Lockheed Martin F-22 Raptor

F-22 Raptor
An F-22 flies over Andrews Air Force Base in 2008.
Role	Stealth air superiority fighter
National origin	United States
Manufacturer	Lockheed Martin Aeronautics Boeing Defense, Space & Security
First flight	7 September 1997
Introduction	15 December 2005
Status	In service
Primary user	United States Air Force
Produced	1996–2011
Number built	195 (8 test and 187 operational aircraft)[1]
Program cost	US$67.3 billion (as of 2010)[2]
Unit cost	US$150 million (flyaway cost for FY2009)[3]
Developed from	Lockheed YF-22
Developed into	Lockheed Martin X-44 MANTA Lockheed Martin FB-22

The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities.^[4] The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.

The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.^[5][6]

Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35.^{[N 1]} The last F-22 was delivered in 2012.

Development[edit]

Origins[edit]

In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air superiority fighter program was influenced by the emerging worldwide threats, including development and proliferation of Soviet Su-27 "Flanker"- and MiG-29 "Fulcrum"-class fighter aircraft.^[8] It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.^[9][10]

Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of various analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed-led team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories.^[11] During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractors teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, which added substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.^[12]

Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed-lead team as the winner of the ATF competition.^[13] The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable.^[14] The aviation press speculated that the Lockheed-led team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF),^{[N 2]} but by 1992, the Navy had abandoned NATF.^[15]

Production and procurement[edit]

As the program moved into full-scale development, or Engineering & Manufacturing Development (EMD), the production F-22 would have notable differences from the YF-22 despite having broadly similar shapes. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%.^[16] To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics.^[17][18] Increasing weight during development caused slight reductions in range and maneuver performance.^[19]

Prime contractor Lockheed Martin Aeronautics^{[N 3]} manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems.^[20] F-22 production supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, which increased Congressional support.^[21][22] Production spanned 15 years at a peak rate of roughly two airplanes per month.^[23][24] The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997.^[25][26] In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award.^[27] Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.^[28]

The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003.^[29] In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381.^[30][31] A multi-year procurement plan was implemented in 2006 to save $15 billion, and program's total cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons.^[32] In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.^[33][34]

The first two F-22s built were EMD aircraft in the Block 1.0^{[N 4]} configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.^[35][36]

The numerous new technologies in the F-22 resulted in substantial cost overruns and delays.^[37] Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost.^[38] As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.^[39][2]

Ban on exports[edit]

The F-22 cannot be exported under American federal law to protect its stealth technology and other high-tech features.^[40][41] Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export.^[42] In September 2006, Congress upheld the ban on foreign F-22 sales.^[43] Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.^[44][45]

Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s,^[46][47] citing the F-22's known capabilities and F-35's delays and developmental uncertainties.^[48] However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles.^[49] The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP.^[50][51] With the end of F-22 production, Japan chose the F-35 in December 2011.^[52] Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.^[53][54]

Production termination[edit]

Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22,^[55] and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner.^[56][57] The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.^[58]

In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan,^[59] and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft.^[60] In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.^[61] Issues with the F-22's reliability and availability also raised concerns.^[42][62] After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap.^[63][64] Gates stated that the decision was taken in light of the F-35's capabilities,^[65] and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.^[66]

In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).^[67] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost.^[68] Lockheed Martin stated that restarting the production line itself would cost about $200 million.^[69] Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle.^[70] Later attempts to retrieve this tooling found that the containers were empty.^[71]

Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern.^[58] In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays.^[72] In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.^[73][74]

In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. in air superiority capabilities.^[75] Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment.^[76] On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.^[77]

Upgrades[edit]

The first aircraft with combat-capable Block 3.0 software flew in 2001.^[78] Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Airframes from production Lot 5 onward are fitted with the improved AN/APG-77(V)1, which incorporates air-to-ground modes; certification of the new radar was completed in March 2007.^[79] Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011.^[80][81] To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.^[82]

Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.^[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.^[85]

