Mil Mi-6 "Hook"

Mil Mi-6 "Hook"

For more than ten years the Mi-6 has remained, dimensionally at least, the world's largest helicopter, and it was also the first turbine-powered helicopter to go into production in the Soviet Union. The first of five prototypes, flown by Rafail Kaprelian, made its maiden flight in autumn 1957, originally without the shoulder-mounted stub wings which are sometimes fitted to production Mi-6's. Considering the size of the machine, the flight development period of the Mi-6 was relatively short, and production is believed to have started early in 1960. During flight trials the Mi-6 established a number of impressive load-to-altitude and speed-with-payload records in 1959, most of which it bettered three years later when it set a total of eleven new FAI world records. In one of these, still unbeaten by early 1968, it lifted a payload of 20,117kg - greater than the entire weight of the biggest helicopter outside of the Soviet Union, the Sikorsky S-64A.

An initial batch of thirty production Mi-6's was undertaken, but this has undoubtedly now been exceeded, since the Mi-6 is known to be in both military and civil service inside the USSR and examples have also been supplied to the air forces of Algeria, Egypt, Ethiopia, Iraq, Syria, Vietnam and Peru. As a military transport the Mi-6 is capable of carrying up to 70 armed troops and has large rear clamshell loading doors for heavy loads such as army vehicles or large palleted items of freight. The Mi-6's in service with Aeroflot are employed mainly as freighters, in which role they have an internal capacity for 12000kg of payload. The standard passenger version seats 65 people normally, although up to 120 persons can be accommodated in a high density seating arrangement. If used as an ambulance, the Mi-6 can carry 41 stretchers and 2 medical attendants.

Despite the existence of the later Mi-10, the Mi-6 is still utilised in the flying crane role, when the stub wings (which provide some 20 per cent of the total lift) are usually omitted. The Mi-6 has already demonstrated publicly its ability to airlift such large items as the Vostok space capsule and would clearly be of equal use in large engineering projects, such as bridge-laying, the transport of oil drilling rigs, or even the transport of radio towers. The under-fuselage hook can support an externally slung load of 9000kg.

When first announced, following its maiden flight in September 1957, the Mil Mi-6 (NATO reporting name 'Hook') was by far the world's largest helicopter. Its maximum payload exceeds the total weight of the Sikorsky S-64A, which on its appearance a decade later was the largest helicopter outside the USSR. Developed to meet both VVS and Aeroflot requirements, the Mi-6 was also the first turbine-powered helicopter to enter production in the USSR. Five aircraft were involved in the development programme, which was completed very quickly for such a revolutionary aircraft, with production beginning in 1960. O.f conventional helicopter configuration, the Mi-6 introduced two readily-detachable short-span shoulder wings which offload the rotor by some 20 per cent in cruising flight; for heavy-lift operations the stub wings are removed to give greater payload capability. The Mi-6 was used in 1962 to set up no fewer than 14 speed and height-with-payload records that were ratified by the FAI; four of these remained unbeaten in 1983. Major production version was the Mi-6A of which more than 800 had been delivered when manufacture ended in 1981. The 'Hook' was exported to Algeria, Egypt, Ethiopia, Iraq, Syria, Vietnam and Peru, where it. is used by both the air force and army. Flown by a crew of five, the Mi-6 has also seen extensive use with Aeroflot in civil engineering support work on projects such as bridge-laying, and as a versatile heavy transport in areas inaccessible to other vehicles. Another version, developed into the Mil-10 'Harke', is optimized as a flying crane.

General characteristics

• Crew: 6 (pilot, copilot, navigator, flight engineer, radio operator, technician)
• Capacity: ** 90 passengers or
  • 70 airborne troops or
  • 41 stretcher cases with 2 medical personnel
• Payload: 12,000 kg (26,400 lb) of internal cargo
• Length: 33.18 m (108 ft 10 in)
• Rotor diameter: 35.00 m (114 ft 10 in)
• Height: 9.86 m (32 ft 4 in)
• Disc area: 962.1 m² (10,356 ft²)
• Empty weight: 27,240 kg (60,055 lb)
• Loaded weight: 40,500 kg (89,285 lb)
• Max. takeoff weight: 42,500 kg (93,700 lb)
• Powerplant: 2 × Soloviev D-25V turboshaft, 4,100 kW (5,500 shp) each
• Fuel load: 6,315 kg (13,922 lb)

Performance

• Maximum speed: 300 km/h (162 kt)
• Cruise speed: 250 km/h (135 kt)
• Range: 620 km (385 miles)
• Ferry range: 1,450 km(900 miles)
• Service ceiling: 4,500 m (14,750 ft)
• Disc loading: 44.17 kg/m² (9.05 lb/ft²)
• Power/mass: 0.21 kW/kg (0.13 hp/lb)

Mil Mi-4 "Hound"

Mil Mi-4 "Hound"

