Editing Lockheed P-80 Shooting Star (section)

==Design and development==
[[File:Lockheed P-80 Shooting Star cross section profile line drawing.png|thumb|A cross section of the aircraft with labeled parts]]
The XP-80 had a conventional all-metal airframe, with a slim [[low wing]] and [[tricycle landing gear]]. Like most early jets designed during World War II—and before the Allies captured German research data that confirmed the speed advantages of [[swept-wing]]s—the XP-80 had straight wings, similar to previous propeller-driven fighters. It was the first operational jet fighter to have its engine buried in the fuselage, a format previously used in the pioneering German [[Heinkel He 178]] V1 of 1939, and the later British [[Gloster E.28/39]] demonstrator of 1941. Other early jets generally had two engines because of their limited power, these being mounted in external [[nacelle]]s for easier maintenance. With the advent of more powerful British jet engines, a single fuselage-mounted engine was more effective, and this configuration was used by nearly all subsequent fighter aircraft.{{citation needed|date=April 2023}}

Lockheed was the first American aircraft company to start work on a jet-powered aircraft, beginning work on the [[Lockheed L-133|L-133]] in 1939. The L-133 eventually developed into an extremely advanced design, including futuristic features such as [[Canard (aeronautics)|canard]] forewings and a [[blended wing body]], but when Lockheed presented the design to the Army Air Force, it was rejected as being technologically unfeasible.<ref>{{cite book|last=Norton|first=Bill|title=U.S. Experimental & Prototype Aircraft Projects: Fighters 1939-1945|year=2008|publisher=Specialty Press|location=North Branch, Minnesota|isbn=978-1-58007-109-3}}</ref> Instead the USAAF concentrated development around the much less radical [[Bell P-59 Airacomet]], which first flew in October 1942. It quickly became obvious, however, that the P-59's performance was only marginally superior to current piston engined fighters.<ref>{{cite web|title=Lockheed Martin's Skunk Works|author=Jay Miller|url=http://imagery.vnfawing.com/PDF-Archive/Lockheed-Skunk-Works.pdf|archive-url=https://web.archive.org/web/20181001185842/http://imagery.vnfawing.com/PDF-Archive/Lockheed-Skunk-Works.pdf|url-status=dead|archive-date=1 October 2018|page=13}}</ref> Bell performed preliminary work revising the P-59 with a low wing and a single fuselage-mounted engine, to be designated '''XP-59B''', but by this time the Bell factory was swamped with other work so the USAAF transferred the project to Lockheed.<ref>{{cite web|title=A Bell That Didn't Ring|url=https://www.airspacemag.com/military-aviation/a-bell-that-didnt-ring-7948421/}}</ref>

The impetus for development of the P-80 was the discovery by Allied intelligence of the [[Messerschmitt Me 262|Me 262]] in spring 1943, which had made only test flights of its own first quartet (the V1 through V4 airframes) of design prototypes at that time, all fitted with retracting tailwheel landing gear. After receiving documents and blueprints comprising years of British jet aircraft research, the commanding General of the Army Air Force, [[Henry H. Arnold]], believed an [[airframe]] developed to accept the British-made [[de Havilland Goblin|Halford H-1 B "Goblin"]] jet engine could provide the superior performance to match the new German jets, and the Materiel Command's [[Wright Field]] research and development division tasked Lockheed to design the aircraft based on their experience with the L-133. Concept work began on the '''XP-80''' in May 1943. Since the British turbojet was not yet delivered, Lockheed obtained its [[blueprint]] dimensions from Bell as ordered by the USAAF.<ref>{{cite web|title=Lockheed Martin's Skunk Works|author=Jay Miller|url=http://imagery.vnfawing.com/PDF-Archive/Lockheed-Skunk-Works.pdf|page=15}}</ref> Lockheed's team, consisting of 28 [[Aerospace engineering|engineers]], was led by [[Clarence L. "Kelly" Johnson]] in the same manner as the [[P-38 Lightning]], in the same remote building with high security and greater autonomy, a continuation of Lockheed's [[Skunk Works]] style of research and development.{{citation needed|date=April 2023}}

[[File:Lulu-Belle af.jpg|thumb|The original XP-80 prototype ''Lulu-Belle'']]
With the Germans and British clearly far ahead in development, Lockheed was pressed to develop a comparable jet as quickly as possible. Kelly Johnson submitted a design proposal in mid-June and promised that the prototype would be ready for testing in 150 days.{{r|life1945081343}} The Skunk Works team, beginning 26 June 1943, produced the airframe in 143 days,{{r|life1945081343}} delivering it to [[Muroc Army Airfield]] on 16 November.{{citation needed|date=April 2023}}

The project was so secret that only five of the more than 130 people working on it knew that they were developing a jet aircraft, and the British engineer who delivered the Halford H1 engine was detained by the police because Lockheed officials could not vouch for him.<ref name="life1945081343">Felton, James. [https://books.google.com/books?id=1UkEAAAAMBAJ&pg=PA43 "Shooting Star."] ''Life,'' 13 August 1945, pp. 43–46. Retrieved: 25 November 2011.</ref> After the engine had been mated to the airframe, [[foreign object damage]] during the first run-up destroyed the engine. The British engineer who had delivered the engine had warned Lockheed that the skin of the inlet ducts was too thin but the American engineers ignored this warning and both ducts collapsed and were sucked into the engine when at full throttle.<ref name="Gunston 1976, p. 131">Gunston 1976, p. 131.</ref> This delayed the first flight until a second engine (the only other existing)<ref>Gunston 1989, p. 59.</ref> could be delivered from Britain, de Havilland generously donating the engine intended for the prototype [[de Havilland Vampire|Vampire]].<ref>Heppenheimer, T.A. [https://web.archive.org/web/20090326021941/http://www.americanheritage.com/articles/magazine/it/1993/2/1993_2_44.shtml "The Jet Plane is Born."] ''American Heritage magazine,'' Fall 1993. Volume 9, Issue 2. Retrieved: 1 August 2011.</ref><ref name="Gunston 1976, p. 131"/>