In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include next-generation sensors, new hardware and antennas, cockpit improvements, and a more advanced helmet mounted display and cuing system. Other enhancements being developed include infra-red search and track functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.^[85][86][87]

The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program".^[88] Investigations are being made for upgrades to extend their useful lives further.^[89] In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.^[90]

Design[edit]

Overview[edit]

The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.^[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform.^[92] The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.^[93]

The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.^{[94][N 5]}

The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles.^[96][97] The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m).^[98] The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.^[99]

The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra.^[100] The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.^[101][102]

Avionics[edit]

Key avionics include Sanders/General Electric AN/ALR-94 electronic warfare system, Lockheed Martin AN/AAR-56 infrared and ultraviolet Missile Launch Detector (MLD) and Westinghouse/Texas Instruments AN/APG-77 active electronically scanned array (AESA) radar. The MLD uses six sensors to provide full spherical infrared coverage.^[103] Among the most technically complex equipment on the aircraft is the ALR-94 system, a passive radar detector with more than 30 antennas blended into the wings and fuselage for all-round radar warning receiver (RWR) coverage. Its range (250+ nmi) exceeds the radar's and can cue radar emissions to be confined to a narrow beam (down to 2° by 2° in azimuth and elevation) to increase stealth. Depending on the detected threat, the defensive systems can prompt the pilot to release countermeasures such as flares or chaff. The ALR-94 can be used as a passive detection system capable of searching targets and providing enough information for a radar lock on. Tactical communication between F-22s is performed using the directional Inter/Intra-Flight Data Link (IFDL).^[104][105]

The APG-77 radar has a low-observable, active-aperture, electronically scanned array that can track multiple targets under any weather conditions. Radar emissions can also be focused to overload enemy sensors as an electronic-attack capability. The radar changes frequencies more than 1,000 times per second to lower interception probability and has an estimated range of 125–150 mi (201–241 km) against a 11 sq ft (1 m²) target and 250 mi (400 km) or more in narrow beams. F-22s from Lot 5 and on are equipped with the APG-77(V)1, which provides full air-to-ground functionality (high-resolution synthetic aperture radar mapping, ground moving target indication and track (GMTI/GMTT), and other strike modes).^[79][106] Radar and Communication/Navigation/Identification (CNI) information are processed by two Hughes Common Integrated Processor (CIP)s, each capable of processing up to 10.5 billion instructions per second. In a process known as sensor fusion, data from the radar, other sensors, and external systems is filtered and combined by the CIP into a common view, reducing pilot workload.^[107]

The F-22's ability to operate close to the battlefield gives the aircraft threat detection and identification capability comparative with the RC-135 Rivet Joint, and the ability to function as a "mini-AWACS", though its radar is less powerful than those of dedicated platforms. This allows the F-22 to rapidly designate targets for allies and coordinate friendly aircraft.^[106] The IEEE 1394B bus developed for the F-22 was derived from the commercial IEEE 1394 "FireWire" bus system.^[108] In 2007, the F-22's radar was tested as a wireless data transceiver, transmitting data at 548 megabits per second and receiving at gigabit speed, far faster than the Link 16 system.^[109]

The F-22's software has some 1.7 million lines of code, the majority involving processing radar data.^[110] Former Secretary of the USAF Michael Wynne blamed the use of the DoD's Ada for cost overruns and delays on many military projects, including the F-22. The integrated nature of the avionics have also made upgrades challenging; consequently, open-system architecture for the aircraft is currently planned in order to facilitate future upgrades.^[85][111]

Cockpit[edit]

The F-22 has a glass cockpit with all-digital flight instruments. The monochrome head-up display offers a wide field of view and serves as a primary flight instrument; information is also displayed upon six color liquid-crystal display (LCD) panels.^[112] The primary flight controls are a force-sensitive side-stick controller and a pair of throttles. The USAF initially wanted to implement direct voice input (DVI) controls, but this was judged to be too technically risky and was abandoned.^[113] The canopy's dimensions are approximately 140 inches long, 45 inches wide, and 27 inches tall (355 cm × 115 cm × 69 cm) and weighs 360 pounds.^[114] The canopy was redesigned after the original design lasted an average of 331 hours instead of the required 800 hours.^[62]

