Military


A-7 Corsair II

The Corsair II was developed in response to a Navy requirement for a single-place, fair-weather subsonic attack aircraft capable of carrying a much heavier weapons load than the Douglas A-4 Skyhawk. The A-7 underwent a number of modifications since its 1965 introduction. First flight of the new aircraft (Vought A-7D) took place on September 27, 1965, and it was in production since then with a total of 1534 units produced by mid-1980. In addition to the Navy and Marine Corps, the USAF as well as air forces of two other nations operate the A-7. The definitive versions of the aircraft are the USAF A-7D and the closely related Navy A-7E.

The A-7A was a single-place, carrier-based, light attack, subsonic, medium range aircraft powered by the Pratt & Whitney TF30-P-6 engine and designed to provide high attack utility and flexibility for close support and interdiction missions by virtue of a large number of external store stations to provide ordnance loading capacity and freedom of ordnance choice. A large internal fuel capacity made external fuel unnecessary for most missions while retaining maximum number of stations for armament. The A-7A's combat range was not less than 1,180 nautical miles with an average cruising speed never under 390 knots. The aircraft had an excellent overload capability in terms of wind-over-deck requirements, flying qualities and structural integrity. Features to expedite maintenance and airplane turnaround were important A-7A design characteristics. The A-7A was designed with a fixed wing incidence and a high-lift system composed of leading edge flaps and single slotted trailing edge flaps. Lateral control was provided by outboard ailerons and inboard spoilers.

The A-7B was similar to A-7A except with improved engine, a Pratt & Whitney TF30-P-8 or -408, instead of the TF30-P-6 used in the A-7A. Engine thrust was increased to 12,200 lbs in the A-7B with this advanced P&W engine. Also, variable position flaps, not found in the A-7A, were incorporated in the A-7B.

The A-7C was initially intended to be a two-seat training version of the A-7B. When this plan was not pursued, the A-7C designation served as a "stop-gap" assigned to those aircraft accepted with the improvements intended for aircraft accepted as A-7E but lacking the Rolls Royce TF41-A-2 engine intended for the A-7E. All A-7Cs were powered by either the Pratt & Whitney TF30-P-8 or -408.

The TA-7C was a two-seat trainer version, converted from A-7B and A-7C. Sixty early A-7B/A-7E airframes were converted to a two-seat advanced trainer derivative with full operational capability and designated as the TA-7C.

The A-7D was built for the U.S. Air Force. Defense Secretary McNamara directed the Air Force to acquire a version of the Navy's A-7 attack airplane, reflecting his view that the Air Force needed to strengthen its close-air-support (CAS) commitment to the Army. The aging low-payload F-100 was the Air Force's primary air-to-ground CAS airplane at the time. Initially, the lightweight Northrop N-156F (the F-5) was a possible candidate to replace the F-100. But by late 1965 the Air Force had decided that the A-7 was better than the F-5 for the battlefield support role because of its much greater payload. The A-7 Corsair II was used by TAC for close air support attack missions. The A-7D version was used for a number of years, mostly by the ANG, until phased out in the early 1990s.

The original power plant of the A-7 was a nonafterburning version of the Pratt & Whitney TF30 turbofan. This is the same engine that, equipped with an afterburner, powers both the F-111 and the F-14. Beginning with the A-7D, however, the more powerful Allison TF41-A-1 turbofan was installed. An American-made version of the British Rolls-Royce Spey, the TF41-A-1 has a bypass ratio of 0.7 and uses a five-stage fan. Engine thrust was increased to to 14,250 lbs in the the A-7D with the Allison-built Rolls-Royce Spey engine, which was also utilized by the Navy in the A-7E.

Although the A-7 was originally intended as a fair-weather aircraft, later versions (beginning with the A-7D) were equipped with extensive electronic gear for all-weather operations. The gross weight of the A-7D is a little more than twice that of the A-4E but is significantly less than that of the A-6E. Maximum speed of the A-7D is as 663 miles [402] per hour (Mach 0.89) at an altitude of 7000 feet. Stalling speed at maximum gross weight is a very high 174 miles per hour. For landing on an aircraft carrier following a mission, however, a weight much less than the maximum value, along with a reduction in stalling speed, would normally be expected. For example, with a weight of 23 000 pounds, the stalling speed would be about 135 miles per hour.

The A-7E (whose procurement ended in 1983) was the final fleet version of the A-7. The A-7E had a 20mm M-61 multi-barrel gun and could carry payloads of up to 15,000 pounds of bombs and missiles on eight ordnance stations. The A-7E incorporated greatly improved avionics [including heads-up display], an improved hydraulic system and anti-skid brakes. The A-7E was similar to A-7B but with improved naval weapons delivery system, the AVQ-7B Head-Up Display, the ASN-91 Tactical Computer, the APQ-126 Forward Looking Radar, the ASN-90 Inertial Measurement Set and one 20 mm M61Al gun instead of two 20 mm MK-12 guns. All A-7Es were powered by the Rolls Royce TF41-A-2 engine built, with modifications under license by Allison division of General Motors. The TF41, a non-afterburner engine, had a thrust of 15,000 pounds which was a considerable increase over the TF30-P-8 and -408. The A-7E made its combat debut when VA-146 and VA-147 deployed in April 1970 in America (CVA 66).

The A-7G was the designation of aircraft for Switzerland, which were never delivered.

The A-7H was built for Greece.

The TA-7H is the two-seat trainer version of A-7H for Greece.

The A-7K was a two-seat A-7D for U.S. Air Force.

The EA-7L was converted from TA-7C; modified to FEWSG configurations.

The A-7P, for Portugal, was converted from A-7A.

The TA-7P is a two-seat trainer version for Portugal, converted from A-7A.

Approximately 1,500 A-7's, of various configurations, were produced for the US Navy and US Air Force, as well as new production aircraft for the Hellenic Air Force. At the peak of utilization, 22 Navy squadrons were equipped with the A-7E. Transition of some of these units to the F/A-18 Hornet began in 1987. After more than two decades of service, the Corsair was replaced by the F/A-18 Hornet in the carrier air wing mix, with the last two squadrons transitioned in FY 1992. Replacing A-7s with F/A-18s gave operational commanders more flexibility by allowing them to employ the F/A-18s in either the fighter or attack role. Also, a smaller number of aircraft (85) were needed in an F/A-18 equipped carrier air wing than in an A-7E equipped carrier air wing (94).

The A-7 remains in operation by Foreign Military Sales (FMS) customers. Several hundred A-7's remain in storage and are available for sale to international military customers. A number of countries, including Greece, Portugal and Thailand have bought surplus A-7s, all of them Navy versions. The aircraft are supported by Northrop Grumman's Aircraft Modification and Overhaul Programs organization. The company provides technical modifications and sales support services to the U.S. Naval Air Systems Command for the international effort, as well as customer integration, training, and support services for the aircraft. The A-7 Corsair II is a single-place, fighter-attack airplane that can perform a variety of missions including close-air support, long-range strike and interdiction, coastal defense and surveillance, search-and-rescue and air cover, reconnaissance, escort, and tanker operations.



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