Mil Mi-8 "Hip"

Mil Mi-8 "Hip"

The Mi-8, appeared in prototype form towards the end of 1961. In broad terms it bears the same relationship to the Mi-4 as the Mi-2 has to the Mi-1, and (initially at least) the rotor hub, rotor blades, rear fuselage boom and certain undercarriage components were similar to those employed in the Mi-4. The original prototype was powered by a single 2700shp Soloviev shaft turbine mounted over the cabin roof, but in the second machine, which flew for the first time on 17 September 1962, this was replaced by two of the smaller Isotov engines of 1500shp each. The latter has been the standard installation on all subsequent aircraft, the only major design change being the substitution of a 5-blade rotor for the original 4-blade one in 1964.

Intended primarily for Aeroflot, the Mi-8 carries a 2- or 3-man crew and has seating accommodation for up to 28 passengers in its standard airline form. Alternative internal arrangements include a de luxe saloon cabin for executive travel or a cargo layout for an internal payload of 4000kg. Emergency conversion of the cargo model to a passenger carrier can be carried out quickly by installing 24 tip-up seats along the cabin sides. Clamshell rear doors are provided for loading large items of cargo or, in the ambulance role, 12 stretchers which can be carried with an accompanying medical attendant. Like the other Mil turbine helicopters, the Mi-8 can also be used as a rescue machine with a winch on the cabin side capable of lifting a 250 kg load, or with an under-fuselage hook for an external sling load of about 2500 kg.

Designed originally in 1960, the V-8 'Hip-A' prototype helicopter was basically a turbine-powered version of the Mi-4, retaining initially its rotor, transmission and a number of other components. Intended powerplant was two Isotov turboshaft engines, but as these were not fully developed when the V-8 was nearing completion, it was powered instead by a single large Soloviev turboshaft derated to the 2013kW limit of the transmission, for its first flight in June 1960. However, the second machine (flown for the first time on 17 September 1962) introduced the Isotov engines, each then rated at 1119kW, and this became the standard installation on early production aircraft, designated Mil Mi-8 (NATO reporting name 'Hip'). The only other major change to be introduced since that time resulted from problems with the main rotor inherited from the Mi-4, replaced in 1964 by a five-bladed rotor of more advanced design in the 'Hip-B' prototype. The availability of so much engine power, by comparison with the 1268kW of the Mi-4, meant the new helicopter had a larger cabin, providing accommodation for a crew of two or three and up to 28 passengers in a standard airline configuration. Since series construction began, a total of 10,000 Mi-8s have been built, for both civil and military use. Some components are built in China. Large numbers of Mi-8s are used by Aeroflot in the transport role, being deployed also for ice reconnaissance, rescue operations and logistic support, but even greater numbers are operated by the Soviet Union's Frontal and Naval Aviation and, in addition, these helicopters have been supplied to the armed forces of about 40 other nations. The military versions are identified usually by their NATO reporting names.

General characteristics

• Crew: 3 (pilot, copilot, flight engineer)
• Capacity:
  
  • 24 passengers or
  • 12 stretchers and seat for 1 medical attendant or
  • 3,000 kg (6,600 lb) on internal/external hardpoints
• Length: 18.17 m (59 ft 7 in)
• Rotor diameter: 21.29 m (69 ft 10 in)
• Height: 5.65 m (18 ft 6 in)
• Disc area: 356 m² (3,832 ft²)
• Empty weight: 7,260 kg (16,007 lb)
• Loaded weight: 11,100 kg (24,470 lb)
• Max. takeoff weight: 12,000 kg (26,455 lb)
• Powerplant: 2 × Klimov TV3-117Mt turboshafts, 1,454 kW (1,950 shp) each
• Fuel max total capacity: 3,700 l (977 US gal)

Performance

• Maximum speed: 260 km/h (140 kt)
• Range: 450 km (280 mi)
• Ferry range: 960 km(596 mi)
• Service ceiling: 4,500 m (14,765 ft)

Armament

• up to 1,500 kg (3,300 lb) of disposable stores on six hardpoints, including 57 mm S-5 rockets, bombs, or 9M17 Phalanga ATGMs.