The F-22 has integrated radio functionality, the signal processing systems are virtualized rather than as a separate hardware module.^[115] There have been several reports on the F-22's inability to communicate with other aircraft, with voice communication possible but not data transfer.^[116]

The integrated control panel (ICP) is a keypad system for entering communications, navigation, and autopilot data. Two 3 in × 4 in (7.6 cm × 10.2 cm) up-front displays located around the ICP are used to display integrated caution advisory/warning data, Communications/Navigation/Identification (CNI) data and also serve as the stand-by flight instrumentation group and fuel quantity indicator.^[117][118] The stand-by flight group displays an artificial horizon, for basic instrument meteorological conditions. The 8 in × 8 in (20 cm × 20 cm) primary multi-function display (PMFD) is located under the ICP, and is used for navigation and situation assessment. Three 6.25 in × 6.25 in (15.9 cm × 15.9 cm) secondary multi-function displays are located around the PMFD for tactical information and stores management.^[118]

The ejection seat is a version of the ACES II (Advanced Concept Ejection Seat) commonly used in USAF aircraft, with a center-mounted ejection control.^[119] The F-22 has a complex life support system, which includes the on-board oxygen generation system (OBOGS), protective pilot garments, and a breathing regulator/anti-g (BRAG) valve controlling flow and pressure to the pilot's mask and garments. The pilot garments were developed under the Advanced Technology Anti-G Suit (ATAGS) project and are to protect against chemical/biological hazards and cold-water immersion, counter g-forces and low pressure at high altitudes, and provide thermal relief.^[120] Following a series of hypoxia-related issues, the life support system was revised to include a backup oxygen system and a new flight vest valve.^[82]

Armament[edit]

The F-22 has three internal weapons bays: a large main bay on the bottom of the fuselage, and two smaller bays on the sides of the fuselage, aft of the engine intakes.^[121] The main bay is split along the centerline and can accommodate six LAU-142/A launchers for beyond-visual-range missiles and each side bay has an LAU-141/A launcher for short-range missiles.^[122] Four of the launchers in the main bay can be replaced with two bomb racks that can each carry one 1,000 lb (450 kg) or four 250 lb (110 kg) bombs.^[92] Carrying armaments internally maintains the aircraft's stealth and minimizes additional drag. Missile launches require the bay doors to be open for less than a second, during which hydraulic arms push missiles clear of the aircraft; this is to reduce vulnerability to detection and to deploy missiles during high speed flight.^[123]

The F-22 can carry air-to-surface weapons such as bombs with JDAM guidance and the Small Diameter Bomb, but cannot self-designate for laser-guided weapons.^[124] Internal air-to-surface ordnance is limited to 2,000 lb (910 kg).^[125] An internally mounted M61A2 Vulcan 20 mm rotary cannon is embedded in the aircraft's right wing root with the muzzle covered by a retractable door to maintain stealth.^[126] The radar projection of the cannon fire's path is displayed on the pilot's head-up display.^[127]

The F-22's high cruise speed and altitude increase the effective ranges of its munitions, with the aircraft having 50% greater employment range for the AIM-120 AMRAAM and twice the effective range for JDAMs than prior platforms.^[102][128] In testing, an F-22 dropped a GBU-32 JDAM from 50,000 feet (15,000 m) while cruising at Mach 1.5, striking a moving target 24 miles (39 km) away.^[129]

While the F-22 typically carries weapons internally, the wings include four hardpoints, each rated to handle 5,000 lb (2,300 kg). Each hardpoint can accommodate a pylon that can carry a detachable 600-gallon (2,270 L) external fuel tank or a launcher holding two air-to-air missiles; the two inboard hardpoints are "plumbed" for external fuel tanks. The use of external stores degrades the aircraft's stealth and kinematic performance; after releasing stores the external attachments can be jettisoned to restore those characteristics.^[130] A stealthy ordnance pod and pylon was being developed to carry additional weapons in the mid-2000s.^[131]

