| An-22 "Antei" | |
|---|---|
 | |
| Antonov An-22 | |
| Role | Strategic airlifter |
| Manufacturer | Antonov |
| Designed by | Oleg Antonov |
| First flight | 27 February 1965 |
| Introduced | 1967 |
| Status | Some remain in active service |
| Primary users | Soviet Air Force Aeroflot Antonov Airlines |
| Produced | 1965-1975 |
| Number built | 68 |
The Antonov An-22 Antei (Ukrainian and Russian: Антей (Antaeus) (NATO reporting name "Cock") was the world's largest aircraft, until the advent of the American C-5 Galaxy and later the Soviet An-124. Powered by four 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 and development
In the late 1950s the Soviet Union had a requirement for a large military transport aircraft to supplement the Antonov An-8 and An-12s then entering service.Originally known as the An-20 it was a conventional multi-engined high-wing design. In the early 1960s the company produced a wooden mock up at the company workshops at Kiev of what was designated the Model 100. The prototype now designated the An-22 was rolled out 18 August 1964 and first flew on 27 February 1965. The prototype was given the name Antheus and after four-months of test flying was displayed at the 1965 Paris Air Show. Production aircraft were built at the State Aircraft Factory in Tashkent and the first delivery was made to the Air Transport Wing at Ivanova Airbase in 1969.
The aircraft was designed 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 28 passengers, 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.
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. Antonov designated a variant with a modified electrical system and an additional augmented flight control system the An-22A but the designation was not used by the military.
Operational history
The An-22 was originally built for the Soviet Air Force and Aeroflot, the state airline. The conversion from An-12 in the Air Force began in July 1974. The 12th Mginsk Red Banner air transport aviation division (airbase Migalovo) was one of the units which had its three regiments entirely equipped with the An-22s. Another unit that operated it was the 566th 'Solnechnogorsk' Military Transport Aviation Regiment, which used the An-22 from 1970 to 1987.
The An-22s from Migalovo were used for the initial insertion of the VDV troops in to Kabul, Kandahar and Bagram during the 1979 Soviet war in Afghanistan. One An-22 was shot down near Kabul in 1984, killing 240 people. In 1980 one An-22 crashed at Vnukovo International Airport while two more crashed at Migalovo in 1992 and 1994.
In 1984 the military aircraft were used to deliver Mi-8 helicopters to Ethiopia during drought relief operations.
In 1986 the aircraft of the 8th air transport aviation regiment from Migalovo were used to deliver materials for the containment of the Chernobyl disaster effects.
During 1987 the aircraft were used to deliver military equipment to Angola. A year later the military An-22s were used to deliver 15,000 tons and 1,000 personnel in aid of the relief of earthquake disaster in Armenia.
The An-22 aircraft were often seen at the Le Bourget Air Show, and in 1988 delivered an engine from An-124 to the Farnborough Airshow.
An-22s were used to deliver internal security troops to many ethnic regional conflicts during and after the break up of the Soviet Union, and during the withdrawal of Soviet troops from Germany, notably airlifting the 104th Guards Airborne Division. In 1995 they delivered the Russian peacekeeping contingent from the 98th airborne division to Bosnia - Herzegovina during the Bosnian War.
Approximately 45 remained in service by the mid-1990s, mostly with the Russian Air Force, but these are slowly being replaced by the bigger turbofan-powered Antonov An-124. The remaining An-22s appear to be operated by an independent military transport aviation squadron at Tver (Migalovo). Currently one An-22 is in use for civilian cargo duties with Antonov Airlines.
A proposed civil airliner version capable of seating 724 passengers on upper and lower decks was not built. (For comparison, a typical Boeing 747 can carry 400-500 passengers.)
As of 2004 there had been 8 accidents with a total of 83 fatalities.
The aircraft is also used in special operations.
Variants
An-22
Prototypes built at Kiev-Svyatoshino with glass nose, three built.
An-22
Initial production variant with external start system, 37 built at Tashkent.
An-22A
Improved variant with air-start capability, modified electrical system, and updated radio and navigation equipment, 28 built at Tashkent.
Operators
Military
Former
Soviet Union
Soviet Air Force.
Current
Russia
Russian Air Force.
Civil
The Antonov design bureau retained the three prototype aircraft for use as special cargo transports. Two aircraft were modified to carry An-124 wings above the fuselage.
In August 2006 a single Antonov An-22 aircraft remains in airline service with Antonov Airlines.
Operators included:
Bulgaria
Air Sofia (leased)
Ukraine
Antonov Airlines
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)
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