A-7 Corsair II…
- The Ling-Temco-Vought A-7 Corsair II is a carrier-capable subsonic light attack aircraft introduced to replace the Douglas A-4 Skyhawk. The A-7 airframe design was based on the successful supersonic Vought F-8 Crusader. It was one of the first combat aircraft to feature a head-up display (HUD), an inertial navigation system (INS), and a turbofan engine.
- The Corsair II initially entered service with the United States Navy during the Vietnam War. It was later adopted by the United States Air Force, including the Air National Guard, to replace the Douglas A-1 Skyraider, North American F-100 Super Sabre and Republic F-105 Thunderchief. The aircraft was also exported to Greece in the 1970s, and Portugal in the late 1980s. / A-7 Corsair II /
A-7 Corsair II: Design And Development…
- In 1962, the United States Navy began preliminary work on VAX (Heavier-than-air, Attack, Experimental), a replacement for the A-4 Skyhawk with greater range and payload. A particular emphasis was placed on accurate delivery of weapons to reduce the cost per target. The requirements were finalized in 1963, announcing the VAL (Heavier-than-air, Attack, Light) competition. The USAF philosophy was to employ only supersonic fighter-bombers such as the F-105 Thunderchief and F-100 Super Sabre. However, the Navy felt that a subsonic design could carry the most payload the farthest distance, due to the lower fuel burn rate from avoiding supersonic flight. The first A-7 mock-up in 1964. / A-7 Corsair II /
- To minimize costs, all proposals had to be based on existing designs. Vought, Douglas Aircraft, Grumman and North American Aviation responded. The Vought proposal was based on the successful F-8 Crusader fighter, having a similar configuration, but shorter and more stubby, with a rounded nose. It was selected as the winner on 11 February 1964, and on 19 March the company received a contract for the initial batch of aircraft, designated A-7. In 1965, the aircraft received the popular name Corsair II, after Vought’s highly successful F4U Corsair of World War II. (There was also a Vought O2U Corsair biplane scout and observation aircraft in 1920s.) / A-7 Corsair II/
- The aircraft was fitted with an AN/APQ-116 radar, later followed by the AN/APQ-126, which was integrated into the ILAAS digital navigation system. The radar also fed a digital weapons computer which made possible accurate delivery of bombs from a greater stand-off distance, greatly improving survivability compared with faster platforms such as the F-4 Phantom II. It was the first U.S. aircraft to have a modern head-up display, (made by Marconi-Elliott), now a standard instrument, which displayed information such as dive angle, airspeed, altitude, drift and aiming reticle. The integrated navigation system allowed for another innovation – the projected map display system (PMDS) which accurately showed aircraft position on two different map scales.
- The A-7 had a fast and smooth development. The YA-7A made its first flight on 27 September 1965, and began to enter Navy squadron service late in 1966. The first Navy A-7 squadrons reached operational status on 1 February 1967, and began combat operations over Vietnam in December of that year. / A-7 Corsair II /
- The A-7′s integrated weapons computer provided highly accurate bombing with CEP of 60 ft (20 m) regardless of pilot experience. When Vought technical representatives were available to “tweak” the inertial systems, the CEP was often less than five meters for experienced fleet aviators. The inertial navigation system required a mere 2.5 minutes on the ground for partial (coarse) alignment, a big improvement over 13 minutes required in F-4 Phantom II. For newly manufactured E models, the A-7 required only 11.5 man hours of maintenance per mission resulting in quick turnaround and high number of combat-ready aircraft. However, after several years of exposure to the harsh marine conditions aboard aircraft carriers, the maintenance hours per sortie were often twice this amount. / A-7 Corsair II /
- The A-7 offered a plethora of leading-edge avionics compared to contemporary aircraft. This included data link capabilities that, among other features, provided fully “hands-off” carrier landing capability when used in conjunction with its approach power compensator (APC) or auto throttle. Other notable and highly advanced equipment was a projected map display located just below the radar scope. The map display was slaved to the inertial navigation system and provided a high-resolution map image of the aircraft’s position superimposed over TPC/JNC charts. Moreover, when slaved to the all-axis auto pilot, the inertial navigation system could fly the aircraft “hands off” to up to nine individual way points. Typical inertial drift was minimal for newly manufactured models and the inertial measurement system accepted fly over, radar, and TACAN updates. / A-7 Corsair II /
A-7 Corsair II: Improved Versions…
- Secretary of Defense Robert McNamara prodded the Air Force to adopt not only the hugely successful F-4, but also the Navy’s A-7 Corsair as a low-cost follow-on to F-105s until the troubled F-111 became operationally available, and as a close-air support replacement for the Douglas A-1 Skyraider. On 5 November 1965, the USAF announced that it would purchase a version of the A-7, designated the A-7D, for Tactical Air Command. The Air Force ordered the A-7D with a fixed high speed refueling receptacle behind the pilot optimized for the KC-135′s flying boom rather than the folding long probe of the Navy aircraft. The most important difference from the preceding Navy versions was the adoption of the Allison TF41-A-1 turbofan, a license-built version of the British Rolls-Royce Spey.