Stealth[edit]

The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye.^[132] The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles.^[133] Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.^[134]

Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair.^[106] While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble".^[135] Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.^{[N 6]}

The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision.^[137] Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging.^[138][139] According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.^[140]

Operational history[edit]

Designation and testing[edit]

The YF-22 was originally given the unofficial name "Lightning II", after the World War II Lockheed P-38 Lightning fighter, which persisted until the mid-1990s, when the USAF officially named the aircraft "Raptor"; "Lightning II" was later given to the F-35. The aircraft was also briefly dubbed "SuperStar" and "Rapier".^[141] In September 2002, USAF changed the Raptor's designation to F/A-22, mimicking the Navy's McDonnell Douglas F/A-18 Hornet and intended to highlight a planned ground-attack capability amid debate over the aircraft's role and relevance. The F-22 designation was reinstated in December 2005, when the aircraft entered service.^[92][142]

Flight testing of the F-22 began in 1997 with Raptor 4001, the first EMD jet, and eight more EMD F-22s would participate in the flight test program at Edwards AFB. The first two aircraft tested flying qualities, air vehicle performance, propulsion, and stores separation. The third aircraft, the first to have production-level internal structure, tested flight loads, flutter, and JDAM separation, while two non-flying F-22s were built for static loads testing and fatigue testing. Subsequent EMD aircraft tested avionics, CNI, and observables.^[35] Raptor 4001 was retired from flight testing in 2000 and subsequently sent to Wright-Patterson Air Force Base for survivability testing, including live fire testing and battle damage repair training.^[143] Other EMD F-22s have been used for testing upgrades and as maintenance trainers.^[144] The first production F-22 was delivered to Nellis AFB, Nevada, in January 2003 for Initial Operational Test & Evaluation (IOT&E).^[145]

In May 2006, a released report documented a problem with the F-22's forward titanium boom, caused by defective heat-treating. This made the boom on roughly the first 80 F-22s less ductile than specified and potentially shortened the part's life. Modifications and inspections were implemented to the booms to restore life expectancy.^[89][146]

In August 2008, an unmodified F-22 of the 411th Flight Test Squadron performed the first ever air-to-air refueling of an aircraft using synthetic jet fuel as part of a wider USAF effort to qualify aircraft to use the fuel, a 50/50 mix of JP-8 and a Fischer–Tropsch process-produced, natural gas-based fuel.^[147] In 2011, an F-22 flew supersonic on a 50% mixture of biofuel derived from camelina.^[148]

Introduction into service[edit]

In December 2005, the USAF announced that the F-22 had achieved Initial Operational Capability (IOC).^[149] During Exercise Northern Edge in Alaska in June 2006, in simulated combat exercises 12 F-22s of the 94th FS downed 108 adversaries with no losses.^[32] In the exercises, the Raptor-led Blue Force amassed 241 kills against two losses in air-to-air combat, with neither "loss" being an F-22. During Exercise Red Flag 07-1 in February 2007, 14 F-22s of the 94th FS supported Blue Force strikes and undertook close air support sorties. Against superior numbers of Red Force Aggressor F-15s and F-16s, 6–8 F-22s maintained air dominance throughout and provided airborne electronic surveillance. No sorties were missed because of maintenance or other failures; a single F-22 was judged "lost" against the defeated opposing force.^[150]

The F-22 achieved Full Operational Capability (FOC) in December 2007, when General John Corley of Air Combat Command (ACC) officially declared the F-22s of the integrated active duty 1st Fighter Wing and Virginia Air National Guard 192d Fighter Wing fully operational.^[151] This was followed by an Operational Readiness Inspection (ORI) of the integrated wing in April 2008, in which it was rated "excellent" in all categories, with a simulated kill-ratio of 221–0.^[152]

Maintenance and training[edit]

