<p>Affectionately known as the 'Warthog', the A-10 Thunderbolt II more than proved its worth as a 'tank-buster' in Operation Desert Storm when it single-handedly accounted for a large proportion of the Iraqi armor destroyed by coalition air power. Despite that success, the A-10 has never been exactly popular amongst the higher echelons of the USAF command structure and recent years have seen a decline in the number of active examples with various first and second-line elements of the Air Force.
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<p>The A-10 is uniquely dedicated to a single mission—killing tanks and other armoured vehicles. Its secondary role is CAS (close air support). In its anti-armor guise, the A-10 may be the only warplane of its era influenced by plans for Europe and Korea, rather than by combat in Vietnam. The armored threat posed by the Warsaw Pact (which has since been dismantled) and by North Korea (which still presents a threat) inspired the A-10. Regarded by some as too slow for a modern battlefield, the A-10 relies on maneuverability, armor and systems redundancy, rather than speed, to minimize vulnerability to ground fire.
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<p>In 1967, the USAF originated its A-X program for a new CAS warplane with anti-armor capability. The A-X was expected to be lethal against main battle tanks, tough and survivable, but still subsonic, in spite of an old fighter pilots' maxim that 'speed is life'.
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<p>Prototype awards were issued for the Northrop A-9A and Fairchild A-10A, the latter becoming the USAF's A-X choice on 18 January 1973. Counting six DT&E (development, test and evaluation) aircraft, the USAF made plans to acquire 733 A-10As.
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<p>First flight of the A-10A was made on 10 May 1972. The first production aircraft flew in February 1975. After developmental workups at Edwards AFB, California, and Eglin AFB, Florida, in 1976, Tactical Air Command (TAC) received its first A-10s for follow-on test and evaluation (FOT&E) at Davis-Monthan AFB, Arizona. The latter became the location of the first operational squadron, the 333rd Tactical Fighter Training Squadron, part of the 355th Tactical Fighter Training Wing, which equipped with the A-10 beginning in April 1976. Early developmental efforts were marred by the 3 June 1977 crash of an A-10 (75-0294) at the Paris air show.
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<p>The A-10—a compromise between weapons-carrying capability and affordable cost—was designed to use numerous major parts, including flaps, main landing gears and movable tail surfaces (interchangeable, left/right) and internal systems which were easy to maintain and redundant, thereby enabling the aircraft to survive if some parts were shot away. Locating the twin General Electric TF34-GE-100 turbofan engines (similar to those on the S-3 Viking ASW aircraft) atop the rear fuselage reduces infra-red signature and makes the A-10 relatively easy to fly on one engine. The A-10A's cannon is the most powerful (in muzzle velocity) ever installed on a tactical warplane, firing milk bottle-sized rounds at rates hydraulically controlled at 2,100 or 4,200 rounds per minute.
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<p>The 19 ft 10 in (6.06 m) long General Electric GAU-8/A cannon—a seven-barreled, rotating Gatling design, driven by the A-10's two hydraulic systems and fed with ammunition from a tub behind the cockpit—weighs only 620 lb (281 kg). A full load of API (armor piercing/incendiary) ammunition adds 2,066 lb (937 kg). The heaviest round employed by the cannon, API weighs 1.65 lb (0.75 kg) per round despite its aluminum casing. A 0.94-lb (0.43-kg) projectile leaves the barrel with a muzzle velocity of 3,240 ft (988 m) per second. The API round has a warhead of depleted uranium capable of penetrating any Soviet tank, including the T-80 series.
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<p>In addition to the cannon—which can disable a main battle tank from a distance of 21,600 ft (6,584 m)—the A-10A has proved potent against main battle tanks with the infra-red-imaging version of the AGM-65 Maverick missile.
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<p>The single-seat A-10A is intended to operate with as little support equipment as possible, from crude FOLs (forward operating locations) where facilities are sparse. Larger than most tactical attack aircraft, the A-10 uses a HUD (head-up display), Have Quick secure UHF (ultra-high frequency) radio, and both TACAN and inertial navigation to assist the busy pilot. Enhancing bombing accuracy of the aircraft is the Pave Penny laser guidance pod hanging from an off-center right pylon beneath the cockpit. This system requires laser illumination (normally from the ground) of the target, the pilot's attention being attracted by a HUD symbol on the illuminated target.
