In 1981 the United States Air Force (USAF) developed a requirement for a new air superiority fighter, the Advanced Tactical Fighter (ATF), to replace the capability of the F-15 Eagle. ATF was a demonstration and validation program undertaken by the USAF to develop a next-generation air superiority fighter to counter emerging worldwide threats, including development and proliferation of Soviet-era Su-27 "Flanker"-class fighter aircraft. It was envisaged that the ATF would incorporate emerging technologies including advanced alloys and composite materials, advanced fly-by-wire flight control systems, higher power propulsion systems, and low-observable/stealth technology.
A request for proposal (RFP) was issued in July 1986, and two contractor teams, Lockheed/Boeing/General Dynamics and Northrop/McDonnell Douglas were selected in October 1986 to undertake a 50-month demonstration/validation phase, culminating in the flight test of two prototypes, the YF-22 and the YF-23.
On 23 April, 1991 the USAF ended the design and test-flight competition by announcing Lockheed's YF-22 as the winner. It was anticipated at the time that 650 aircraft would be ordered.
Into production...
The first production F-22 was delivered to Nellis Air Force Base, Nevada, on 14 January, 2003 and "Dedicated Initial Operational Test and Evaluation" commenced on 27 October, 2004. By 2004, 51 Raptors were in service.
The first crash of a production F-22 occurred during take-off at Nellis Air Force Base on 20 December, 2004, in which the pilot ejected safely prior to impact. The crash investigation revealed that a brief interruption in power during an engine shutdown prior to flight caused a malfunction in the flight-control system; consequently, the technical data for the aircraft has been amended to avoid a recurrence of this problem.
In August 2007, the United States Air Force signed a $5 billion, multi-year contract with Lockheed Martin that will extend production to 2011, and as of 2008, F-22 Raptors are being procured at the rate of 20 per year.
In a ceremony on 29 August, 2007, Lockheed Martin reached its "100th F-22 Raptor" milestone, delivering aircraft 05-4100.
Proposed foreign purchases...
Unlike many other tactical fighters, the opportunity for export is currently non-existent because the export sale of the F-22 is barred by federal law. There was a time in the 1970s when the then-new F-16 was similarly restricted. However, regardless of restrictions, very few allies would even be considered for export sale because the F-22 is such a sensitive and expensive system. Most current customers for U.S. fighters are either acquiring earlier designs like the F-15 or F-16, or else are waiting to acquire the F-35, which contains much of the F-22's technology but is designed to be cheaper and more flexible.
The Japanese government reportedly showed some interest in buying F-22As in its Replacement-Fighter program for its Air Self-Defense Force (JASDF). In such an event, it would most likely involve a "watered-down" export variant while still retaining most of its advanced avionics and stealth characteristics. However, such a proposal would still need approval from the Pentagon, State Department and Congress.
Israeli Air Force (IAF) chief procurement officer Brigadier-General Ze'ev Snir said that, "The IAF would be happy to equip itself with 24 F-22s, but the problem at this time is the US refusal to sell the aircraft, and its $200 million price tag."
Some Australian politicians and defense commentators have proposed that Australia purchase F-22s instead of the F-35. In 2006, the Australian Labor Party supported this proposal on the grounds that the F-22 is a proven, highly capable aircraft, while the F-35 is still under development. However, the Howard government ruled out purchase of the F-22, on the grounds that it is unlikely to be released for export, and does not have sufficient ground/maritime strike capacity. This assessment was supported by the Australian Strategic Policy Institute, which claimed that the F-22 "has insufficient multi-role capability at too high a price." The ASPI analysis was, however, criticized by Air Power Australia.
The US Congress upheld the ban on F-22 Raptor foreign sales during a joint conference on September 27th, 2006. After talks in Washington in December 2006, the US DoD reported the F-22 would not be available for foreign sale.
Following the victory of the Australian Labor Party in the 2007 national election, the new government ordered a review of plans to procure the F-35 and F/A-18E/F Super Hornet. This review will include an evaluation of the F-22's suitability for Australia; moreover, Defence Minister Joel Fitzgibbon has stated: "I intend to pursue American politicians for access to the Raptor". In February 2008, U.S. Defense Secretary Robert Gates said he had no objection to sale of the Raptor to Australia, but Congress would have to change the law.
Characteristics...
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 resulting in a compression stall, 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.
Airframe...
