Editing Lockheed Martin F-22 Raptor (section)

===Full-scale development===
The program formally moved to full-scale development, or [[Manufacturing readiness level#Definitions|Engineering & Manufacturing Development]] (EMD), in August 1991. The production F-22 design (internally designated Configuration 645) had also evolved to have notable differences from the YF-22, which was immature due to being frozen relatively soon after the complete redesign in the summer of 1987.{{refn|The YF-22 outer lines were frozen to allow construction to begin in 1988, resulting in the shaping being rather unrefined, especially compared to the YF-23.<ref name="f22_evolution_p2"/>|group=N}} While the overall layout was similar, the external geometry saw significant alterations; the wing's [[leading edge]] sweep angle was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%.<ref name="NASA">{{cite web |url=http://oea.larc.nasa.gov/PAIS/Partners/F_22.html |archive-url=https://web.archive.org/web/20040118030146/http://oea.larc.nasa.gov/PAIS/Partners/F_22.html |archive-date=18 January 2004 |title=F-22 Partners |work=NASA |access-date=25 July 2009}}</ref> The radome shape was changed for better radar performance, the wingtips were clipped for antennas, and the dedicated airbrake was eliminated. To improve pilot visibility and aerodynamics, the canopy was moved forward {{convert|7|in|cm}} and the engine inlets moved rearward {{convert|14|in|cm}}. The shapes of the fuselage, wing, and [[stabilator]] trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. The internal structural design was refined and reinforced, with the production airframe designed for a service life of 8,000 hours.<ref name="f22_evolution_p2">{{cite web |last=Hehs |first=Eric |url=https://www.codeonemagazine.com/article.html?item_id=180 |title=F-22 Raptor Design Evolution, Part 2 |publisher=Lockheed Martin |date=16 October 1998 |access-date=13 March 2023 |archive-date=19 December 2022 |archive-url=https://web.archive.org/web/20221219185803/https://www.codeonemagazine.com/article.html?item_id=180 |url-status=live}}</ref><ref>Pace 1999, pp. 12–13.</ref> The revised shaping was validated with over 17,000 additional hours of wind tunnel testing and further RCS testing at [[Helendale, California]] and the USAF [[National Radar Cross-section Facility|RATSCAT range]] before the first flight. Increasing weight during EMD due to demanding ballistic survivability requirements and [[Scope creep|added capabilities]] caused slight reductions in projected range and maneuver performance.<ref>{{cite magazine |url=http://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/ |title=F-22 weight increase agreed |magazine=Flight International |date=3 May 1995 |publisher=Reed Business Information |archive-url=https://web.archive.org/web/20140112043443/http://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/ |archive-date=12 January 2014}}</ref>

[[File:F-22-flying-alongside-the-FTB.jpg|thumb|An EMD F-22 alongside the Flying Test Bed]]
Aside from advances in air vehicle and propulsion technology, the F-22's avionics were unprecedented in complexity and scale for a combat aircraft, with the integration of multiple sensors systems and antennas, including electronic warfare, communication/navigation/identification (CNI), and software of 1.7&nbsp;million [[Source lines of code|lines of code]] written in [[Ada (programming language)|Ada]]. Avionics often became the pacing factor of the whole program. In light of rapidly advancing computing and semiconductor technology, the avionics was to employ the [[United States Department of Defense|Department of Defense]]'s (DoD) ''[[PAVE|PAVE PILLAR]]'' systems architecture and [[Very High Speed Integrated Circuit Program|Very High Speed Integrated Circuit]] (VHSIC) program technology; the computing and processing requirements were equivalent to multiple contemporary [[Cray#Cray Research Inc. and Cray Computer Corporation: 1972–1996|Cray]] supercomputers to achieve [[sensor fusion]].