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24-439: Although this system is costlier than alternative methods, it provides greater flexibility in carrier operations, since it imposes less onerous design elements on fixed wing aircraft than alternative methods of launch and recovery such as STOVL or STOBAR , allowing for a greater payload for more ordnance and/or fuel. CATOBAR can launch aircraft that lack a high thrust to weight ratio , including heavier non-fighter aircraft such as

48-435: A STOBAR ski jump ramps . STOVL A short take-off and vertical landing aircraft ( STOVL aircraft ) is a fixed-wing aircraft that is able to take off from a short runway (or take off vertically if it does not have a heavy payload) and land vertically (i.e. with no runway). The formal NATO definition (since 1991) is: A Short Take-Off and Vertical Landing aircraft is a fixed-wing aircraft capable of clearing

72-480: A 15 m (50 ft) obstacle within 450 m (1,500 ft) of commencing take-off run, and capable of landing vertically. On aircraft carriers , non-catapult-assisted fixed-wing short takeoffs are accomplished with the use of thrust vectoring , which may also be used in conjunction with a runway " ski-jump ". There are 14 aircraft carriers that operate these STOVL aircraft: United States (9), United Kingdom (2), Italy (2), and Spain (1). Use of STOVL tends to allow aircraft to carry

96-703: A larger payload compared to vertical take-off and landing (VTOL), while still only requiring a short runway. The most famous examples are the Hawker Siddeley Harrier and the BAe Sea Harrier . Although technically a V/STOL aircraft, they are operationally STOVL aircraft due to the extra weight carried at take-off for fuel and armaments. The same is true of the B variant of the Lockheed Martin F-35 Lightning II , which demonstrated VTOL capability in test flights but

120-750: A lift fan; all methods had an aft vectoring nozzle for the main engine. ASTOVL would continue under the Common Affordable Lightweight Fighter (CALF) program, which eventually became part of the Joint Strike Fighter program ; the Lockheed Martin X-35B with the SDLF was eventually selected for full-scale development in 2001, with the production aircraft for operational service becoming the F-35B with

144-830: Is found on the American Gerald R. Ford -class carriers (the electromagnetic aircraft launch system ) and the Chinese carrier Fujian . Following the decommissioning of Brazil's NAe São Paulo in February 2017, only three states currently operate carriers that use the CATOBAR system: the U.S. with its Nimitz -class and Gerald R. Ford -class , France with its Charles De Gaulle , and China with its Type-003 Fujian . United States Navy People's Liberation Army Navy The Chinese Fujian (Type 003) features an integrated electric propulsion system that will allow

168-589: Is operationally a STOVL. In 1951, the Lockheed XFV and the Convair XFY Pogo tailsitters were both designed around the Allison YT40 turboprop engine driving contra-rotating propellers . The British Hawker P.1127 took off vertically in 1960, and demonstrated conventional take-off in 1961. It was developed into the Hawker Siddeley Harrier which flew in 1967. In 1962, Lockheed built

192-632: The Armstrong Whitworth AW.681 cargo aircraft was under development when cancelled in 1965. The Dornier Do 31 got as far as three experimental aircraft before cancellation in 1970. Although mostly a VTOL design, the Bell Boeing V-22 Osprey has increased payload when taking off from a short runway. Lockheed XFV The Lockheed XFV (sometimes referred to as the " Salmon ") is an American experimental tailsitter prototype aircraft built by Lockheed in

216-576: The E-2 Hawkeye and Grumman C-2 Greyhound . The catapult system in use in most modern CATOBAR carriers is the steam catapult . Its primary advantage is the amount of power and control it can provide. During World War II the US Navy used a hydraulic catapult. The United States and China are completing the development of electromagnetic catapult to launch carrier-based aircraft using a linear motor drive instead of steam. The electromagnetic catapult

240-571: The F135-PW-600 engine. NASA uses the abbreviation SSTOVL for Supersonic Short Take-Off / Vertical Landing, and as of 2012, the X-35B/F-35B are the only aircraft to conform with this combination within one flight. The experimental Mach 1.7 Yakovlev Yak-141 did not find an operational customer, but similar rotating rear nozzle technology is used on the F-35B which entered service on 31 July 2015. Larger STOVL designs were considered,

264-681: The XV-4 Hummingbird for the U.S. Army . It sought to "augment" available thrust by injecting the engine exhaust into an ejector pump in the fuselage. First flying vertically in 1963, it suffered a fatal crash in 1964. It was converted into the XV-4B Hummingbird for the U.S. Air Force as a testbed for separate, vertically mounted lift engines, similar to those used in the Yakovlev Yak-38 'Forger'. That plane flew and later crashed in 1969. The Ryan XV-5 Vertifan , which

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288-466: The " pogo stick " (a direct reference to the rival Convair XFY 's name). To begin flight testing, a temporary non-retractable undercarriage with long braced V-legs was attached to the fuselage, and fixed tail wheels attached to the lower pair of fins. In this form, the aircraft was trucked to Edwards AFB in November 1953 for ground testing and taxiing trials. During one of these tests, at a time when