Several small design changes were made from the YF-22A prototype to the production F-22A. The swept-back angle on the wing's leading edge was decreased from 48 degrees to 42 degrees, while the vertical stabilizer area was decreased 20%. To improve pilot visibility, the canopy was moved forward 7 inches (178 mm) and the engine intakes were moved rearward 14 inches (356 mm). The shape of the wing and stabilator trailing edges was refined to improve aerodynamics, strength, and stealth characteristics.
Stealth...
Although several recent Western fighter aircraft are less detectable on radar than previous designs using techniques such as radar absorbent material-coated S-shaped intake ducts that shield the compressor fan from reflecting radar waves, the F-22 design placed a much higher degree of importance on low observance throughout the entire spectrum of sensors including radar signature, visual, infrared, acoustic, and radio frequency.
The stealth of the F-22 is due to a combination of factors, including the overall shape of the aircraft, the use of radar absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. However, reduced radar cross section is only one of five facets that designers addressed to create a stealth design in the F-22. The F-22 has also been designed to disguise its infrared emissions to make it harder to detect by infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Designers also made the aircraft less visible to the naked eye, and controlled radio and noise emissions. The Raptor has an under bay carrier made for hiding heat from missile threats, like surface-to-air missiles.
The F-22 apparently relies less on maintenance-intensive radar absorbent material and coatings than previous stealth designs like the F-117. These materials caused deployment problems due to their susceptibility to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangers, the F-22 can undergo repairs on the flight line or in a normal hangar. Furthermore, the F-22 has a warning system (called "Signature Assessment System" or "SAS") which presents warning indicators when routine wear-and-tear have degraded the aircraft's radar signature to the point of requiring more substantial repairs. The exact radar cross section of the F-22 remains classified.
Operational History...
Intended to be the leading American advanced tactical fighter in the early part of the 21st century, the Raptor is an expensive fighter with an incremental cost of about US$138 million per unit. The number of aircraft to be built has dropped to 183, down from the initial requirement of 750. Part of the reason for the decrease in the requirement is that the F-35 Lightning II uses much of the technology used on the F-22, but at a much more affordable price. To a large extent the cost of these technologies is only lower for the F-35 because they have already been developed for the F-22.
YF-22 "Lightning II"...
The prototype YF-22 won a fly-off competition against the Northrop/McDonnell-Douglas YF-23 for the Advanced Tactical Fighter contract. In April 1992 during flight testing after contract award, test pilot Tom Morgenfeld escaped without injury when the first YF-22 prototype that he was flying crashed while landing at Edwards Air Force Base in California. The cause of the crash was found to be a flight control software error that failed to prevent a pilot-induced oscillation.
The YF-22 was a developmental aircraft that led to the F-22; however, there are significant differences between the YF-22 and the F-22. Relocation of cockpit, structural changes, and many other smaller changes exist between the two types. The two are sometimes confused in pictures, often at angles where it is difficult to see certain features. For example, there are some F-22 with pitot booms which some think are only found on the YF-22.
The YF-22 was originally given the unofficial name "Lightning II", after the WWII fighter P-38, by Lockheed, which persisted until the mid-1990s when the USAF officially named the aircraft "Raptor". For a short while, the aircraft was also dubbed "SuperStar" and "Rapier". The F-35 later received the Lightning II name on July 7th 2006.
F-22 Raptor to F/A-22 and back again...
The production model was formally named F-22 "Raptor" when the first production-representative aircraft was unveiled on 9 April, 1997 at Lockheed-Georgia Co., Marietta, Georgia. First flight occurred on 7 September, 1997.
In September 2002, Air Force leaders changed the Raptor’s designation to F/A-22. The new designation, which mimicked that of the Navy’s F/A-18 Hornet, was intended to highlight plans to give the Raptor a ground-attack capability amid intense debate over the relevance of the expensive air-superiority jet. This was later changed back to simply F-22 on 12 December, 2005. On 15 December, 2005, the F-22A entered service.
Recent Developments...
In 2006, the Raptor's development team, composed of Lockheed Martin and over 1,000 other companies, plus the United States Air Force, won the Collier Trophy, American aviation's most prestigious award. The U.S Air Force will acquire F-22s that are to be divided among seven active duty combat squadrons, and jointly flown and maintained by three integrated Reserve and Air National Guard squadrons.
During Exercise Northern Edge in Alaska in June 2006, 12 F-22s of the 94th FS downed 108 adversaries with no losses in simulated combat exercises. In two weeks of exercises, the Raptor-led Blue Force amassed 241 kills against two losses in air-to-air combat, and neither Blue Force loss was an F-22.