- With 14,500 lbf (64.5 kN) of thrust, the engine offered a considerable boost in performance. The M61 Vulcan cannon was selected in place of the twin single-barrel 20 mm cannon. In addition, avionics were upgraded. The YA-7D prototype with TF30 flew on 6 April 1968, with the first TF41 aircraft taking to the air on 26 September 1968. The aircraft were later updated to carry the Pave Penny laser spot tracker to add the capability to drop guided bombs. A total of 459 were built and assigned to tactical fighter wings of the Tactical Air Command (TAC). / A-7 Corsair II /
- The Navywas so impressed with the performance gain of the USAF A-7D that they ordered their own version with the TF41 engine and M61 cannon, the A-7E, to go along with the new continuous solution weapon systems and sophisticated avionics that was developed in the A-7C model that was highly advanced for that era. The first prototype flew on 25 November 1968. A-7Es were built in the 1970s with outstanding mission success in the fleet. In 1979 the first around-the-clock night-attack FLIR-capable aircraft were delivered to VA-81 at NAS Cecil Field, Florida and VA-22 at NAS Lemoore, California. These aircraft were fitted with a fixed FLIR pod on the right inboard wingstation which broadcast temperature discriminating images through the HUD. During the 1980s, when defense budgets finally allowed, funding for various system upgrades and engineering change proposal mods were incorporated to increase reliability, safety and mission effectiveness. Several squadrons of Navy A-7Es received night attack capability in early 1980s. / A-7 Corsair II/
- Production of Corsairs continued through 1984, yielding a total of 1,569 aircraft built. The A-7 Corsair has the distinction of being the only United States single seat jet fighter-bomber of the 1960s that was designed, built, and deployed directly into the Vietnam War. /A-7 Corsair II /
- In 1986,231 A-7Es were equipped to carry the Low-Altitude Night Attack (LANA) pod, which projected amplified light image on the HUD and, in conjunction with radar, provided terrain following down to 460 mph (740 km/h) at 200 ft (60 m). A total of 529 examples were modified (not counting 67 A-7Cs). The A-7E, 72 A-7D and A-7K aircraft were also modified to incorporate an improved FLIR pod with a new digital radar and Head Up Display. / A-7 Corsair II/
- The ANG A-7D/K Replacement Inertial Measurement System (RIMS) in late 1980s resulted in one of the first aircraft to employ a Ring Laser Gyro (RLG) and a more modern Tactical Mission Computer. Two prototypes of the supersonic YA-7F deep strike version was tested at Edwards AFB, before being canceled in 1990. / A-7 Corsair II /
A-7 Corsair II: Operational History…
- Initial operational basing/homeporting for U.S. Navy A-7 squadrons was at NAS Cecil Field, Florida for Atlantic Fleet units and NAS Lemoore, California for Pacific Fleet units. This was in keeping with the role of these bases in already hosting the A-4 Skyhawk attack squadrons that would eventually transition to the A-7. From 1967 – 1971 a total of 27 Navy squadrons took delivery of four different A-7A/B/C/E models. /A-7 Corsair II/
- The Vought plant in Dallas, TX employed up to 35,000 workers turned out one aircraft a day for several years to support the Navy carrier-based needs for Vietnam and SE Asia and commitments to NATO in Europe. In 1974, when the USS Midway (CV 41) became the first Forward Deployed Naval Force (FDNF) aircraft carrier to be homeported in Yokosuka, Japan, two A-7B squadrons assigned to Carrier Air Wing FIVE (CVW-5) were concurrently homeported at NAF Atsugi, Japan. In 1978, these squadrons (VA-93 and VA-56) finally transitioned to the much more advanced A-7E model. Six Naval Reserve squadrons would also eventually transition to the A-7, operating from NAS Cecil Field, Florida; NAS Atlanta/Dobbins ARB, Georgia; NAS New Orleans, Louisiana; NAS Alameda, California and NAS Point Mugu, California. An additional active duty squadron stood up in the 1980s, Tactical Electronic Warfare Squadron 34 (VAQ-34) at NAS Point Mugu, which would operate twin-seat TA-7C and EA-7L aircraft with both a pilot and a Naval Flight Officer in an adversary electronic warfare role. / A-7 Corsair II /
- Initial USAF basing of the A-7D was at Edwards AFB, California and Eglin AFB, Florida in 1968 for prototype testing. Initial lead-in pilot training squadrons were established at Luke AFB, Arizona, and Nellis AFB, Nevada in 1969. The first operational USAF basing was at Myrtle Beach AFB, South Carolina (354 TFW) in 1970, with subsequent basing at Davis-Monthan AFB, Arizona (355 TFW) in 1971 and England AFB, Louisiana (23 TFW) in 1972. The Luke-based A-7Ds were reassigned to Davis-Monthan in 1971 along with the lead-in pilot training mission. A fourth operational A-7D wing was assigned to Korat Royal Thai Air Force Base, Thailand (388 TFW) in early 1973 derived from deployed Myrtle Beach aircraft. / A-7 Corsair II /
