Antonov An-22

Antonov An-22 Antei (Russian: Антей (Antaeus) (NATO reporting name "Cock") was the world's largest aircraft, until the advent of American C-5 Galaxy and later the Soviet An-124. Powered by 4 contra-rotating turboprops, the design remains the world's largest turboprop-powered aircraft. It first appeared outside the Soviet Union at the 1965 Paris Air Show.

Design features
The aircraft was design as a strategic airlifter, designed specifically to expand the capability of the airborne troops to land with their then-new BMD-1 armoured vehicles. The An-22 cargo hold can accommodate four of these as opposed to one in the An-12.

It also has the capability to takeoff from austere, unpaved and short airstrips, allowing airborne troops to perform air-landing operations. This is achieved by four pairs of contra-rotating propellers, similar to those on the Tupolev Tu-114. The engines generate significant thrust, and produce a slipstream over the wings and large double-slotted flaps. The landing gear is ruggedized for rough airstrips, and, in early versions, tire pressures could be adjusted in flight for optimum landing performance, although that feature was removed in later models.

The An-22 follows traditional cargo transport design with a high-mounted wing allowing a cavernous cargo space of 33m in length and a usable volume of 639m³. The forward fuselage is fully pressurized and provides space for 5 to 8 crew and up to 28passengers, but the cargo space is pressurized to only 3.55 PSI / 0.245 bar allowing for a lighter airframe. A door equipped pressure bulkhead is located at frame 14, separating the cargo attendant's compartment from the main cargo compartment. This allows the rear cargo doors to be opened during flight for paratroops and equipment drop. Like the An-12, the aircraft has a circular fuselage section. The An-22 has set a number of payload and payload-to-height world records[citation needed].

The An-22 has the general appearance of an enlarged version of the earlier Antonov An-12 except that it is fitted with a twin tail. This gives the An-22 better engine-out performance, and reduces height restrictions for hangars. Also of note are large anti-flutter masses on the top of each tail.

Only one production variant was built, the standard An-22. Prototypes, such as the one first featured at the 1965 Paris Air Show had fully-glazed noses that lacked the nose mounted radar of production models. Those aircraft had the radar mounted below the right wheel well fairing, forward of the wheels.

Specifications (An-22)

General characteristics

Crew: 5-6
Capacity: 29 passengers
Payload: 80,000 kg (180,000 lb)
Length: 57.9 m (190 ft 0 in)
Wingspan: 64.4 m (211 ft 3 in)
Height: 12.53 m (41 ft 1 in)
Wing area: 345 m² (3,713 ft²)
Empty weight: 114,000 kg (251,330 lb)
Max takeoff weight: 250,000 kg (551,000 lb)
Powerplant: 4× Kuznetsov NK-12MA turboprops driving contra-rotating propellers, 11,030 kW (15,000 shp) each

Performance

Maximum speed: 740 km/h (400 knots, 460 mph)
Range: 5,000 km (2,700 nm, 3,100 mi)
Service ceiling: 8,000 m (26,240 ft)