Science Fair Project Encyclopedia
Intended to be the leading United States advanced tactical fighter in the early part of the 21st century, the Raptor is certainly the most expensive fighter ever. The Pentagon concluded in 2004 that the total development and production cost of the currently planned 279 aircraft will come to $71.7 billion, or $256.9 million per plane. (Some say the estimate should be somewhat lower because some research and development support the F-35 Joint Strike Fighter as well.)
The prototype YF-22, later designated as the "Raptor," 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, the first YF-22A prototype crashed while landing at Edwards Air Force Base in California. The test pilot, who was blamed for the crash, was not injured.
The first flight of the production-representative F/A-22 Raptor occurred on September 7, 1997 at Lockheed-Georgia Co., Marietta, Georgia. The first production F/A-22 was delivered to Nellis Air Force Base, Nevada, on January 14, 2003. As of late 2004, 51 Raptors are in service, with 22 more ordered under fiscal year 2004 funding. F/A-22 Initial Operational Capability (IOC) occurred on October 27, 2004. The first production F/A-22 crash occurred at Nellis Air Force Base on December 20, 2004, during takeoff. The pilot ejected safely moments before impact. The accident is still under investigation but investigators are pointing to a mechanical malfunction, not pilot error.
The dual Pratt & Whitney F119-PW-100 turbofans with afterburners incorporate supercruise and thrust vectoring. Thrust vectoring is in the pitch axis only, with a range of ± 20 degrees. The maximum thrust is classified, though most sources place it at about 39,000 lbf (173 kN). Maximum speed is Mach 1.58 in supercruise mode; with afterburners, "approximately Mach 2.0+" (2,120 km/h). The absence of variable intake ramps may make Mach 2.0+ unreachable. It has been speculated that the computerized flight control system (FLCS) limits the top speed to prevent the skin of the aircraft from deforming at high temperatures. Avionics include Raytheon and Northrop Grumman AN/APG-77 Active Electronically Scanned Array (AESA) radar.
The United States Air Force originally planned an order of 750 ATFs, with production from 1994. Following the 1990 Major Aircraft Review, production was to begin in 1996 for a total of 648 aircraft. By 1994 the figure stood at 442 planes for service entry in 2003/2004. A DoD report in 1997 stated that 339 was the final number. Currently there is significant debate over the exact number of units affordable, though in 2003 the USAF said that it could buy 277 given a $43 billion cost limit. In 2005, for the fiscal year 2006, under further DoD cost cutting measures, is forecasting the number of aircraft procured at 180 saving an additional $15 billion but raising the per unit cost. Congress must approve the new proposal that would complete the program in 2008 after all units are delivered, though with a possibility of more orders being placed in the future as need be.
Based on the F/A-22, the swing-wing NATF was proposed for the U.S. Navy to replace the F-14 Tomcat, though the program was subsequently cancelled in 1993. Another more recent proposal is the FB-22, which would be used as a deep strike bomber for the USAF. There has yet to be any word on whether the USAF plans further development of the program.
The Raptor's combat computer systems and power are unmatched by any other fighter planned to be developed by 2020. The AN/APG-77 AESA radar, designed for air-superiority and strike operations, features a low-observable, active-aperture, electronically-scanned array that can track multiple targets in all kinds of weather. The AN/APG-77 changes frequencies more than 1,000 times a second to reduce the chance of being intercepted. Its information is processed by the two Hughes-built Common Integrated Processors. Each CIP operates at 10.5 billion instructions per second and has 300 megabytes of memory. Unprecedented amounts of information can be gathered from the radar and other onboard and offboard systems, filtered by the CIP, and offered in easy-to-digest ways on several cockpit displays, enabling the pilot to remain on top of complicated situations.
The Raptor is designed to carry its air-to-air missiles in internal bays to avoid disrupting its stealthiness. The missiles are launched by hydraulic arms that hurl them away from the jet so quickly that the weapons-bay doors pop open for less than one second. The plane can also carry bombs such as the large JDAM and the new Small Diameter Bomb . It can carry non-stealthy weapons on four external hardpoints, but this vastly increases the plane's radar signature.
- F/A-22 Raptor Congressional Research Service report, 5 January 2005
- History of the F-22 program
- Stealth fighter crashes, a December 2004 article from the Las Vegas Review-Journal
Specifications (F/A-22 Raptor)
- Crew: 1
- Length: 62 ft 1 in (18.90 m)
- Wingspan: 44 ft 6 in (13.56 m)
- Height: 16 ft 5 in (5.08 m)
- Wing area: 840 ft² 78.04 m²
- Empty: 31,670 lb (14,365 kg)
- Loaded: 60,000 lb (27,216 kg)
- Maximum takeoff: 80,000 lb (36,500 kg)
- Powerplant: 2x Pratt & Whitney F119-PW-100 turbofans, 35,000 lbf (156 kN) thrust each
- Maximum speed: mph (2120 km/h) Mach 1.58
- Range: miles ( km)
- Service ceiling: 50,000 ft (15,240 m)
- Rate of climb: ft/min ( m/min)
- Wing loading: lb/ft² ( kg/m²)
- Guns: 1x M61 Vulcan 20 mm Gatling gun with 480 rounds
- Missiles: 6x AIM-120 AMRAAM, 2x AIM-9 Sidewinder
- Bombs: 2x JDAM
- 4x external hardpoints can be fitted to carry weapons or fuel tanks, each with a capacity of 5,000 lb (2,270 kg)
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