<ref>Aronstein and Hirschberg 1998, p. 170.</ref><ref name="B3.0SW">[http://www.fas.org/man/dod-101/sys/ac/docs/man-ac-f22-010105.htm "F-22 aircraft No. 4005 completes successful first flight"]. {{Webarchive|url=https://web.archive.org/web/20170629121402/https://fas.org/man/dod-101/sys/ac/docs/man-ac-f22-010105.htm |date=29 June 2017}}. [[Federation of American Scientists]]. Retrieved 23 July 2009.</ref> To enable early looks and troubleshooting for mission software development, the software was ground-tested in Boeing's Avionics Integration Laboratory (AIL) and flight-tested on a [[Boeing 757#Government, military, and corporate|Boeing 757]] modified with F-22 avionics and sensors, called Flying Test Bed (FTB).<ref name="f22_flight_test_update"/><ref>{{cite web |last=Norris |first=Guy |url=https://aviationweek.com/boeing-readies-f-22-flying-lab-tests |title=Boeing Readies F-22 Flying Lab for Tests |date=9 June 2008 |work=Aviation Week & Space Technology}}</ref> Because much of the F-22's avionics design occurred in the 1990s as the electronics industry was shifting from military to commercial applications as the predominant market, avionics upgrade efforts was initially difficult and protracted due to changing industry standards; for instance, [[C (programming language)|C]]/[[C++]] rather than [[Ada (programming language)|Ada]] became predominant programming languages.<ref name="raptorroadmap2019"/>

[[File:F-22 Raptor wytwórnie.png|thumb|left|Manufacturers of the F-22]]
The roughly equal division of work amongst the team largely carried through from Dem/Val to EMD, with prime contractor Lockheed responsible for the forward fuselage and control surfaces, General Dynamics for the center fuselage, and Boeing for aft fuselage and wings. Lockheed [[General Dynamics#Divestitures|acquired General Dynamics]]' fighter portfolio at [[Fort Worth, Texas]] in 1993 and thus had the majority of the airframe manufacturing, and merged with [[Martin Marietta]] in 1995 to form [[Lockheed Martin]]. While Lockheed primarily performed Dem/Val work at its Skunk Works sites in Burbank and Palmdale, [[California]], it shifted its program office and EMD work from Burbank to [[Marietta, Georgia]], where it performed final assembly; [[Boeing Defense, Space & Security|Boeing]] manufactured airframe components, performed avionics integration and developed the training systems in [[Seattle, Washington]]. The EMD contract originally ordered seven single-seat F-22As and two twin-seat F-22Bs, although the latter was canceled in 1996 to reduce development costs and the orders were converted to single seaters.<ref>Aronstein and Hirschberg 1998, p. 118.</ref> The first F-22A, an EMD aircraft with [[United States military aircraft serial numbers|tail number]] 91-4001, was unveiled at [[United States Air Force Plant 6|Air Force Plant 6]] in [[Dobbins Air Reserve Base]] in Marietta on 9 April 1997 where it was officially named "Raptor".{{refn|The YF-22 was originally given the unofficial name "Lightning II", from the World War II [[Lockheed P-38 Lightning]] fighter which persisted until the mid-1990s, when the USAF officially named the F-22 "Raptor". The aircraft was also briefly dubbed "SuperStar" and "Rapier".<ref>[http://www.aerospaceweb.org/question/history/q0221.shtml "Military Aircraft Names."] {{Webarchive|url=http://arquivo.pt/wayback/20091012134155/http://www.aerospaceweb.org/question/history/q0221.shtml |date=12 October 2009}} ''Aerospaceweb.org.'' Retrieved: 26 September 2010. {{unreliable source|date=February 2024}}</ref>|group=N}} The aircraft first flew on 7 September 1997, piloted by chief test pilot Alfred "Paul" Metz.{{refn|Metz was previously the chief test pilot for the YF-23.|group=N}}<ref name=F-22_chrono>[http://www.f22-raptor.com/about/chronology.html "Chronology of the F-22 Program"]. {{webarchive|url=https://web.archive.org/web/20080307071916/http://www.f22-raptor.com/about/chronology.html |date=7 March 2008}} ''F-22 Team'', 4 November 2012. Retrieved 23 July 2009.