The first prototype (44-83020) was nicknamed ''Lulu-Belle'' (also known as "the Green Hornet" because of its paint scheme). Powered by the replacement Halford H1 taken from the prototype de Havilland Vampire jet fighter,<ref group=N>The Vampire's first flight was delayed until 20 September 1943 as a result</ref> it first flew on 8 January 1944, with Lockheed [[test pilot]] [[Milo Burcham]] at the controls. Following this flight, Johnson said, "It was a magnificent demonstration, our plane was a success – such a complete success that it had overcome the temporary advantage the Germans had gained from years of preliminary development on jet planes." The donated British jet engine and program data had no doubt proved invaluable. In test flights, the XP-80 eventually reached a top speed of {{convert|502|mph|km/h kn|abbr=on}} at {{convert |20,480|ft|m| abbr=on}}, making it the first turbojet-powered USAAF aircraft to exceed 500&nbsp;mph in level flight, following the August 1944 record flight of {{convert|504|mph|km/h kn|abbr=on}} by a [[Republic P-47 Thunderbolt variants#XP-47J|special high-speed variant]]<ref>{{cite web|url=http://www.joebaugher.com/usaf_fighters/p47_9.html|title=Republic XP-47J Thunderbolt|author=Joe Baugher|date=5 July 1999|website=USAF Fighters|access-date=10 October 2022}}</ref> of the [[Republic P-47 Thunderbolt]]. Contemporary pilots, when transitioning to pioneering jets like the Shooting Star, were unused to flying at high speed without a loud reciprocating engine and had to learn to rely on the [[airspeed indicator]].{{r|life1945081343}}

[[File:XP-80A Gray Ghost af.jpg|thumb|XP-80A ''Gray Ghost'' in flight]]

The second prototype, designated '''XP-80A''', was designed for the larger [[General Electric]] [[Allison J33|I-40]] engine (an improved J31, later produced by Allison as the J33). Two aircraft (44-83021 and 44-83022) were built. 44-83021 was nicknamed the ''Gray Ghost'' after its "pearl gray" paint scheme, while 83022, left unpainted for comparison of flight characteristics, became known as the ''Silver Ghost''. The XP-80A's first test flight was unimpressive, but most of the problems with the design were soon addressed and corrected in the test program. Initial opinions of the XP-80A were not positive, with Lockheed Chief Engineering Test Pilot [[Milo Burcham]] commenting that an aircraft he very much enjoyed (powered by the Halford engine) had now become a "dog." The XP-80As were primarily testbeds for larger, more powerful engines and air intake design, and consequently were larger and 25% heavier than the XP-80.

The P-80 testing program proved very dangerous. Burcham was killed on 20 October 1944 while flying the third YP-80A, 44–83025. The ''Gray Ghost'' was lost on a test flight on 20 March 1945, although pilot [[Tony LeVier]] escaped. Newly promoted to chief engineering test pilot to replace Burcham, LeVier bailed out when one of the engine's turbine blades broke, causing structural failure in the aircraft's tail. LeVier landed hard and broke his back, but returned to the test program after six months of recovery.

The top-scoring World War II USAAF [[Flying ace|ace]] Major [[Richard Bong]] was also killed on an acceptance flight of a production P-80 in the United States on 6 August 1945. Both Burcham and Bong crashed as a result of main fuel pump failure. Burcham's death was the result of a failure to brief him on a newly installed emergency fuel pump backup system, but the investigation of Bong's crash found that he had apparently forgotten to switch on this pump, which could have prevented the accident. He bailed out when the aircraft rolled inverted but was too close to the ground for his parachute to deploy.

After Bong's death, both the USAAF and Lockheed wanted to prove the reliability of the airplane. [[Robert E. Thacker]] from the Flight Test Division at Wright Field was ordered to select three other pilots, pick up 5 P-80s from Lockheed and fly them to [[Edwards Air Force Base|Muroc Army Airbase]], and fly each airplane there for 500 hours. Thacker tapped [[Chuck Yeager]], plus two other pilots and they put 500 hours on each airplane without further incident.<ref>Col. Robert E. Thacker Interview Part 2 [https://www.youtube.com/watch?v=YW0w6lfYIlQ&t=2631 "Col. Robert E. Thacker Interview Part 2"]</ref>

After the war, the USAAF compared the P-80 and [[Messerschmitt Me 262|Me 262]] concluding, "Despite a difference in gross weight of nearly {{convert|2000|lb|kg|-2|abbr=on}}, the Me 262 was superior to the P-80 in acceleration, speed and approximately the same in climb performance. The Me 262 apparently has a higher [[critical Mach number]] (the Me 262A's [[Messerschmitt Me 262#High-speed research|being at M 0.86]]), from a drag standpoint, than any current Army Air Force fighter."<ref>Ethell and Price 1994, p. 180.</ref>