TITLE:

FAIRCHILD REPUBLIC 'Thunderbolt II'

USAF designation: A-10A/OA-10

TYPE:

Single-seat close support aircraft.

PROGRAMME:

Fairchild Republic and Northrop each built two prototypes for evaluation under the US Air Force's A-X programme, initiated in 1967, for a close support aircraft. The first Fairchild Republic prototype (71-1369), designated YA-10A, flew for the first time 10 May 1972. It was announced 18 January 1973 that Fairchild was the winner of the competitive evaluation of the prototypes, and received a contract for six A-10A DT and E aircraft, the first of which flew 15 February 1975.

The first flight by a production A-10A Thunderbolt II (75-00258) was made 21 October 1975. Purchase of a total of 739 aircraft was planned (including the six DT and E aircraft); but funding was terminated in 1983 after a total of 713 production A-10s had been ordered. Delivery was completed 20 March 1984. There were still 327 aircraft in service with the USAF, USAF Reserve and ANG in early 1994. The Thunderbolt II was used during the Gulf War of 1991.

Export versions of the A-10 were available as single-seat night attack and two-seat combat-ready trainer aircraft. Night capability is provided by the addition of a Westinghouse WX-50 radar, Texas

Instruments AAR-42 FLIR, Litton LN-39 inertial navigation system, Honeywell APN-194 radar altimeter, AiResearch digital air data computer, Ferranti 105 laser rangefinder and Kaiser head-up display.

It is expected that night/adverse weather capability can be improved with the addition of a LANTIRN (low-altitude navigation targeting infrared for night) fire control pod.

The first combat-ready A-10A wing was the 345th Tactical Fighter Wing, based at Myrtle Beach, South Carolina, to which deliveries began in March 1977.

DESIGN FEATURES:

Cantilever low-wing monoplane, with wide chord, deep aerofoil section (NACA 6716 on centre-section and at start of outer panel, NACA 6713 at tip) to provide low wing loading. Incidence -1 degrees. Dihedral 7 degrees on outer panels.

FLYING CONTROLS:

Wide span ailerons made up of dual upper and lower surfaces that separate to serve as airbrakes. Flaps, airbrakes and ailerons actuated hydraulically. Ailerons pilot-controlled by servo tab during manual reversion. Small leading-edge slat inboard of each mainwheel fairing. Redundant and armour-protected flight control system. Interchangeable elevators, each with an electrically operated trim tab. Rudders and elevators actuated hydraulically.

STRUCTURE:

Aluminium alloy three-spar structure, consisting of one-piece constant-chord centre-section and tapered outer panels with integrally stiffened skins and drooped (cambered) wingtips. Outer panel leading-edges and core of trailing-edges are of honeycomb sandwich.

LANDING GEAR:

Menasco retractable tricycle type with single wheel on each unit. All units retract forward, and have provision for emergency gravity extension. Interchangeable mainwheel units retract into non-structural pod fairings attached to the lower surface of the wings.

POWER PLANT:

Two General Electric TF34-GE-100 high bypass ratio turbofan engines, each rated at 40.3 kN (9065 lb st), enclosed in separate pods, each pylon-mounted to the upper rear fuselage at a point approximately midway between the wing trailing-edges and the tailplane leading-edges. Fuel is contained in two tear-resistant and self-sealing cells in the fuselage, and two smaller, adjacent integral cells in the wing centre-section. Maximum internal fuel capacity 4853 kg (10,700 lb).

ACCOMMODATION:

Single-seat enclosed cockpit, well forward of wings, with large transparent bubble canopy to provide all-round vision. Bulletproof windscreen. Canopy is hinged at rear and opens upward. Douglas ejection seat operable at speeds of 450 knots (834 km/h; 518 mph) down to zero speed at zero height. Entire cockpit structure is protected by an armoured 'bathtub' structure of titanium, capable of withstanding projectiles up to 23 mm calibre.