Each aircraft requires a three-week packaged maintenance plan (PMP) every 300 flight hours.^[153] The stealth coatings of the F-22 were designed to be more robust and weather-resistant than those used in earlier stealth aircraft.^[106] However, early coatings still experienced issues with rain and moisture when F-22s were initially posted to Guam in 2009.^[154] The stealth system account for almost one third of maintenance, with coatings being particularly demanding. More durable stealth coatings derived from those on the F-35 are being considered for future upgrades in order to reduce maintenance efforts.^[155][85] F-22 depot maintenance is performed at Ogden Air Logistics Complex at Hill AFB, Utah.^[156]

F-22s were available for missions 63% of the time on average in 2015, up from 40% when the aircraft was introduced in 2005. Maintenance hours per flight hour was also improved from 30 early on to 10.5 by 2009, lower than the requirement of 12; man-hours per flight hour was 43 in 2014. When introduced, the F-22 had a Mean Time Between Maintenance (MTBM) of 1.7 hours, short of the required 3.0; this rose to 3.2 hours in 2012.^[62][88] By fiscal year 2015, the cost per flight hour was $59,116.^[157]

To reduce operating costs and lengthen the F-22's service life, some pilot training sorties are performed using flight simulators, while the T-38 Talon is used for adversary training. Attrition reserve aircraft numbers are limited due to the small fleet size.^[153]

Deployments[edit]

F-22 fighter units have been frequently deployed to Kadena Air Base in Okinawa, Japan.^[158] In February 2007, on the aircraft's first overseas deployment to Kadena Air Base, six F-22s of 27th Fighter Squadron flying from Hickam AFB, Hawaii, experienced multiple software-related system failures while crossing the International Date Line (180th meridian of longitude). The aircraft returned to Hawaii by following tanker aircraft. Within 48 hours, the error was resolved and the journey resumed.^[159][160] F-22s have also been involved in training exercises in South Korea and Malaysia.^[161][162]

In November 2007, F-22s of 90th Fighter Squadron at Elmendorf AFB, Alaska, performed their first NORAD interception of two Russian Tupolev Tu-95MS bombers.^[163] Since then, F-22s have also escorted probing Tupolev Tu-160 bombers.^[164]

Defense Secretary Gates initially refused to deploy F-22s to the Middle East in 2007;^[165] the type made its first deployment in the region at Al Dhafra Air Base in the UAE in 2009. In April 2012, F-22s have been rotating into Al Dhafra, less than 200 miles from Iran;^[166][167] the Iranian defense minister referred to the deployment as a security threat.^[168] In March 2013, the USAF announced that an F-22 had intercepted an Iranian F-4 Phantom II that approached within 16 miles of an MQ-1 Predator flying off the Iranian coastline.^[140]

On 22 September 2014, F-22s performed the type's first combat sorties by conducting some of the opening strikes of Operation Inherent Resolve, the American-led intervention in Syria; aircraft dropped 1,000-pound GPS-guided bombs on Islamic State targets near Tishrin Dam.^[169][170] Between September 2014 and July 2015, F-22s flew 204 sorties over Syria, dropping 270 bombs at some 60 locations.^[171] Throughout their deployment, F-22s conducted close air support (CAS) and also deterred Syrian, Iranian, and Russian aircraft from attacking U.S.-backed Kurdish forces and disrupting U.S. operations in the region.^{[172][173][174]} F-22s also participated in the U.S. strikes on pro-government forces in eastern Syria on 7 February 2018.^{[175][176][177]} These strikes notwithstanding, the F-22's main role in the operation was gathering intelligence, surveillance and reconnaissance.^[178]

In late 2014, the USAF was testing a rapid deployment concept involving four F-22s and one C-17 for support, first proposed in 2008 by two F-22 pilots. The goal was for the type to be able to set up and engage in combat within 24 hours.^[179][180] Four F-22s were deployed to Spangdahlem Air Base in Germany in August and Lask Air Base in Poland and Amari Air Base in Estonia in September 2015 to train with NATO allies.^[181]

In November 2017, F-22s operating alongside B-52s bombed opium production and storage facilities in Taliban-controlled regions of Afghanistan.^[182] In 2019, the F-22 cost US$35,000 per flight hour to operate.^[183]

Operational problems[edit]