- Pilots of the early A-7s lauded the aircraft for general ease of flying (with the exceptions of poor stability on cross-wind landings and miserable stopping performance on wet runways with an inoperative anti-skid braking system) and excellent forward visibility but noted a lack of engine thrust. This was addressed with A-7B and more thoroughly with A-7D/E. The turbofan engine provided a dramatic increase in fuel efficiency compared with earlier turbojets – the A-7D was said to have specific fuel consumption one sixth that of an F-100 Super Sabre at equivalent thrust. An A-7D carrying 12 x 500 lb (227 kg) bombs at 480 mph (775 km/h) at 33,000 ft (10,000 m) used only 3,350 lb (1,500 kg) of fuel per hour. Typical fuel consumption at mission retrograde during aircraft carrier recovery was approximately 30 pounds per minute compared to 100+ pounds per minute for the Phantom F-4J/N series. The A-7 Corsair II was tagged with the nickname “SLUF” (“Short Little Ugly Fucker”) by pilots. / A-7 Corsair II /
A-7 Corsair II: Use In F-117 Development…
- The 4450th Tactical Group stationed at Nellis AFB, Nevada had the distinction of being the last active USAF unit to operate the A-7 Corsair II. The mission of the 4450th TG was the operational development of the Lockheed F-117 Nighthawk, and the unit needed a surrogate aircraft for pilot training and practice. A-7Ds and A-7Ks were obtained from various active duty and air national guard squadrons and were assigned initially to the “(P)” or “Provisional” unit of the 4450th Tactical Group, redesignated the 4451st Tactical Squadron in January 1983.
- The A-7swere used as a deception and training aircraft by the group between 1981 and 1989. It was selected because it demanded about the correct amount of pilot workload expected in the F-117A, was single seat, and many of the F-117A pilots had F-4 or F-111 backgrounds. A-7s were used for pilot training before any F-117As had been delivered to bring all pilots to a common flight training base line. Later, the A-7s were used to chase F-117A tests and other weapon tests at the Nellis Range.
- A-7D-5-CV AF Serial No. 69-6241 of the 4451st Test Squadron / 4450th Tactical Group at Nellis AFB, Nevada in 1984. / A-7 Corsair II /
- A-7 flight operations began in June 1981 concurrent with the very first YF-117A flights. The A-7s wore a unique “LV” tailcode (for Las Vegas) and had a dark purple/black paint motif. The A-7s were based officially at Nellis Air Force Base and were maintained by the 4450th Maintenance Squadron.
- In addition to providing an excuse for the 4450th’s existence and activities, the A-7s were also used to maintain pilot currency, particularly in the early stages when very few production F-117As were available. The pilots learned to fly chase on F-117A test and training flights, perform practice covert deployments, and practice any other purpose that could not be accomplished using F-117As, given the tight restrictions imposed on all F-117A operations. / A-7 Corsair II /
- Some A-7s operated from the Tonopah Test Range Airport, about 30 miles (48 km) southeast of Tonopah, Nevada where the F-117s were being operationally tested. As a deception operation, care was taken to ensure that F-117As were never left parked outside aircraft hangars during daylight hours. However, A-7s were deliberately and routinely left outside hangars for the benefit of any orbiting Soviet spy satellites. Soviet intelligence agencies examining spy satellite imagery of the base would undoubtedly notice the A-7s parked on the Tonopah flight line, and would not be particularly interested. The intention of this deception was to convince the Soviets that Tonopah operated nothing more exciting than some A-7 Corsairs. / A-7 Corsair II /
- There were approximately 20 A-7D aircraft used in developing the F-117, including several two-seat A-7K trainers. In January 1989, just three months after the USAF admitted the F-117A existed, the A-7s were retired to AMARC and were replaced by AT-38B Talons as training aircraft and the 4451st TS was deactivated. / A-7 Corsair II /
A-7 Corsair II: Training And Retirement…
- Pilots quipped that the Corsair “is not very fast, but it sure is slow.” For dissimilar air combat training (DACT), and aerial demonstrations by the Blue Angels, the Navy would choose the more nimble Douglas A-4 Skyhawk as a subsonic maneuvering platform, as some considered the A-7 to be inadequate in air combat, even though it was highly maneuverable and was more fitting as a highly successful attack aircraft with a stable bombing platform. The Marine Corps would also pass on the Corsair, opting instead for the V/STOL vertical landing AV-8 Harrier as their light attack aircraft to replace their A-4F/M Skyhawks. / A-7 Corsair II /
