Editing Convair XF-92 (section)

==Design and development==

===Early work===
[[File:Convair XP-92 mockup.jpg|thumb|Mockup of the XP-92.]]
[[File:XF-92A Edwards AFB.jpg|thumb|The XF-92A at [[Edwards Air Force Base]], 1952]]
Prior to August 1945, the Vultee Division of Consolidated-Vultee looked at the possibility of a swept-wing aircraft powered by a ducted rocket. Years earlier, the company had performed designs which involved liquid-cooled radiator engines.  With this design, fuel would be added to the heat produced by small rocket engines in the duct, creating a "pseudo-[[ramjet]]".<ref name="J&L p. 122">Jenkins and Landis 2008, p. 122.</ref>

In August 1945, the [[United States Army Air Forces]] (USAAF), soon to be renamed the [[United States Air Force]], issued a proposal for a supersonic interceptor capable of {{convert|700|mi/h|km/h|abbr=on}} speeds and reaching an altitude of {{convert|50000|ft|m}} in four minutes.{{Citation needed|date=July 2011}} Several companies responded, among which was Consolidated-Vultee, which submitted its design on 13 October 1945.<ref name="J&L p. 122"/> This design featured swept wings and [[V-tail]]s, as well as a powerful propulsion system. Besides the ducted rocket, four {{Convert|1,200|lbf|kN}} rockets were positioned at the exhaust nozzle, along with the {{Convert|1,560|lbf|kN}} 19XB turbojet produced by Westinghouse.<ref name="J&L p. 122"/>

A proposal by [[Consolidated Vultee]] (later Convair) was accepted in May 1946, with a proposal for a ramjet-powered aircraft, with a 45° [[swept wing]] under USAAF [[Air Materiel Command]] Secret Project MX-813. However, [[wind tunnel]] testing demonstrated a number of problems with this design.<ref name=baugher>Baughe, r, Joe. [http://www.joebaugher.com/usaf_fighters/p92.html "Convair XF-92A."] ''USAF Fighters,'' 21 November 1999. Retrieved: 11 June 2011.</ref>

===Switch to delta===
Convair found that by straightening the trailing edge and increasing the sweep of the leading edge, the characteristics of their new wing were greatly improved. Thus, contrary to suggestions that German designer [[Alexander Lippisch]] influenced it, Convair independently discovered the thin high-speed delta wing.<ref name="hallion1979">Hallion (1979)</ref> Ralph Shick, chief of aerodynamic research, later met Lippisch at [[Wright-Patterson Air Force Base]]. This helped to convince him that the thin delta was the way forward, however the influence of Lippisch provided no more than "moral support" and Convair rejected many of his ideas, such as the thick wing of the [[Lippisch P.13a]] project and the [[Lippisch DM-1|DM-1]] test glider which the US had tested.<ref name=f102>[http://www.flightglobal.com/pdfarchive/view/1957/1957%20-%200510.html "Convair F-102"], ''Flight International'', pp. 512–518.</ref><ref name="hallion1979"/>

Thrust was to be provided by a {{convert|1560|lbf|abbr=on}} [[Westinghouse J30]] jet engine assisted by a battery of six {{convert|2000|lbf|kN|abbr=on}} liquid-fueled rockets. This mixed-propulsion system required a very large intake duct, which not only fed the jet engine but also passed air around the rocket exhaust to provide [[Air-augmented rocket|thrust augmentation]]. Located centrally, the large duct left nowhere to put a traditional cockpit; in its normal location it would have projected deep into the duct. To address this, the team modified the design in a fashion similar to both the [[Leduc 0.10]] and [[Miles M.52]], placing the cockpit in a cylindrical body in the center of the intake. The design was presented to the [[U.S. Air Force]] in 1946 and was accepted for development as the XP-92.<ref name="Yenne 2009, p. 27">Yenne 2009, p. 27.</ref>

===Delta research===
In order to gain inflight experience with the delta wing layout, Convair suggested building a smaller prototype, the '''Model 7002''', which the USAAF accepted in November 1946.<ref name="Taylor 1977, p. 61">Taylor 1977, p. 61.</ref>

In order to save development time and money, many components were taken from other aircraft; the main gear was taken from a  [[North American FJ-1 Fury]], the nosewheel from a [[Bell P-63 Kingcobra]], the engine and hydraulics were taken from a [[Lockheed P-80 Shooting Star]], the ejection seat and cockpit canopy were taken from the cancelled [[Convair XP-81]], and the rudder pedals were taken from a BT-13 trainer.

Construction was well underway at Vultee Field in [[Downey, California]] when [[North American Aviation]] took over the Vultee plants in summer 1947. The airframe was moved to Convair's plant in [[San Diego]], and completed in the autumn. In December it was shipped without an engine to [[NACA]]'s [[NASA Ames Research Center|Ames Aeronautical Laboratory]] for wind tunnel testing. After testing was completed, the airframe was returned to San Diego, where it was fitted with a {{convert|4250|lbf|abbr=on}} [[Allison J33]]-A-21 engine.<ref name="Yenne 2009, p. 27"/>

By the time the aircraft was ready for testing, the concept of the [[point-defense]] interceptor seemed outdated and the (now redesignated) F-92 project was cancelled; the test aircraft was nevertheless completed as the '''XF-92A'''.<ref name="Taylor 1977, p. 61"/>