Operational problems have been experienced and some have caused fleet-wide groundings. Critically, F-22 pilots have experienced a decreased mental status, with symptoms that include loss of consciousness, memory loss, emotional lability and neurological changes. Pilots have also experienced lingering respiratory problems and a chronic cough.^[184] A number of possible causes were investigated, including possible exposure to noxious chemical agents from the respiratory tubing, pressure suit malfunction, side effects from oxygen delivery at greater-than-atmospheric concentrations, and oxygen supply disruptions. The fleet was grounded for four months in 2011 before resuming flight, but reports of oxygen issues persisted.^[185] The problems resulted in inflight brain monitoring being considered by the USAF.^[186]

In 2005, the Raptor Aeromedical Working Group, a USAF expert panel, recommended several changes to deal with the oxygen supply issues, though they were initially not funded on cost grounds; the recommended changes received further consideration in 2012.^[187][188] In August 2012, the Pentagon found that the breathing regulator/anti-g (BRAG) valve, used to inflate the pilot's vest during high G maneuvers, was defective, inflating the vest at unintended intervals and restricting the pilot's breathing.^[189] The on-board oxygen generating system (OBOGS) also unexpectedly reduced oxygen levels during high-G maneuvers.^[190] Consequently, new backup oxygen generators were installed and the carbon filters were changed to reduce lung exposure to carbon particulates.^[191] The coughing symptoms have been attributed to acceleration atelectasis ("collapse or closure of a lung resulting in reduced or absent gas exchange") due to high g exposure and the F-22 delivering higher concentrations of oxygen compared to prior aircraft. The presence of toxins and particles in some ground crew was deemed to be unrelated.^[192] After the F-22 Combined Test Force and 412th Aerospace Medicine Squadron determined that breathing restrictions on the pilot were the root cause, the resulting modifications to the life-support equipment and oxygen system allowed the distance and altitude flight restrictions to be lifted on 4 April 2013.^[82][193]

Variants[edit]

• YF-22A – pre-production technology demonstrator for ATF demonstration/validation phase; two were built.
• F-22A – single-seat production version, was designated F/A-22A in early 2000s.
• F-22B – planned two-seat variant, canceled in 1996 to save development costs.^[194]
• Naval F-22 variant – a planned carrier-borne variant of the F-22 with variable-sweep wings for the U.S. Navy's Navy Advanced Tactical Fighter (NATF) program to replace the F-14 Tomcat. Program was canceled in 1993.^[194]

Derivatives[edit]

The FB-22 was a proposed medium-range supersonic stealth bomber for the USAF.^[195] The design was projected to carry up to 30 Small Diameter Bombs to about twice the range of the F-22A.^[196] However, the FB-22 proposal appears to have been canceled with the 2006 Quadrennial Defense Review and subsequent developments, in lieu of a larger subsonic bomber with a much greater range.^[197][198]

The X-44 MANTA, or multi-axis, no-tail aircraft, was a planned experimental aircraft based on the F-22 with enhanced thrust vectoring controls and no aerodynamic surface backup.^[199] The aircraft was to be solely controlled by thrust vectoring, without featuring any rudders, ailerons, or elevators. Funding for this program was halted in 2000.^[200]

In August 2018, Lockheed Martin proposed an F-22 derivative to the USAF and JASDF that would combine an improved F-22 airframe with the avionics and improved stealth coatings of the F-35.^[201] The proposal was not considered by the USAF, while JASDF doubted its merits due to cost and existing export restrictions.^[202][203]

Operators[edit]

 United States

• United States Air Force

The U.S. Air Force is the only operator of the F-22. In July 2018, it had 186 production aircraft in inventory.^[204]

Air Combat Command

• 1st Fighter Wing – Langley Air Force Base, Virginia

27th Fighter Squadron – The first combat F-22 squadron. Began conversion in December 2005.^[205]

94th Fighter Squadron

• 49th Fighter Wing – Holloman Air Force Base, New Mexico^[206]

7th Fighter Squadron (Inactivated in 2014)

8th Fighter Squadron (Reactivated and reassigned to 54th Fighter Group as F-16 training squadron in 2017)

