Editing VTOL (section)

====Conventional design====
[[File:Rolls-Royce Thrust Measuring Rig science museum.jpg|thumb|left|"Flying Bedstead"- Rolls-Royce Thrust Measuring Rig]]

Another more influential early functional contribution to VTOL was [[Rolls-Royce Limited|Rolls-Royce]]'s [[Rolls-Royce Thrust Measuring Rig|Thrust Measuring Rig]] ("flying bedstead") of 1953. This led to the first VTOL engines as used in the first British VTOL aircraft, the [[Short SC.1]] (1957), Short Brothers and Harland, Belfast which used four vertical lift engines with a horizontal one for forward thrust.

[[File:Short SC.1.jpg|thumb|The Short SC.1 a VTOL delta aircraft]]

The [[Short SC.1]] was the first British fixed-wing VTOL aircraft. The SC.1 was designed to study the problems with VTOL flight and the transition to and from forward flight. The SC.1 was designed to meet a Ministry of Supply (MoS) request for tender (ER.143T) for a vertical take-off research aircraft issued in September 1953. The design was accepted by the ministry and a contract was placed for two aircraft (XG900 and XG905) to meet Specification ER.143D dated 15 October 1954. The SC.1 was also equipped with the first "fly-by-wire" control system for a VTOL aircraft. This permitted three modes of control of the aerodynamic surfaces or the nozzle controls.

The [[Republic Aviation]] [[Republic AP-100|AP-100]] was a prototype VTOL 6x [[General Electric J85]] turbojet-engined nuclear-capable strike fighter concept designed by [[Alexander Kartveli]] that had three ducted fans in the centre of its fuselage and tail as a possible contender for the [[TFX Program]].<ref>Project Hummingbird (Technical Report) A Technical Summary and Compilation of Characteristics and Specifications on Steep-Gradient Aircraft, Volume 88, April 1961. By United States Federal Aviation Agency. Page 143–144, Figure 175.</ref><ref>Air Progress History of Aviation Spring 1961 edition</ref><ref>Aviation Week and Space Technology, Lift-Fan Tests Show VTOL Potential. August 8, 1960</ref> Another design was the A400 AVS that used variable-geometry wings but was found too complicated; however, it led to the development of the [[AFVG]], which in turn helped the development of the [[Panavia Tornado]].

[[File:Yak-38 Lift Engines NT.PNG|thumb|left|The [[Soviet Union]]'s VTOL aircraft, the [[Yakovlev Yak-38]]]]

The [[Yakovlev Yak-38]] was a [[Soviet Navy]] VTOL aircraft intended for use aboard their light carriers, cargoships, and capital ships. It was developed from the [[Yakovlev Yak-36]] experimental aircraft in the 1970s. Before the Soviet Union broke up, a supersonic VTOL aircraft was developed as the Yak-38's successor, the [[Yakovlev Yak-141|Yak-141]], which never went into production.<ref>{{Cite web|title=Vertical take-off/landing aircraft: Yak-38|url=http://www.yak.ru/ENG/FIRM/HISTMOD/yak-38.php|access-date=2021-04-29|website=www.yak.ru|publisher=[[Yakovlev|Yakovlev Design Bureau]]|date=16 July 2008}}</ref>

[[File:Aircraft VJ101C top.jpg|thumb|A German V/[[STOL]] [[EWR VJ 101|VJ101]] on display at the [[Deutsches Museum]], [[Munich, Germany]] ]]
[[File:Do-31 2.jpg|thumb|[[Dornier Do 31|Do 31 E3]] on display at the [[Deutsches Museum]], Germany]]

In the 1960s and early 1970s, Germany planned three different VTOL aircraft. One used the [[Lockheed F-104 Starfighter]] as a basis for research for a [[V/STOL]] aircraft. Although two models (X1 and X2) were built, the project was canceled due to high costs and political problems as well as changed needs in the [[German Air Force]] and NATO. The [[EWR VJ 101]]C did perform free VTOL take-offs and landings, as well as test flights beyond mach 1 in the mid- and late 60s. One of the test aircraft is preserved in the [[Deutsches Museum]] in Munich, Germany, another outside Friedrichshafen Airport. The others were the VFW-Fokker [[VFW VAK 191B|VAK 191B]] light fighter and reconnaissance aircraft, and the [[Dornier Do 31]]E-3 (troop) transport.<ref>Jackson 1976, p. 143.</ref>

The [[LLRV]] was a [[spacecraft]] simulator for the Apollo lunar lander.<ref>{{Cite web|title=NASA - NASA Dryden Technology Facts - Lunar Landing Research Vehicle|url=https://www.nasa.gov/centers/dryden/about/Organizations/Technology/Facts/TF-2004-08-DFRC.html|access-date=2021-04-29|website=www.nasa.gov|language=en|archive-date=2018-12-23|archive-url=https://web.archive.org/web/20181223163609/https://www.nasa.gov/centers/dryden/about/Organizations/Technology/Facts/TF-2004-08-DFRC.html|url-status=dead}}</ref> It was designed to mimic the flight characteristics of the [[Apollo Lunar Module|lunar exploration module]] (LEM), which had to rely on a reaction engine to land on the Moon.

The idea of using the same engine for vertical and horizontal flight by altering the path of the thrust was conceived by [[Michel Wibault]].<ref name="Pegasus">{{cite book |last1=Dow |first1=Andrew |title=Pegasus: The Heart of the Harrier |date=2009 |publisher=Pen & Sword Aviation |location=Barnsley, South Yorkshire, UK |isbn=978-1-84884-042-3 |pages=29–46 |url=https://books.google.com/books?id=qTLAAwAAQBAJ |access-date=13 June 2020}}</ref> It led to the [[Bristol Siddeley Pegasus]] engine which used four rotating [[nozzle]]s to direct thrust over a range of angles.<ref>{{cite book|chapter-url=http://www.engineering108.com/Data/Engineering/aeronautical_engineering/Basics-of-Aeronautics.pdf |chapter=Airfoil |title=Basics of Aeronautics|access-date=24 May 2015}}</ref> This was developed side-by-side with an airframe, the [[Hawker P.1127]], which became subsequently the Kestrel and then entered production as the [[Hawker Siddeley Harrier]], though the supersonic [[Hawker Siddeley P.1154]] was canceled in 1965. The French in competition with the P.1154 had developed a version of the [[Dassault Mirage III]] capable of attaining [[Mach Number|Mach]] 1. The [[Dassault Mirage IIIV]] achieved transition from vertical to horizontal flight in March 1966, reaching Mach 1.3 in level flight a short time later.