ARMAMENT:

General Electric GAU-8/A Avenger 30 mm seven-barrel cannon, mounted in nose with 2 degrees depression and offset slightly to port so that as the barrels rotate the firing barrel is always on the aircraft's centreline. Gun and handling system for the linkless ammunitions are mechanically synchronised and driven by two motors fed from the aircraft's hydraulic system. The single drum magazine has a capacity of 1350 rounds, and has a dual firing rate of either 2100 or 4200 rds/min. Four stores pylons under each wing (one inboard and three outboard of each mainwheel fairing), and three under fuselage, for max external load of 7.257 kg (16,000 lb). External load with full internal fuel is 5482 kg (12,086 lb). The centreline pylon and the two flanking fuselage pylons cannot be occupied simultaneously. The centreline pylon has a capacity of 2268 kg (5000 lb); the two fuselage outer pylons and two centre-section underwing pylons 1587 kg (3500 lb) each; the two innermost outerwing pylons 1134 kg (2500 lb) each; and the four outermost wing pylons 453 kg (1000 lb) each. These allow carriage of a wide range of stores, including 28 226 kg (500 lb) Mk 82 LDGP general purpose bombs; eight BLU-1 or BLU-27/B Rockeye II cluster bombs, 16 CBU-52/71, 10 AGM-65A Maverick missiles; Mk 82 and Mk 84 laser-guided bombs; Mk 84 electro-optically guided bombs; two SUU-23 pods; chaff or other jammer pods; or up to three drop tanks.

DIMENSIONS: EXTERNAL:

Wingspan: 17.53 m (57 ft 6 in)

Wing chord:

at root: 3.04 m (9 ft 11 1/2 in)

mean: 2.73 m (8 ft 11 1/3 in)

at tip: 1.99 m (6 ft 6 2/5 in)

Wing aspect ratio: 6.54

Length overall: 16.26 m (53 ft 4 in)

Height overall: 4.47 m (14 ft 8 in)

Tailplane span: 5.74 m (18 ft 10 in)

WEIGHTS AND LOADINGS:

Manufacturer's empty weight: 9183 kg (20,246 lb)

Basic equipped weight,'clean': 10,600 kg (23,370 lb)

Operating weight empty: 10,710 kg (23,611 lb)

Basic design weight, equipped:13925 kg (30,700 lb)

Max T.O. weight: 500 kg (47,400 lb)

Thrust/weight ratio 0.6

PERFORMANCE (at max T.O. weight except where indicated):

Never exceed speed: 450 knots (834 km/h; 518 mph)

Max combat speed at S/L, 'clean': 390 knots (722 km/h; 449 mph)

Combat speed at 1525 m (5000 ft)

with six Mk 82 bombs: 385 knots (713 km/h; 443 mph)

Cruising speed at S/L: 300 knots (555 km/h; 345 mph)

Cruising speed at 1525

(5000 ft): 342 knots (634 km/h; 394 mph)

Stabilised 45 degrees dive speed below 2440 m (8000 ft), AUW of

15,932 kg (35,125 lb): 260 knots (481 km/h; 299 mph)

Max rate of climb at S/L at

basic design weight: 1828 m (6000 ft)/min

T.O. distance:

at max T.O. weight: 1372 m (4500 ft)

at forward airstrip weight: 426 m (1400 ft)

Landing distance:

at max T.O. weight: 762 m (2500 ft)

at forward airstrip weight: 382 m (1250 ft)

Operational radius:

close air support and escort, 2 h loiter,

20 min reserves: 250 nm (463 km; 288 miles)

reconmissance: 400 nm (740 km; 460 miles)

deep strike: 540 nm (1000 km; 620 miles)

LENGTH (m): 16.26

HEIGHT (m): 4.47

WINGSPAN (m): 17.53

MAX T.O. WEIGHT (kg): 21,500

MAX WING LOAD (kg/m/2): 449.88

T.O. RUN (m): 1372

LANDING RUN (m): 762

MAX RATE CLIMB (m/min): 1828