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Russia’s most unique Mil helicopters

As the renowned Mil Helicopter Design Bureau marks 70 years since it was established, TASS tells about the legendary company’s most unusual and interesting projects

The Helicopter Experimental Design Bureau led by aircraft designer Mikhail Mil was established in Moscow on December 12, 1947.

Over its entire history, the Mil Design Bureau has designed 13 baseline helicopter models, from the light to the super-heavy classes, including the world’s most popular Mi-8 rotorcraft. 

Mi-1 helicopter Alexei Stuzhin/TASS
Mi-1 helicopter
© Alexei Stuzhin/TASS

Today the Mil Moscow Helicopter Enterprise (part of Russian Helicopters Group) is one of the world’s most renowned helicopter developers whose rotorcraft are operational in more than 100 countries and are the mainstay of the helicopter fleet in Russia and some countries of the CIS, Asia, Africa, the Middle East and Latin America.

According to the data of Russia’s state arms seller Rosoboronexport, post-Soviet states continue operating a considerable number of Mi-8, Mi-24 and Mi-26 helicopters. These helicopters are especially popular due to their low cost and the availability of trained flight and technical personnel.

Mi-1, the first serial-produced helicopter

The first Soviet serial-produced rotorcraft was initially called the Mil helicopter-1. It performed its debut flight in 1948 and went into service in 1951 while its serial production began three years later.

The Mi-1 was equipped with a 575 hp engine and could fly at a speed of up to 170 km/h at an altitude of no more than three km. Two passengers could also stay in the chopper’s cabin, apart from the pilot. The helicopter’s design was based on the classical single-rotor configuration with the three-blade main and tail rotors. For many decades, Mi-1 helicopters were actively used both in civil aviation and in the country’s armed forces. Mi-1 rotorcraft were involved in the delivery of both mail and cargoes, the evacuation of ill and injured persons from hard-to-access areas and were also used for the treatment of agricultural land.

Overall, about a dozen of the helicopter’s modifications were developed for various conditions of its operation. The helicopter’s production came to a halt in 1960. Overall, more than 2,600 such rotorcraft had been built.

Most of the helicopters that were produced in Poland were purchased by the Soviet Union. Poland developed two modifications of this helicopter, the SM-1 and the SM-2.

Interestingly, the Mi-1T, an upgraded version of the Mi-1, was tested in 1957 as a military communications laying rotorcraft. The helicopter’s boards were furnished with telephone wire coils, which helped the rotorcraft lay a 13 km communications line per flight.

Mi-8, the most mass-produced helicopter

The Mi-8 is one of the most mass-produced helicopters in history. Over 5,000 helicopters of the Mi-8/17 family have been registered in 92 countries. More than 1,500 Mi-8 helicopters have been delivered to foreign customers since 1991.

Mi-8 military helicopters  Sergei Bobylev/TASS
Mi-8 military helicopters
© Sergei Bobylev/TASS

People nicknamed the Mi-8 “Kolya” or “Mykolka” (the Ukrainian version of the diminutive name of Kolya).

The helicopter performed its debut flight on June 24, 1961. It has been in operation since 1965. A total of over 12,000 Mi-8 helicopters have been produced. The rotorcraft is powered by two 2,000 hp engines allowing it to develop a speed of up to 270 km/h. The early versions of the Mi-8 helicopter have been in service since the war in Vietnam and have proven their worth in all local conflicts over the past 40 years.

Overall, more than 130 Mi-8 modifications have been developed, including heavily upgraded versions – the Mi-8MT, the Mi-17 and the Mi-171 – for civil and military operators.

The Mi-17-1V is the most popular model. Moreover, up to 90% of these helicopters are exported. This model can be delivered with different equipment sets. The Mi-171Sh is a popular model for Russia and CIS countries. Since 2016, the Russian troops have been receiving the Mi-8AMTSh-VA, a new modification of the Mi-8 helicopter, for operation in the Arctic.

A report by Flight International analytical center focused on the prospects of the development of the Air Force in different countries indicates that there were 2,555 helicopters of the Mi-8/17 family in the world as of late 2015, making up 13% of the world’s entire helicopter fleet.