</ref><ref>{{cite web |archive-url=https://web.archive.org/web/20140705075752/http://lockheedmartin.com/us/100years/stories/f-22.html |archive-date=2014-07-05 |title=F-22 Raptor |publisher=Lockheed Martin |url=http://www.lockheedmartin.com/us/100years/stories/f-22.html |url-status=dead |date=1 July 2014}}</ref> The Raptor's designation was briefly changed to F/A-22 starting in September 2002, mimicking the Navy's [[McDonnell Douglas F/A-18 Hornet|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.<ref name="f22_factsheet"/><ref name="afp_20051205">"U.S. to Declare F-22 Fighter Operational". [[Agence France-Presse]], 15 December 2005.</ref>

[[File:Usaf.kc135.750pix.jpg|thumb|An EMD F-22 refuels from a [[KC-135 Stratotanker|KC-135]] during testing; the attachment on the back top is for a spin recovery chute.|alt=Rear/starboard view of aerial refueling tanker transferring fuel to a jet fighter via a long boom. The two aircraft are slightly banking left.]]
The F-22 flight test program consisted of flight sciences, developmental test (DT), and initial operational test and evaluation (IOT&E) by the [[411th Flight Test Squadron]] (FLTS) at Edwards AFB, California, as well as follow-on OT&E and development of tactics and operational employment by the [[422nd Test and Evaluation Squadron]] (TES) at [[Nellis Air Force Base|Nellis AFB]], [[Nevada]]. Nine EMD jets assigned to the 411th FLTS would participate in the test program under the Combined Test Force (CTF) at Edwards. The first two aircraft conducted envelope expansion testing, such as 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 stores separation, while two non-flying F-22s were built for testing static loads and fatigue. Subsequent EMD aircraft and the Boeing 757 FTB tested avionics, environmental qualifications, and observables, with the first combat-capable Block 3.0 software flying in 2001.<ref name="f22_b3.0">{{cite web |url=https://aviationweek.com/f-22-program-completes-program-milestone-first-flight-block-30-software |title=F-22 program completes program milestone in first flight of Block 3.0 software |work=Aviation Week |date=8 January 2001 |access-date=13 March 2023 |archive-date=22 December 2022 |archive-url=https://web.archive.org/web/20221222004312/https://aviationweek.com/f-22-program-completes-program-milestone-first-flight-block-30-software |url-status=live}}</ref> Air vehicle testing resulted in several structural design modifications and retrofits for earlier lots, including tail fin strengthening to resolve buffeting in certain conditions.<ref name=availability_63%/> Raptor 4001 was retired from flight testing in 2000 and subsequently sent to Wright-Patterson AFB for survivability testing, including live fire testing and battle damage repair training.<ref name=f22milestones>{{cite magazine |url=http://www.codeonemagazine.com/gallery_slideshow.html?fa44c7e5ba83d833e4ac50ea5bc58dd6=2&gallery_id=129&gallery_style=3 |title=F-22 Milestones – Part 2 |magazine=Code One Magazine |access-date=16 November 2013 |archive-url=https://web.archive.org/web/20131111122653/http://www.codeonemagazine.com/gallery_slideshow.html?fa44c7e5ba83d833e4ac50ea5bc58dd6=2&gallery_id=129&gallery_style=3 |archive-date=11 November 2013 |url-status=live}}</ref> Other retired EMD F-22s have been used as maintenance trainers.<ref name="3.2A_test">{{cite web |last=Majumdar |first=Dave |url=http://www.flightglobal.com/blogs/the-dewline/2013/05/raptor-4007-starts-testing-inc/ |title=Raptor 4007 starts testing Inc 3.2A upgrade on its 1000th sortie |work=FlightGlobal |date=7 May 2013 |access-date=16 November 2013 |archive-url=https://web.archive.org/web/20131111120715/http://www.flightglobal.com/blogs/the-dewline/2013/05/raptor-4007-starts-testing-inc/ |archive-date=11 November 2013 |url-status=live}}</ref>

[[File:F-22 CRIIS Edwards.png|thumb|left|An EMD F-22 of the 411th FLTS flies over Edwards AFB, California, in 2018.]]