• 53d Wing – Tyndall Air Force Base, Florida

422d Test and Evaluation Squadron (Nellis Air Force Base, Nevada)^[149]

• 57th Wing – Nellis Air Force Base, Nevada

433d Weapons Squadron^[207]

• 325th Fighter Wing – Tyndall Air Force Base, Florida

43d Fighter Squadron – First squadron to operate the F-22 and continues to serve as the Formal Training Unit.^[208]

95th Fighter Squadron^[209]

See Tyndall Air Force Base#Hurricane_Michael

Air Force Materiel Command

• 412th Test Wing – Edwards Air Force Base, California

411th Flight Test Squadron

Pacific Air Forces

• 3d Wing – Elmendorf Air Force Base, Alaska

90th Fighter Squadron^[210]

525th Fighter Squadron

• 15th Wing – Hickam Air Force Base, Hawaii

19th Fighter Squadron – Active Associate squadron to the 199th Fighter Squadron (Hawaii Air National Guard).^[211]

Air National Guard

• 192d Fighter Wing (Associate) – Langley Air Force Base, Virginia

149th Fighter Squadron

• 154th Wing – Hickam Air Force Base, Hawaii^[212]

199th Fighter Squadron

• 325th Fighter Wing Associate Unit (also known as Florida Air National Guard Headquarters Detachment 1) – Tyndall AFB, Florida

Associate ANG unit to 325th Fighter Wing (Air Combat Command)^[213]

Air Force Reserve Command

• 44th Fighter Group (Associate) – Tyndall AFB, Florida

301st Fighter Squadron

• 477th Fighter Group (Associate) – Elmendorf AFB, Alaska

302d Fighter Squadron

Accidents and losses[edit]

The first F-22 crash occurred during takeoff at Nellis AFB on 20 December 2004, in which the pilot ejected safely before impact.^[214] The investigation revealed that a brief interruption in power during an engine shutdown prior to flight caused a flight-control system malfunction;^[35][215] consequently the aircraft design was corrected to avoid the problem. Following a brief grounding, F-22 operations resumed after a review.^[216]

On 25 March 2009, an EMD F-22 crashed 35 miles (56 km) northeast of Edwards AFB during a test flight, resulting in the death of Lockheed Martin test pilot David P. Cooley. An Air Force Materiel Command investigation found that Cooley momentarily lost consciousness during a high-G maneuver, then ejected when he found himself too low to recover. Cooley was killed during ejection by blunt-force trauma from windblast due to the aircraft's speed. The investigation found no design issues.^[217][218]

On 16 November 2010, an F-22 from Elmendorf AFB crashed, killing the pilot, Captain Jeffrey Haney. F-22s were restricted to flying below 25,000 feet, then grounded during the investigation.^[219] The crash was attributed to a bleed air system malfunction after an engine overheat condition was detected, shutting down the Environmental Control System (ECS) and OBOGS. The accident review board ruled Haney was to blame, as he did not react properly and did not engage the emergency oxygen system.^[220] Haney's widow sued Lockheed Martin, claiming equipment defects; she later reached a settlement.^{[221][222][192]} After the ruling, the emergency oxygen system engagement handle was redesigned; the system was eventually replaced by an automatic backup oxygen system (ABOS).^[223] On 11 February 2013, the DoD's Inspector General released a report stating that the USAF had erred in blaming Haney, and that facts did not sufficiently support conclusions; the USAF stated that it stood by the ruling.^[224]

During a training mission, an F-22 crashed to the east of Tyndall AFB, on 15 November 2012. The pilot ejected safely and no injuries were reported on the ground.^[225] The investigation determined that a "chafed" electrical wire ignited the fluid in a hydraulic line, causing a fire that damaged the flight controls.^[226]

Aircraft on display[edit]

EMD F-22A 91-4003 is on display at the National Museum of the United States Air Force.^[227]

Specifications (F-22A)[edit]

Data from USAF,^[92] manufacturers' data,^[228][229] Aviation Week,^[106][230] AirForces Monthly,^[94] and Journal of Electronic Defense,^[105]