- Naval Reserve and Air National Guard units, however, were often forced to operate the A-7E and D models in rather challenging air-to-air duels with USAF F-15 Eagles and USN Grumman F-14 Tomcats. Several A-7 units adopted a technique pioneered by the Puerto Rico Air National Guard: if an F-15 approaches gun range, depart the A-7 from controlled flight and deploy as much chaff and flares as possible. Departing an A-7 from controlled flight resulted in very high and simultaneous roll, yaw and pitch rates. It also caused a near instantaneous airspeed loss of 100 to 150 knots (190 to 280 km/h) that made successful gun-tracking by an opponent nearly impossible. Deploying chaff and flares during such an event spewed these devices in all directions as the range between the two aircraft rapidly diminished and consequently posed a chaff/flare collision threat to the attacking aircraft. / A-7 Corsair II /
- Beginning in 1974, active duty U.S. Air Force wings began transferring A-7Ds to Air National Guard (ANG) units. The Air Force had planned to end procurement of the A-7D in 1974 as a result of the development of the Fairchild-Republic A-10 Thunderbolt II, which was programmed to replace the Corsair as the Air Force’s close air support aircraft. However, Congressional decisions added additional funding to the DOD FY 1975 and FY 1976 budgets for the procurement of additional A-7Ds, primarily to keep the LTV production line in Dallas open and the workers employed in the wake of post-Vietnam DOD procurement reductions. As a result of these unplanned acquisitions, the Air Force assigned these new 1975 and 1976 built aircraft, along with new twin seat A-7Ks trainers in 1979 directly to the Air National Guard. In March 1976, A-10 production aircraft began arriving at active-duty units (355th TFW; 354th TFW) in 1977 and began replacing the Corsairs of active duty squadrons. The A-7Ds were subsequently transferred to Air National Guard units. / A-7 Corsair II /
- On 12 January 1981, in the 1981 Luis Muñoz Marín International Airport attack, 10 A-7Ds of the 198th Tactical Fighter Squadron, Puerto Rico Air National Guard were destroyed or damaged in a terrorist attack by the Boricua Popular Army at Muniz Air National Guard Base in the largest attack ever on American military station since the Vietnam War. This terrorist attack was largely unreported due to the Iran hostage crisis at the time.
- By 1981, with the exception of the A-7Ds used in the F-117A program, the last active-duty Corsairs were reassigned to ANG squadrons by the 23d Tactical Fighter Wing at England Air Force Base, Louisiana. Many active duty pilots missed the performance and sophistication of the Corsair. The A-7Ds used by the 4450th Tactical Group in Nevada were either retired or sent to ANG units in 1989. / A-7 Corsair II /
- F-16s began replacing the Air National Guard Corsairs beginning in the late 1980s and the last were retired in 1993 by the ANG units at Rickenbacker ANGB, Ohio; Des Moines International Airport/ANGB, Iowa; Tulsa International Airport/ANGB, Oklahoma; and Springfield-Beckley Municipal Airport/ANGB, Ohio.
- U.S. Navy A-7 Corsairs began being phased out of the fleet during the mid-1980s with the arrival of the McDonnell Douglas F/A-18 Hornet. The last Navy A-7s were retired by the last fleet operational squadrons (VA-46 and VA-72) in May 1991 shortly after their return from Operation Desert Storm. /A-7 Corsair II /
- Some of these surplus aircraft were passed to Greece, Thailand and Portugal; however by the end of 1998, with the exception of some airframes used as static displays, all US A-7s were disposed of by the AMARC at Davis-Monthan AFB, Arizona.
- The Hellenic Air Force ordered 60 new A-7H aircraft in 1974 and three TA-7Hs in 1980 and received 62 surplus A-7E/TA-7C from the USN after the Gulf War, 43 of which are still in use. The last squadron that uses the aircraft is the 336th. The A-7 was going to be replaced by a 4.5 generation fighter jet, but due to budget cuts, it will be retired in 2013, without a replacement.
- The Portuguese Air Force selected the A-7P (modified A-7A/B models) and flew them extensively from 1981 onward. The reliability and exceptional range allowing unrefueled routine flights to the Madeira Archipelago and Lajes AB in the Azores Archipelago.
- The sale of A-7s to Pakistan was not approved due to U.S. opposition to its nuclear program. /A-7 Corsair II /