312-601: The 1950s to 1980s, only the subsonic Hawker Siddeley Harrier and Yak-38 Forger reached operational status, with the Forger being withdrawn after the fall of the Soviet Union . Rockwell International built, and then abandoned, the Rockwell XFV-12 supersonic fighter which had an unusual wing which opened up like window blinds to create an ejector pump for vertical flight. It never generated enough lift to get off

336-782: The Mirage IIIV for use in NATO, was cancelled even as the aircraft were being built. In 1983, the Defense Advanced Research Projects Agency ( DARPA ) initiated the Advanced STOVL (ASTOVL) program to develop a supersonic STOVL fighter (SSF) to replace the Harrier for the U.S. Marine Corps and the U.K. Royal Navy. Several propulsion methods were explored under ASTOVL and assigned to different contractors for research and development. These include

360-635: The Shaft-Driven Lift Fan (SDLF) by Lockheed which had a forward lift fan powered by a shaft connected to the main engine's low-pressure spool and engaged by a clutch, the Lift-Plus-Lift/Cruise (LPLC) by Northrop (later Northrop Grumman ) which had a separate dedicated lift engine alongside the main engine, and the Gas-Driven Lift Fan (GDLF) by McDonnell Douglas that used the main engine bleed air to power

384-574: The XFV's top speeds would be eclipsed by contemporary fighters and that only highly experienced pilots could fly the aircraft, the project was cancelled in June 1955. Salmon taxied the XFV-1 on its temporary gear "from a standing start to 175 mph, and then brought it back down to a dead stop without any use of the brakes, all within a distance of one mile." The single flying prototype ended up as an exhibit at

408-408: The aft section of the large spinner had not yet been fitted, Lockheed chief test pilot Herman "Fish" Salmon managed to taxi the aircraft past the liftoff speed, and the aircraft made a brief hop on 22 December 1953. The official first flight took place on 16 June 1954. Full VTOL testing at Edwards AFB was delayed pending the availability of the 7,100 shp Allison T54 , which never materialized. After

432-402: The brief unintentional hop, the aircraft made a total of 32 flights. All further XFV-1 flights did not involve any vertical takeoffs or landings. The XFV-1 was able to make a few transitions in flight from the conventional to the vertical flight mode and back, and had briefly held in hover at altitude. Performance remained limited by the confines of the flight test regime. With the realization that

456-403: The early 1950s to demonstrate the operation of a vertical takeoff and landing (VTOL) fighter for protecting convoys. The Lockheed XFV originated as a result of a proposal issued by the U.S. Navy in 1948 for an aircraft capable of vertical takeoff and landing (VTOL) aboard platforms mounted on the afterdecks of conventional ships. Both Convair and Lockheed competed for the contract but in 1950,

480-536: The ground despite developing 20,000 lbf of thrust. The French had a nominally Mach 2 Dassault Mirage IIIV fitted with no less than 8 lift engines that flew (and crashed), but did not have enough space for fuel or payload for combat missions. The German EWR VJ 101 used swiveling engines mounted on the wingtips with fuselage mounted lift engines, and the VJ 101C X1 reached supersonic flight (Mach 1.08) on 29 July 1964. The supersonic Hawker Siddeley P.1154 , which competed with

504-688: The operation of electromagnetic catapults , similar to the Electromagnetic Aircraft Launch System (EMALS) used by the United States Navy . INS Vishal , India's second indigenous aircraft carrier of the Vikrant -class , is planned to be of 65,000 ton displacement and to utilize the EMALS catapults developed by General Atomics , as it supports heavier fighters, AEW aircraft and UCAVs that cannot launch using

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528-474: The requirement was revised, with a call for a research aircraft capable of eventually evolving into a VTOL ship-based convoy escort fighter. On 19 April 1951, two prototypes were ordered from Lockheed under the designation XFO-1 (company designation was Model 081-40-01). Soon after the contract was awarded, the project designation changed to XFV-1 when the Navy's code for Lockheed was changed from O to V. The XFV

552-475: Was also built for the U.S. Army at the same time as the Hummingbird, experimented with gas-driven lift fans. That plane used fans in the nose and each wing, covered by doors which resembled half garbage can lids when raised. However, it crashed twice, and proved to generate a disappointing amount of lift, and was difficult to transition to horizontal flight. Of dozens of VTOL and V/STOL designs tried from

576-406: Was powered by a 5,332 hp (3,976 kW) Allison YT40 -A-6 turboprop engine driving three-bladed contra-rotating propellers . The tail surfaces were a reflected cruciform v-tail (forming an x ) that extended above and below the fuselage. The aircraft had an ungainly appearance on the ground with a makeshift, fixed landing gear attached. Lockheed employees derisively nicknamed the aircraft

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