The Vought YA-7F "Strikefighter" is a prototype transonic
attack aircraft
An attack aircraft, strike aircraft, or attack bomber is a tactical military aircraft that has a primary role of carrying out airstrikes with greater precision than bombers, and is prepared to encounter strong low-level air defenses while pre ...
based on the subsonic
A-7 Corsair II
The LTV A-7 Corsair II is an American carrier-capable subsonic light attack aircraft designed and manufactured by Ling-Temco-Vought (LTV).
The A-7 was developed during the early 1960s as replacement for the Douglas A-4 Skyhawk. Its design was ...
. Two prototypes were converted from A-7Ds. The YA-7F was not ordered into production, its intended role being filled by the
F-16 Fighting Falcon
The General Dynamics F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successful ...
.
Design and development
In 1985, the USAF requested proposals for a fast strike aircraft because of concerns that
A-10 Thunderbolt II
The Fairchild Republic A-10 Thunderbolt II is a single-seat, twin-turbofan, straight-wing, subsonic attack aircraft developed by Fairchild Republic for the United States Air Force (USAF). In service since 1976, it is named for the Republic ...
was too slow for interdiction. The design called for a new engine, either the
Pratt & Whitney F100
The Pratt & Whitney F100 (company designation JTF22) is an afterburning turbofan engine manufactured by Pratt & Whitney that powers the F-15 Eagle and F-16 Fighting Falcon.
Development
In 1967, the United States Navy and United States Air Force ...
-PW-220 or
General Electric F110
The General Electric F110 is an afterburning turbofan jet engine produced by GE Aviation. The engine is derived from the General Electric F101 and shares its core design, and primarily powers tactical fighter aircraft. The F118 is a non-afterbu ...
-GE-100. LTV responded with the YA-7F, a supersonic version of A-7 powered by an F100-PW-220 with 26,000 lbf (116 kN) thrust. During the development process,
Aviation Week & Space Technology
''Aviation Week & Space Technology'', often abbreviated ''Aviation Week'' or ''AW&ST'', is the flagship magazine of the Aviation Week Network. The weekly magazine is available in print and online, reporting on the aerospace, defense and aviati ...
magazine reported that, early on, LTV also experimented with adapting the afterburner from an F100-PW-220 to the existing
Allison TF41
The Allison TF41 (Company designations RB.168-62 and Model 912) is a low-bypass turbofan engine.
Design and development
The TF41 was jointly developed by Allison Engine Company and Rolls-Royce from the latter's RB.168-25R Spey. Allison manufac ...
engine. Because the TF41 had a higher bypass ratio, the addition of the afterburner produced a much higher thrust (26,000lbf) than the F100 could produce (which was 23,770lbf), while retaining the greater fuel economy of the TF41. To accommodate the longer engine, the fuselage was lengthened about 4 ft (1.22 m). New fuselage sections were inserted in both the forward and aft fuselage – a 30 in (76 cm) section in front of the wing and an 18 in (46 cm) section behind the wing. The reasons were three-fold: (1) to accommodate engine length issues, (2) to accommodate aerodynamic issues with shape, and (3) to accommodate weight distribution issues. The increase in internal volume allowed for more fuel and other stores improvements. The wing was strengthened and fitted with new augmented flaps, leading edge extensions and automatic maneuvering flaps.
![445th Flight Test Squadron YA-7F Corsair IIs with ED A-7D](https://upload.wikimedia.org/wikipedia/commons/c/cf/445th_Flight_Test_Squadron_YA-7F_Corsair_IIs_with_ED_A-7D.jpg)
The vertical stabilizer height was increased about 10 in (25 cm), the unit horizontal tail was flipped from dihedral to anhedral, and control surfaces were flattened. The end result resembled the supersonic
F-8 Crusader
The Vought F-8 Crusader (originally F8U) is a single-engine, supersonic, carrier-based air superiority jet aircraft built by Vought for the United States Navy and United States Marine Corps (replacing the Vought F7U Cutlass), and for the Frenc ...
from which the original subsonic A-7 was derived. Many of the vehicle systems and mission systems were heavily modified and upgraded with leading edge technology, including a Molecular Sieve Oxygen Generating System and better cockpit displays. Low Altitude Night Attack Systems, an improved HUD and many software enhancements for navigation and weapons delivery were planned and being designed concurrently by Vought Dallas.