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<p>The A-10 'Warthog' is well-armored for protection of pilot and systems. Armor plate adds 2,900 lb (1,315 kg) to the aircraft's weight. The pilot is shielded by a bulletproof windscreen and encircled by a titanium armor 'bath tub' which weighs 1,200 lb (544 kg) and varies in thickness up to 1 in (3.8 cm). Coupled with the thick skin and innards of the aircraft, this armor is rated as adequate defense against a 23-mm cannon round.
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<p>Tests with a two-seat night/adverse-weather variant designated YA-10B (but usually called the N/AW A-10) did not lead to production of the A-10B variant, and the two-seat demonstrator airframe has long since been put to pasture. Production of the single-seat A-10A ended in 1983 with the 713th aircraft.
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<p>In the late 1980s the A-10 was selected for the fast FAC (forward air control) mission. This move was accomplished partly to generate a replacement for ageing OV-10 Broncos and OA-37B Dragonflys, but it also reflected the Air Force's internal difficulty with the A-10: the service had long wanted a version of the F-16 Fighting Falcon for CAS/BAI (close air support/battlefield area interdiction) and welcomed a chance to shunt the A-10 to other duties. Externally unmodified, the fast FAC OA-10 came into existence and now operates with several units.
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<p>The A-10 was designed for a European or Korean scenario. At the height of its career, more than 100 served with the 81st Tactical Fighter Wing at RAF Bentwaters-Woodbridge, UK, forming no fewer than six squadrons, which frequently deployed to five FOLs in West Germany. In 1988, two of the 81st's squadrons were transferred to the 10th TFW at RAF Alconbury, UK. This unit participated in Desert Storm before being deactivated in 1992. A-10s remain at Osan AB, RoK, where armored threat to US forces persists in the post-Cold War era. OA-10s also serve at Eielson AFB, Alaska.
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<p>The rugged A-10 had been designed to support US Army ground troops in daylight. But in the 1980s, US forces gradually shifted to the concept of an AirLand battle—or 'joint' battle employing close co-operation between the services—in which much of the fighting would be conducted at night, to exploit US technology. The simple and straightforward A-10, which had been built without a terrain-avoidance radar (and rejected by the USAF in its night/adverse-weather version) now seemed out of date. Still, the A-10 rehearsed night desert warfare at the NTC (National Training Center), Fort Irwin, California. At NTC, pilots flew in dust and haze against tanks in very realistic practice fighting.
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<p>Plans were well advanced to phase out the A-10 when the warplane was granted a reprieve for Operation Desert Shield, the Middle East buildup which followed Iraq's invasion of Kuwait on 2 August 1990. Typical of deployments made during Desert Shield was that of the 23rd Tactical Fighter Wing, England AFB, Louisiana, whose pilots made a 13.1-hour overnight flight to Spain, refueled immediately, and flew another 10 hours to King Fahd Airport, Saudi Arabia, with eight air-to-air refuelings.
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<p>The A-10 force deployed to the Saudi desert included the 23rd TFW; the 354th TFW from Myrtle Beach AFB, South Carolina; and one squadron (511th TFS) from the 10th TFW at Alconbury, UK. In addition, the Air Force Reserve's 706th TFS from New Orleans, Louisiana, and the 23rd TASS with OA-10As from Davis-Monthan AFB, Arizona, participated in the buildup and the conflict.
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<p>The USAF deployed 144 A-10s to the war zone. During the January-February 1991 fighting, when air superiority was quickly gained, A-10s were used in innovative fashion in various roles. A daytime tank killer, the A-10 also became a daytime 'Scud' hunter in Western Iraq, suppressed enemy air defenses, attacked early warning radars, and even shot down two helicopters with its cannon—the only air-to-air victories accomplished with guns during the conflict. While the A-10 flew almost 8,100 combat sorties, it maintained a mission-capable rate of 95.7 per cent.