Because the F-22 had been designed to defeat contemporary and projected Soviet fighters, the end of the [[Cold War (1985-1991)|Cold War]] and the [[dissolution of the Soviet Union]] in 1991 had major impacts on program funding; the DoD reduced its urgency for new weapon systems and the following years would see successive reductions in its budget. This resulted in the F-22's EMD being rescheduled and lengthened multiple times. Furthermore, the aircraft's sophistication and numerous technological innovations required extensive testing, which exacerbated the cost overruns and delays, especially from mission avionics. Some capabilities were also deferred to post-service upgrades, reducing the upfront cost but increasing total program cost.<ref>{{cite news |last=Sweetman |first=Bill |url=http://aviationweek.com/awin/rivals-target-jsf |title=Rivals Target JSF |archive-url=https://web.archive.org/web/20160819135759/http://aviationweek.com/awin/rivals-target-jsf |archive-date=19 August 2016 |work=Aviation Week |publisher=McGraw Hill |date=30 November 2010 |access-date=31 August 2011}}</ref><ref>{{cite report |last1=Younossi |first1=Obaid |last2=Stem |first2=David E. |last3=Lorell |first3=Mark A. |last4=Lussier |first4=Frances M. |url=http://www.rand.org/pubs/monographs/MG276.html |title=Lessons Learned from the F/A–22 and F/A–18E/F Development Programs |archive-url=https://web.archive.org/web/20110425192042/http://www.rand.org/pubs/monographs/MG276.html |archive-date=25 April 2011 |publisher=Rand Corporation |year=2005 |access-date=27 August 2011}}</ref> The program transitioned to full-rate production in March 2005 and completed EMD that December, after which the test force had flown 3,496 sorties for over 7,600 flight hours.<ref name=f22milestones/> As the F-22 was designed for upgrades throughout its lifecycle, the 411th FLTS and 422nd TES continued the DT/OT&E and tactics development of these upgrades.<ref name="3.2A_test"/> Derivatives such as the [[Lockheed Martin X-44 MANTA|X-44]] thrust vectoring research aircraft and the [[Lockheed Martin FB-22|FB-22]] medium-range regional bomber were proposed in the late 1990s and early 2000s, although these were eventually abandoned. In 2006, the F-22 development team won the [[Collier Trophy]], American aviation's most prestigious award.<ref>{{cite press release |url=https://naa.aero/userfiles/files/documents/Press%20Releases/Collier%202006%20PR.pdf |title=F-22 Raptor Wins 2006 Collier Trophy |archive-url=https://web.archive.org/web/20160401091019/https://naa.aero/userfiles/files/documents/press%20releases/collier%202006%20pr.pdf |archive-date=1 April 2016 |work=National Aeronautic Association |access-date=23 July 2009}}</ref> Due to the aircraft's sophisticated capabilities, contractors have been targeted by cyberattacks and technology theft.<ref>{{Cite news |last=Minnick |first=Wendell |url=https://www.defensenews.com/breaking-news/2016/03/24/chinese-businessman-pleads-guilty-of-spying-on-f-35-and-f-22/ |title=Chinese Businessman Pleads Guilty of Spying on F-35 and F-22 |work=Defense News |date=24 March 2016 |access-date=9 April 2019 |archive-date=13 March 2023 |archive-url=https://web.archive.org/web/20230313155355/https://www.defensenews.com/breaking-news/2016/03/24/chinese-businessman-pleads-guilty-of-spying-on-f-35-and-f-22/ |url-status=live}}</ref>