General characteristics

• Crew: 1
• Length: 62 ft 1 in (18.92 m)
• Wingspan: 44 ft 6 in (13.56 m)
• Height: 16 ft 8 in (5.08 m)
• Wing area: 840 sq ft (78 m²)
• Airfoil: NACA 64A?05.92 root, NACA 64A?04.29 tip
• Empty weight: 43,340 lb (19,659 kg)
• Gross weight: 64,840 lb (29,411 kg)
• Max takeoff weight: 83,500 lb (37,875 kg)
• Fuel capacity: 18,000 lb (8,200 kg) internally, or 26,000 lb (12,000 kg) with two external fuel tanks
• Powerplant: 2 × Pratt & Whitney F119-PW-100 augmented turbofans
  • Dry thrust: 26,000 lbf (116 kN) each
  • Thrust with afterburner: >35,000 lbf (156 kN) each^{[N 7][231]}

Performance

• Maximum speed: Mach 2.25 (1,500 mph, 2,414 km/h) at altitude
  • Supercruise: Mach 1.82 (1,220 mph, 1,963 km/h) at altitude
• Range: >1,600 nmi (1,841 mi, 2,963 km) with 2 external fuel tanks
• Ferry range: 1,740 nmi (2,000 mi, 3,220 km)
• Combat radius: 460 nmi (529 mi, 851 km)^{[232][N 8]}
• Service ceiling: 65,000 ft (20,000 m)
• g limits: +9.0/−3.0
• Wing loading: 77.2 lb/sq ft (377 kg/m²)
• Thrust/weight: 1.08 (1.25 with loaded weight and 50% internal fuel)

Armament

• Guns: 1× 20 mm (0.787 in) M61A2 Vulcan 6-barrel rotary cannon, 480 rounds
• Air-to-air mission loadout:
  • 6× AIM-120 AMRAAM
  • 2× AIM-9 Sidewinder
• Air-to-ground mission loadout:
  • 2× 1,000 lb (450 kg) JDAM or 8× 250 lb (110 kg) GBU-39 Small Diameter Bombs
  • 2× AIM-120 AMRAAM
  • 2× AIM-9 Sidewinder
• Hardpoints: 4× under-wing pylon stations can be fitted to carry 600 U.S. gallon (2,270 L) drop tanks or weapons, each with a capacity of 5,000 lb (2,270 kg).^[233]

Avionics

• AN/APG-77 or AN/APG-77(V)1 radar: 125–150 miles (201–241 km) against 1 m² (11 sq ft) targets (estimated range), 250 miles (400 km) in narrow beams
• AN/AAR-56 Missile Launch Detector (MLD)
• AN/ALR-94 radar warning receiver (RWR): 250 nautical miles (460 km) or more detection range
• MJU-39/40 flares for protection against IR missiles^[234]

Notable appearances in media[edit]

See also[edit]

Related development

• Lockheed YF-22 – Prototype fighter aircraft for the US Air Force Advanced Tactical Fighter program
• Lockheed Martin FB-22 – Proposed bomber aircraft for the US Air Force derived from the F-22 Raptor
• Lockheed Martin X-44 MANTA – Conceptual aircraft design by Lockheed Martin

Aircraft of comparable role, configuration and era

• Lockheed Martin F-35 Lightning II – Family of fifth-generation stealth combat aircraft
• Chengdu J-20 – Chinese fifth-generation fighter
• Sukhoi Su-57 – Russian fifth-generation fighter aircraft

Related lists

• List of fighter aircraft
• List of Lockheed aircraft
• List of active United States military aircraft
• List of megaprojects, Aerospace

References[edit]

Notes[edit]

Citations[edit]

Bibliography[edit]

External links[edit]

Wikimedia Commons has media related to: Lockheed Martin F-22 Raptor (category)

• Official website
• F-22 page on GlobalSecurity.org
• F-22 Demo at 2007 Capital Airshow in Sacramento – with narrative by F-22 pilot Paul "Max" Moga