Design of the Mil Mi-4, a conventional helicopter with about four times the capacity of the Mi-1, was initiated in 1951 and the first example was flown during May 1952. Produced initially for use by the Soviet armed forces in assault and troop transport roles, the Mi-4 'Hound-A' has clamshell rear doors to simplify the loading of vehicles and freight; alternatively, the cabin can accommodate up to 14 troops. Military Mi-4s are recognisable easily by having a ventral gondola which was intended originally for a navigator or observer, but can also house avionics equipment. Produced in large numbers for Soviet military use, the Mi-4 was also exported for service with more than 20 foreign air arms. A number remain in current use, and in more recent years conversions have been reported in Soviet use for ASW ('Hound-B') armed close support and ECM ('Hound-C'). From 1964 production of civil versions was initiated and combined civil/military production by Mil was estimated at 3,500 when production terminated in 1969. All versions can be equipped with inflatable pontoons which, mounted so that the landing wheels project below them, can be used for amphibious operations. The Mi-4 was also manufactured under licence in China, a total of about 1,000 built when production ended in 1979, and of which approximately two-thirds were for civil use.

The Mi-4 was produced initially as a troop and assault transport helicopter for the Soviet armed forces. This version is characterised by circular cabin windows and a ventral fairing in which an observer can be stationed if required. Alternatively an additional fuel tank can be fitted in this position. One major difference between the Mi-4 and the S-55 is that the former has clamshell rear loading doors through which a maximum internal payload of 1600kg can be admitted. Typical military loads of the Mi-4 include 14 fully equipped troops, a GAZ-59 command vehicle, a 76mm anti-tank gun or 2 motorcycle combinations. Military Mi-4's have been exported to a number of air forces in the Soviet bloc, among the largest users being India, which has sixty, and Cuba, which has twenty-four.

From 1964 two civil versions of the Mi-4 were also built in considerable numbers. These were the Mi-4P (Passajirskii == passenger) and the Mi-4S (Selskokhoziaistvennii = rural economy). The Mi-4P is the standard version for Aeroflot, carrying 11 passengers normally or up to 16 in high density seating or, in the ambulance role, 8 stretchers and a medical attendant. The Mi-4P is distinguished by having square cabin windows, wheel spats and no ventral fairing; 100kg of baggage can be carried in addition to the normal passenger complement. The Mi-4S is normally used for agricultural operations, when it can be fitted with a 1000kg dust hopper or a 1600-l tank holding pesticide or fire-fighting chemical. All versions of the Mi-4 have provision for fitting inflatable pontoons in addition to the wheeled landing gear. A stripped-down Mi-4 established a number of speed-with-payload and payload-to-altitude records in 1956, and in more recent years both military and civil Mi-4's have performed a considerable amount of useful work in the Polar regions, their tasks including ice patrol and geological survey.

General characteristics

• Crew: One or two pilots
• Capacity: 16 troops or up to 1,600 kg (3,520 lb) of cargo
• Length: 16.80 m (55 ft 1.4 in)
• Rotor diameter: 21.00 m (68 ft 11 in)
• Height: 4.40 m (14 ft 5 in)
• Disc area: 346.4 m² (3,727 ft²)
• Empty weight: 5,100 kg (11,220 lb)
• Loaded weight: 7,150 kg (15,730 lb)
• Max. takeoff weight: 7,550 kg (16,610 lb)
• Powerplant: 1 × Shvetsov ASh-82V radial engine, 1,250 kW (1,675 hp)

Performance

• Maximum speed: 185 km/h (116 mph)
• Range: 500 km (313 mi)
• Service ceiling: 5,500 m (18,040 ft)
• Rate of climb: m/s (ft/min)
• Disc loading: 41 kg/m² (8 lb/ft²)
• Power/mass: 0.21 kW/kg (0.13 hp/lb)

Mil Mi-2 "Hoplite"

Mil Mi-2

The Mil Mi-2 (NATO reporting name Hoplite) is a small, lightly armored turbine-powered transport helicopter that could also provide close air support when armed with 57 mm rockets and a 23 mm cannon.Chronologically later than Mi-4 and Mi-6, Mi-2 was planned 1958-59 as modernized turbine derivative of Mi-1, just as Mi-8 was to Mi-4. Originally Mi-1 dynamic parts retained and mated with completely new fuselage, all light-alloy monocoque with steel forgings at concentrated loads, with twin turboshaft engines above cabin ahead of gearbox. Structural basis deep floor box carrying wheel or ski landing gears and housing flexible fuel cell of 600 lit. Normal accommodation for pilot and passenger (on right) with main cabin for 700kg cargo or seat unit for three passengers facing forward and three facing aft, with eighth passenger seat on right opposite rear door. Option of four stretchers and attendant, or slung load of 1.2t or two 600 lit ag containers. All versions plumbed for two 250-lit auxiliary tanks on sides.

First flight of V-2 Sept 1961. Subsequently developed as production Mi-2 with bonded/welded fuselage, hub with hydraulic instead of friction dampers, bleed-air anticed intakes, tail rotor with bonded-metal honeycomb blades and electro-thermal de-icing on all blades. Whole program transferred to WSK-Swidnik in Poland in Jan 1964. All production and development subsequently at WSK, involving 12 series versions including SAR, photo, anti-armour and gunship. Total by 1993 over 5320. ASCC name "Hoplite".

