F-22 Raptor-Ground Breaker or Technological Nightmare
By Willie Bodenstein
The Lockheed Martin and project partner Boeing F-22 Raptor is the result of the USAF's (United States Air Force) Advanced Tactical Fighter (ATF) program.
In July 1986 with the growing threat of the of Soviet Su-27 "Flanker" and MiG-29 "Fulcrum" the U.S. Air Force issued a request for proposals for an Advanced Tactical Fighter air superiority fighter to replace the F-15 Eagle and F-16 Fighting Falcon. Two proposals were received, one for a team consisting of Northrop and McDonnell Douglas and one from a consortium consisting of Lockheed, Boeing and General Dynamics. Both companies were granted 50 months in which to developed two flying prototypes, YF-22 for Lockheed and YF-23 for Northrop, for demonstration and evaluations purposes.
Designed primarily as an air superiority fighter the F-22 has additional capabilities including ground attack, electronic warfare and signals intelligence roles and it is the first operational aircraft to combine super-cruise, super-manoeuvrability, stealth, and sensor fusion in a single weapons platform. Test and demonstration flights were held during April 1991 and on the 23 April Lockheed's YF-22 was announced the winner. Although Northrop's YF-23 was the more stealthier and faster the YF-22's superior manoeuvrability clinched the deal.
Lockheed Martin Aeronautics was to be responsible for the manufacturing the airframe whilst Boeing supplied additional airframe components and was responsible for avionics integration and training. Component production was spread over almost 1,000 sub-contractors which, although leading to the creation of numerous jobs, contributed to cost over runs and delays. Final assembly took place at Lockheed's Georgia facility.
Production of the F-22 powered by dual Pratt & Whitney F119-PW-100 afterburning turbofan engines differed from the prototype by having the canopy moved rearwards by seven inches (18 cm) and the engine intakes moved back by 14 inches (36 cm). The wing swept-back angle was decreased from 48º to 42º and the trailing edges were reworked, the vertical stabilizers were reduced in area by 20% and shifted rearwards. The F-22 gained weight during development leading to some reduction in range and aerodynamic performance although the re-working of the wings led to improvement in the stealth capabilities.
On 7 September 1997, almost 11 years after the request for proposal, Lockheed Martin test pilot Steven M. Rainey took the sky for the F-22's first flight. It was to be another eight years on 15 December 2005 before the first of 187 F-22 Raptor Stealth Fighters left the factory floor for service in the United Sates Air Force (USAAF).
Minor mechanical problems and navigational software failures as well as pilots experiencing hypoxia-like symptoms, breathing difficulties, respiratory problems decreased level of alertness as well as or memory loss led to the imposition of distance and altitude flight restrictions. Some $24 million were spend to investigate the problems. The investigation found that carbon filters were defective, the on-board oxygen generating system unexpectedly reduced oxygen levels during high-G manoeuvres and the breathing regulator/anti-g valve was found to be defective, inflating and deflating the vest at high G manoeuvres restricting the pilot's breathing during the critical phase of flight. In 2012 the carbon filters were changed and, in addition to the primary and manual backup, a supplemental automatic oxygen backup system was installed. However, the breathing problems still persist.
The F-22 was plagued by problems and accidents. The 2nd prototype had crashed due to a flight control software error. Fortunately the test pilot, Tom Morgenfeld escaped without injury. The first delivery ready F-22 crashed on 20 December 2004 during take-off because of a flight-control system malfunction. The pilot ejected safely. F-22 operations were again grounded. On 25 March 2009 Lockheed test pilot David P. Cooley, during a test flight, momentarily lost consciousness during a high-G manoeuvre. Upon recovery he ejected but died from injuries due to windblast attributed to the aircraft's speed. The investigation found no design issues.
On 16 November 2010 an F-22 crashed because of a bleed air system malfunction after an engine overheat condition shutting down the Environmental Control System. As a result of the accident the fleet was grounded for four months during 2011 and then restricted to flying below 25,000 feet. Operations resumed after a review. The Accident Review Board initially found that he pilot, Captain Jeffrey Haney, was to blame. The DoD's (Department of Defence) Inspector General however found that the facts did not sufficiently support conclusions and that the USAF had erred in blaming Haney. The USAF however stood by its ruling. On 15 November 2012 an F-22 on a training mission crashed due to a chafed electrical wire that had ignited the fluid in a hydraulic line, causing a fire that damaged the flight controls. The pilot fortunately was able to eject safely.