The new supersonic A-7 could accelerate with a bomb load from 400 to in under 15 seconds and could sustain Mach 1.2 for longer times with the extra fuel. The YA-7F modifications allowed 7-g turn and burn capability that permitted high-speed sustained evasive maneuvers plus great improvements in high angle of attack performance. As a CAS/BAI platform to penetrate into enemy territory and return safely, the "Strikefighter" moniker was most fitting. Two A-7Ds were extensively modified, the first one flying on 29 November 1989, and breaking the
sound barrier
The sound barrier or sonic barrier is the large increase in aerodynamic drag and other undesirable effects experienced by an aircraft or other object when it approaches the speed of sound. When aircraft first approached the speed of sound, th ...
on its second flight. The second prototype flew on 3 April 1990.
The project was canceled due to improved relations with former adversaries, lower defense budgets, and the
Air National Guard
The Air National Guard (ANG), also known as the Air Guard, is a federal military reserve force of the United States Air Force, as well as the air militia of each U.S. state, the District of Columbia, the Commonwealth of Puerto Rico, and the ter ...
, by then the principal US operator of the A-7, generally favoring the in-production
F-16 Fighting Falcon
The General Dynamics F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successful ...
.
Variants
![445th Flight Test Squadron YA-7F Corsair II 70-1039 static display](https://upload.wikimedia.org/wikipedia/commons/8/8c/445th_Flight_Test_Squadron_YA-7F_Corsair_II_70-1039_static_display.jpg)
;YA-7F (A-7D Plus / A-7 Strikefighter)
:Stretched, supersonic version of A-7 powered by a
Pratt & Whitney F100
The Pratt & Whitney F100 (company designation JTF22) is an afterburning turbofan engine manufactured by Pratt & Whitney that powers the F-15 Eagle and F-16 Fighting Falcon.
Development
In 1967, the United States Navy and United States Air Force ...
-220 turbofan, optimized for interdiction role, but cancelled after only two were built.
Operators
;
*
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
Aircraft on display
*70-1039 –
Hill Aerospace Museum
Hill Aerospace Museum is a military aviation museum located at Hill Air Force Base in Roy, Utah. It is dedicated to the history of the base and aviation in Utah.
History
Preparations for a museum began in 1984, when ground was broken on an "Ae ...
,
Hill AFB
Hill Air Force Base is a major U.S. Air Force (USAF) base located in northern Utah, just south of the city of Ogden, and bordering the Cities of Layton, Clearfield, Riverdale, Roy, and Sunset with its largest border immediately adjacent to ...
,
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
.
*71-0344 –
Air Force Flight Test Center Museum
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for ...
,
Edwards AFB
Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, but its eastern end is in San Bernardino County and a southern arm is in Los Angeles County. The hub of the base is Ed ...
,
California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
.
"YA-7F Strikefighter/70-1039."
''Air Force Flight Test Center Museum.'' Retrieved: 26 January 2022.
Specifications (YA-7F)
See also
References
Notes
Bibliography
*NAVAIR 01-45AAA-1, A-7A/B Flight Manual. US Navy, 15 August 1973.
*NAVAIR 01-45AAE-1, A-7C/E Flight Manual. US Navy, 1 March 1973.
*Donald, David and Jon Lake, eds. ''Encyclopedia of World Military Aircraft''. London: AIRtime Publishing, 1996. .
*Dorr, Robert F. "A Plus for the Corsair". ''Air International
''AIR International'' is a British aviation magazine covering current defence aerospace and civil aviation topics. It has been in publication since 1971 and is currently published by Key Publishing Ltd.
History and profile
The magazine was fir ...
'', August 1987, Vol 33 No. 2. Bromley, UK:Fine Scroll. . pp. 61–65, 84–87, 93.
*Higham, Robin and Carol Williams. ''Flying Combat Aircraft of USAAF-USAF (Volume 2)''. Andrews AFB, Maryland: Air Force Historical Foundation, 1978. .
*Hobson, Chris. ''Vietnam Air Losses, USAF/USN/USMC, Fixed-Wing Aircraft Losses in Southeast Asia, 1961–1973''. North Branch, Minnesota: Specialty Press, 2001. .
*Swanborough, Gordon and Peter M. Bowers. ''United States Military Aircraft Since 1909''. Washington, DC: Smithsonian Books, 1989. .
*Swanborough, Gordon and Peter M. Bowers. ''United States Navy Aircraft Since 1911''. London: Putnam, Second edition, 1976. .
*Swanborough, Gordon and Peter M. Bowers. ''United States Navy Aircraft Since 1911''. Annapolis, Maryland: Naval Institute Press, 1990. .
Wings of Eagles
External links
YA-7F Prototype at Hill AFB Museum
* Joe Baugher's website on th
{{US attack aircraft
A-7F Strikefighter
1980s United States attack aircraft
Single-engined jet aircraft
High-wing aircraft
Cancelled military aircraft projects of the United States
Aircraft first flown in 1989