The Mi-2 was first introduced into the Soviet Air Force in 1965. The Mi-2 is used by mainly former Soviet and Eastern Bloc countries, although it was also purchased by Mexico and Myanmar armed forces. Most of the armed Mi-2 variants were used by Poland. Some were also used by the former East Germany (with machine gun and unguided rocket armament only).

North Korea still maintains a large active fleet of over 160 Mi-2s.

General characteristics

• Crew: One
• Capacity: 8 passengers or 700 kg (1,543 lb) internal, 800 kg (1,764 lb) external cargo
• Length: 11.40 m (37 ft 4¾ in)
• Rotor diameter: 14.50 m (47 ft 6⅞ in)
• Height: 3.75 m (12 ft 3½ in)
• Disc area: 165.13 m² (1,777.44 ft²)
• Empty weight: 2,372 kg (5,218 lb)
• Loaded weight: 3,550 kg (7,826 lb)
• Max. takeoff weight: 3,700 kg (8,157 lb)

Performance

• Maximum speed: 200 km/h (108 knots, 124 mph)
• Range: 440 km (237 nmi, 273 mi)(max internatal fuel, no reserves)
• Service ceiling: 4,000 m (13,125 ft)
• Rate of climb: 4.5 m/s (885 ft/min)
• Disc loading: 22.41 kg/m² (4.59 lb/ft²)

Mil Mi-1 "Hare"

Mil Mi-1

The Mil Mi-1 (USAF/DoD reporting name "Type 32", NATO reporting name "Hare") was a Soviet three- or four-seat light utility helicopter. It was the first Soviet helicopter to enter serial production. It is powered by one 575 hp Ivchenko AI-26V radial. It entered service in 1950 and was first seen on the 1951 Soviet Aviation Day, Tushino and was produced for 16 years. More than 1,000 were built in the USSR and 1,594 in Poland, as SM-1.  

Mikhail Mil began work on rotary-winged aircraft before 1930, but the Mi-1, his first production helicopter, was begun in 1946, under a designation EG-1. In 1947 Mil became a head of OKB-4 design bureau in Tushino, and works were intensified. A final design was named GM-1 (for Gelikopter Mila). Its design owed much to the Sikorsky S-51 and Bristol 171, with almost identical main rotor to the British machine and similar shafting and clutch. The prototype completed first free flight on 20 September 1948 (pilot Mikhail Baikalov). In 1949 it underwent official state trials. Despite crashes of two prototypes, the design was overally successful and after further work, was ordered for a production, under a new designation Mi-1, for Mil initials. The production was initially limited - the first series of only 15 machines was ordered on 21 February 1950, in factory No.3 in Moscow. 

Only after presentation to Joseph Stalin in 1951, the authorities decided to increase production. In 1952-1953, 30 Mi-1 were manufactured in Kazan, and from 1954 a mass production started in Orenburg and from 1956 in Rostov (current Rostvertol). The design was a subject of further improvements during production, mostly increasing reliability. Especially a rotor technology was changing. Period between repair increased to 300 hours in Mi-1T (hence a letter T for trekhsotchasovoi), 600 in Mi-1A, then to 1000 and 3000 hours by the end of production.

All early variants seated pilot in front and two passengers behind him, in common cabin. The first production variant was Mi-1, quickly replaced by improved Mi-1T, that carried extra operational equipment including full radio and blind-flying instruments, and had more reliable engine AI-26V. The next basic variant was Mi-1A of 1957, with further increased reliability and provisions for one 160 liter external fuel tank

.New major variant, Mi-1M of 1957, introduced enlarged cabin and slightly stronger engine AI-26VF, what allowed to accommodate three passengers on a bench behind the pilot. Cabin height increased from 1.22 to 1.26 m and width from 1.01 to 1.2 m. Most noticeable difference was horizontal bottom windows' line instead of slanted, with bigger rear side windows, and less pointed fuselage nose. It could also be fitted with two external side capsules for the injured or mail.There were trials of an armed anti-tank variant Mi-1MU carried in 1961, being the first Soviet attack helicopter, but it did not enter production due to small payload and cessation of production of a basic variant.

Mi-1M Note Side Capsules For Injured Troops

General characteristics

• Crew: One
• Capacity: 2 passengers or 255 kg (561 lb) of cargo
• Length: 12.09 m (39 ft 8 in)
• Rotor diameter: 14.35 m (47 ft 1 in)
• Height: 3.30 m (10 ft 10 in)
• Disc area: 161.7 m² (1,740 ft²)
• Empty weight: 1,700 kg (3,740 lb)
• Loaded weight: 2,140 kg (4,708 lb)
• Max. takeoff weight: 2,330 kg (5,126 lb)
• Powerplant: 1 × Ivchenko AI-26V radial engine, 429 kW (575 hp)

Performance

• Maximum speed: 185 km/h (115 mph)
• Range: 430 km (268 mi)
• Service ceiling: 3,500 m (11,480 ft)
• Rate of climb: 5.3 m/s (1,043 ft/min)
• Disc loading: 13 kg/m² (3 lb/ft²)
• Power/mass: 0.20 kW/kg (0.12 hp/lb)