In December 2005 the USAF announced that the F-22 had achieved Initial Operational Capability and in June 2006 Raptors took part in Exercise Northern Edge in Alaska. During simulated combat exercises Raptors downed 108 adversaries with no losses. It was not until December 2007 that the F-22 Raptor that was designed for a lifespan of 30 years and 8,000 flight hours achieved Full Operational Capability.
Software failure problems almost led to tragedy when in February 2007 the first batch of six Raptors was deployed to Kadena Air Base in Korea. Flying from Hickam AFB, Hawaii the flight experienced multiple software system failures while crossing the International Date Line. Fortunately all aircraft returned safely to Hawaii and the problems were solved and the flight departed 24 hours later.
Each F-22 requires a month-long packaged maintenance plan for every 300 flight hours. Although the radar absorbing stealth system of the F-22 is more robust and less sensitive to weather and wear and tear than those used in earlier stealth aircraft almost one third of maintenance time is spend on maintaining the integrity of the radar absorbing skin. In 2014 F-22 fleet availability stood at 63%. The fleet required 43 maintenance man-hours per flight hour at a cost of more than $70,000 per flight hour.
The USAF's original requirement was for 750 Raptors with production starting in 1994. This number was reduced to 648 in 1996, 339 in 1997, 277 in 2003 and subsequently to 183 to be distributed to seven combat squadrons. In 2008, Congress passed a defence spending bill funding of $140 million for an additional four Raptors. In July 2009 F-22 production was stopped making way for the multi role F-35. In December 2011 the 195th (8 test and 187 operational Raptors) was completed and delivered to the USAF on 2 May 2012.
The Raptor capable of a maximum speed of Mach 1.82 during super-cruise and greater than Mach 2 with afterburners is one of a few aircraft that can sustain supersonic flight without engaging fuel guzzling afterburners. The Raptor's powerful thrust vectoring power plants enable it to perform very high alpha manoeuvres whilst the absence of external stores that create considerable drag permits the Raptor to outperform and out manoeuvre most other fighters currently in operational use. The Raptor's stealth features increase its survivability against ground defences and coupled with its advanced active and passive sensors, ability to spot targets at considerable ranges, radar warning receiver, infrared and ultraviolet missile launch detector, active electronically scanned array radar, as well as increase weapons range make the F-22 a force to be reckoned with.
Carrying armaments internally maintains the aircraft's stealth and minimizes additional drag. Typically six launchers for beyond-visual-range missiles will be accommodated in the main bay. The main bay may also be used to house air-to-surface weapons. Side bays house a launcher for short range missiles. A M61A2 Vulcan 20 mm cannon is housed internally in the right wing root its muzzle covered by a retractable door to maintain stealth. While the F-22 typically carries weapons internally the wings include four hardpoints. Each hard point, rated to handle 5,000 lb (2,300 kg), can carry a launcher holding two air-to-air missiles or a detachable 600 gallon external fuel tank.
Despite all the initial problems Raptors showed their potential during Red Flag exercises held during February 2007. The Raptor led Blue Force 22s maintained air dominance against a superior Red Force equipped with F-15 and F-16s. The Blue force achieved 241 kills for two losses one of which was a Raptor. No sorties were missed because of maintenance or other failures.
Operationally approved the F-22 was ready for deployment and in November 2007 Raptors of the 90th Fighter Squadron performed their first NORAD interception when they followed two Russian Tu-95MS "Bear-H" bombers that was approaching US airspace close to Alaska. No Raptors were deployed during the 2007 Middle East Crisis. It was to be almost seven years when in 2014 the F-22 performed the type's first combat sorties during the American-led intervention in Syria. Between September 2014 and July 2015, F-22s flew 204 sorties over Syria, dropping 270 bombs at some 60 locations.
Although it seems as if the most of the Raptors initial problems has been sorted and that in exercises against less technological advanced types it has a definite edge it remains to be proven in combat with similarly advanced Russian and Chinese types. Only time will tell if Raptor is indeed as good as is claimed.