This was followed with the Raptor's first participation in a Red Flag exercise. 14 F-22s of the 94th FS supported attacking Blue Force strike packages as well as engaging in close air support sorties themselves in Red Flag 07-1 between February 3rd and February 16th 2007. Against designed superior numbers of Red Force Aggressor F-15s and F-16s, it established air dominance using eight aircraft during day missions and six at night, reportedly defeating the Aggressors quickly and efficiently, even though the exercise rules of engagement allowed for four to five Red Force regenerations of losses but none to Blue Force. Further, no sorties were missed because of maintenance or other failures, and only one Raptor was adjudged lost against the virtual annihilation of the defending force. When their ordnance was expended, the F-22s remained in the exercise area providing electronic surveillance to the Blue Forces.
While attempting its first overseas deployment to the Kadena Air Base in Okinawa, Japan, on 11 February, 2007, a group of six Raptors flying from Hickam AFB experienced multiple computer crashes coincident with their crossing of the 180th meridian of longitude (the International Date Line). The computer failures included at least navigation (completely lost) and communication. The fighters were able to return to Hawaii by following their tankers in good weather. The error was fixed within 48 hours and the F-22s continued their journey to Kadena.
On 30 April 2007, the National Museum of the Air Force announced that EMD Raptor 91-4003 would be put on display later in 2007 in the space being occupied by the YF-22. The Museum publicly unveiled its Raptor 91-4003 display on January 18th, 2008.
In 2007, tests carried out by Northrop Grumman, Lockheed Martin, and L-3 Communications enabled the AESA system of a Raptor to act like a WiFi access point, able to transmit data at 548 Megabit/sec and receive at Gigabit speed; far faster than the current Link 16 system used by US and allied aircraft, which transfers data at just over 1 Megabit/sec.
On November 22nd, 2007, F-22A Raptors of the 90th Fighter Squadron performed their first intercept of two Russian Tu-95MS 'Bear-H' bombers in Alaska. This was the first time that F-22s had been called to support a NORAD mission.
On December 12th, 2007, Gen. John D.W. Corley, commander of Air Combat Command, officially declared the F-22s of the integrated active duty 1st Fighter Wing and Air National Guard 192nd FW fully operational, three years after the first Raptor arrived at Langley Air Force Base. This was followed from April 13th to April 19th, 2008 by an Operational Readiness Inspection (ORI) of the integrated wing in which it received an "excellent" rating in all categories while scoring a simulated kill-ratio of 221-0.
General Characteristics
- Crew: 1
- Length: 62 ft 1 in (18.90 m)
- Wingspan: 44 ft 6 in (13.56 m)
- Height: 16 ft 8 in (5.08 m)
- Wing area: 840 ft² (78.04 m²)
- Airfoil: NACA 64A?05.92 root, NACA 64A?04.29 tip
- Empty weight: 31,670 lb (14,365 kg)
- Loaded weight: 55,352 lb (25,107 kg)
- Max takeoff weight: 80,000 lb (36,288 kg)
- Powerplant: 2× Pratt & Whitney F119-PW-100 Pitch Thrust vectoring turbofans, 35,000+ lb (156+ kN) each
- Maximum speed:
Supercruise: Mach 1.72 (1,140 mph, 1,825 km/h) at altitude
- Range: 1,600 nmi (1,840 mi, 2,960 km) with 2 external fuel tanks
- Combat radius: 410 nmi (471 mi, 759 km)
- Ferry range: 2,000 mi (1,738 nmi, 3,219 km)
- Service ceiling: 65,000 ft (19,812 m)
- Wing loading: 66 lb/ft² (322 kg/m²)
- Thrust/weight: 1.26
- Maximum g-load: -3.5/+9.5 g
- Guns: 1× 20 mm (0.787 in) M61A2 Vulcan gatling gun in starboard wing root, 480 rounds
- Air to air loadout:
2× AIM-9 Sidewinder
- Air to ground loadout:
2× AIM-9 Sidewinder and one of the following:
2× 1,000 lb (450 kg) JDAM or
2× Wind Corrected Munitions Dispensers (WCMDs) or
8× 250 lb (110 kg) GBU-39 Small Diameter Bombs
Note: It is estimated that the internal bays can carry about 2,000 lb (910 kg) worth of bombs, and/or missiles. Four external hardpoints can be fitted to carry weapons or fuel tanks, each with a capacity of about 5 000 lb (2268 kg).
- RWR (Radar warning receiver): 250 nmi (463 km) or more
- Radar: 125-150 miles (200-240 km) against 1 m² targets (estimated range).
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