-22. The first F-22 fighter aircraft was unveiled in April 1997 and was given the name Raptor.
In September 2002, the USAF decided to redesignate the aircraft F/A-22 to reflect its multi-mission capability in ground attack as well as air-to-air roles. The aircraft's designation was changed again to F-22A when it achieved initial operating capability (IOC) in December 2005.
The decision to proceed to low-rate initial production (LRIP) was authorised in August 2001 and Lockheed Martin delivered 49 aircraft under LRIP contracts. Initial operational test and evaluation began in April 2004 and was successfully completed in February 2005.
A further 60 Raptors were ordered in July 2007, bringing total ordered to 183, with production to 2011. The USAF has a total requirement of 381 aircraft but funding may not be made available for more than 183. By July 2008, 122 aircraft had been delivered.
The first operational wing of F-22A Raptors was Langley AFB in Virginia with a fleet of 40 aircraft. Elmendorff AFB, Alaska, became the second in August 2007 and Holloman AFB, New Mexico the third in June 2008. Operational Raptors will also be based at Hickam AFB Hawaii.
The F-22 achieved full operational capability in December 2007.
In February 2007, 12 F-22 aircraft began the first overseas deployment of the fighter at Kadena Air Base in Japan. The aircraft returned in May 2007.
During flight tests, the F-22A has demonstrated the ability to 'supercruise', flying at sustained speeds of over Mach 1.5 without the use of afterburner.
Lockheed Martin has put forward proposals for a fighter-bomber version of the F-22, the FB-22, which will have larger delta wings, longer range and the ability to carry an external weapons payload of 4,500kg and total weapons payload of 15,000kg.
Raptor design
The F-22 construction is 39% titanium, 24% composite, 16% aluminium and 1% thermoplastic by weight. Titanium is used for its high strength-to-weight ratio in critical stress areas, including some of the bulkheads, and also for its heat-resistant qualities in the hot sections of the aircraft.
Carbon-fibre composites have been used for the fuselage frame, the doors, intermediate spars on the wings, and for the honeycomb sandwich construction skin panels.
F-22 cockpit
The cockpit is fitted with hands-on throttle and stick control (HOTAS). The cockpit has six color liquid crystal displays. The Kaiser Electronics projection primary multifunction display provides a plan view of the air and ground tactical situation including threat identity, threat priority and tracking information.
Two displays provide communication, navigation, identification and flight information. Three secondary displays show air and ground threats, stores management and air threat information.
A BAE Systems head-up display (HUD) shows target status, weapon status, weapon envelopes and shoot cues. A video camera records data on the HUD for post-mission analysis.
Weapons
A variant of the M61A2 Vulcan cannon is installed internally above the right air intake. The General Dynamics linkless ammunition handling system holds 480 rounds of 20mm ammunition and feeds the gun at a rate of 100 rounds a second.
The F-22 has four hardpoints on the wings, each rated to carry 2,270kg, which can carry AIM-120A AMRAAM or external fuel tanks. The Raptor has three internal weapon bays. The main weapons bay can carry six AMRAAM AIM-120C missiles or two AMRAAM and two 1,000lb GBU-32 joint direct attack munition (JDAM).
The bay is fitted with the EDO Corp. LAU-142/A AVEL AMRAAM vertical ejection launcher which is a pneumatic-ejection system controlled by the stores management system. Raytheon AMRAAM air-to-air missile is an all-weather short- to medium-range radar-guided fire-and-forget missile, with a range of 50nm. The side bays can each be loaded with one Lockheed Martin / Raytheon AIM-9M or AIM-9X Sidewinder all-aspect short-range air-to-air missile.
The GPS-guided, Boeing small diameter bomb (SDB) is being integrated on the F/A-22 in February 2007. Eight SDBs can be carried with two AMRAAM missiles.
Radar
The AN/APG-77 radar has been developed for the F-22 by the Electronic Sensors and Systems Division of Northrop Grumman and Raytheon Electronic Systems. The radar uses an active electronically scanned antenna array of 2,000 transmitter / receive modules, which provides agility, low radar cross-section and wide bandwidth. Deliveries of the AN/APG-77 began in May 2005.
Countermeasures
The aircraft's electronic warfare system includes a radar warning receiver and a BAE Systems information & electronic warfare systems (IEWS) (formerly Lockheed Martin Sanders) missile launch detector.
Navigation and communications
"The F-22 advanced tactical fighter is powered by two Pratt and Whitney F119-100 engines."
The TRW CNI communications, navigation and identification system includes an intra-flight datalink, joint tactical information distribution system (JTIDS) link and an identification friend or foe (IFF) system.
Boeing is responsible for mission software and avionics integration. The aircraft has a Northrop Grumman (formerly Litton) LTN-100G laser gyroscope inertial reference, a global positioning system and a microwave landing system.
Engine
The F-22 is powered by two Pratt and Whitney F119-100 engines. The F119-100 is a low bypass after-burning turbofan engine providing 156kN thrust. The F119 is the first fighter aircraft engine equipped with hollow wide chord fan blades which are installed in the first fan stage.
Thrust vectoring is controlled by a Hamilton Standard dual redundant full authority digital engine control (FADEC). The FADEC is integrated with the flight control computers in the BAE Systems flight controls vehicle management system.
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