Mi-10K, the ‘flying crane’

This is the civil version of the Mi-10 military and transport helicopter optimized for carrying out construction and assembly works and nicknamed ‘the flying crane.’ This is a version with “short legs” and an additional pilot’s cabin under the fuselage.

The helicopter performed its debut flight in June 1965 and its production began in 1975. Overall, 17 such helicopters were produced and four others were re-equipped from the baseline Mi-10 rotorcraft. The designers fully gave up hydraulic claws and the external platform and reduced the running gear height, which lowered the rotorcraft’s weight and its drag.

Instead of TV cameras that failed to be effective in controlling the helicopter during loading and unloading operations, the Mi-10K was furnished with an additional suspended pilot’s cabin with a panoramic view and a third set of control levers.

The experimental Mi-10 set a record on September 23, 1961, lifting 15,103 kg of cargo to an altitude of 2,200 m. The serial production of Mi-10 rotorcraft, which began in 1964, equaled only 24 helicopters. They failed to find a broad use as the hydraulic claws’ grab required equipping the cargoes with reciprocal clutches.

Mi-12, the most powerful helicopter by its cargo lifting capacity

It is the heaviest and the most powerful helicopter by its cargo lifting capacity in the entire history of world aviation. It performed its debut flight on July 10, 1968 and on August 6, 1969 it set a world record for helicopters unbeaten up to date by lifting a cargo of 44,205 kg to an altitude of 2,255 m. Overall, Mi-12s have set seven world records.

For its development of the super-heavy helicopter, the Mil Design Bureau was awarded the Sikorsky Prize conferred by the American Helicopter Society for outstanding achievements in rotorcraft engineering.

As its specific feature, the Mi-12’s rotors are mounted at the far edges of the inverse tapered wings. The rotorcraft was developed as a super-heavy helicopter with a lifting capacity of no less than 30 tonnes to transport intercontinental ballistic missiles for units of the country’s Strategic Missile Force. The 105-tonne super-heavy chopper was powered by four 6,500 hp engines. The Mi-12 could develop a speed of up to 260 km/h and had a crew of six men.

The helicopter’s front fuselage accommodated a two-deck cabin. Its tail housed a drop-down cargo ramp with side flaps, which formed an aperture when opened for loading cargo and hardware. A huge cargo hold occupied the helicopter’s central part. However, the troops had no need for such a giant rotorcraft and both helicopters were turned into museum exhibits. However, the experience of designing and testing these exceptional helicopters came in handy afterwards.

Mi-14 amphibious helicopter

This is the sole domestic shore-based amphibious helicopter. Its serial production was organized in late 1973. A total of 273 such helicopters were produced in 1973-1986. This rotorcraft was extremely necessary for the Soviet Navy as an anti-submarine helicopter. But it was also widely used for peaceful purposes to transport passengers and cargo, carry out search and rescue operations and fight forest fires. A derivative of the Mi-8 rotorcraft, it had the following basic modifications: the antisubmarine warfare helicopter (the Mi-14PL), the rescue helicopter (the Mi-14PS) and the helicopter trawler (the Mi-14BT).

The primary difference in the Mi-14’s design compared to the Mi-8 is the sealed boat bottom installed instead of the reinforced floor, which allows the helicopter to land on the water with a sea disturbance of up to 3-4 points. The Mi-14 was also furnished with additional fuel tanks, which allowed it to perform long air patrols. The Mi-14 became the first Soviet helicopter with retractable running gear.

Today Mi-14 helicopters have been removed from operation in the Russian Navy but are used in civil aviation and by the Emergencies Ministry on a limited scale, and are also in service in Poland where they have been upgraded. Another four Mi-14 helicopters are operational in Ukraine and at least one is in service in Georgia.

At the St. Petersburg International Maritime Defense Show on July 2, 2015, Russian Helicopters Group (part of state hi-tech corporation Rostec) presented the project of resuming the production of Mi-14s. The helicopter is expected to be heavily upgraded and used both in the military and civil spheres.

The Mi-14 has a whole range of unique features, including its lifting capacity and the ability to land on the water surface, Russia’s Deputy Defense Minister Yuri Borisov said in 2015 during his visit to the Kazan Helicopter Enterprise.

As the deputy defense minister said, the Mi-14 had not been produced over the past 20 years and, therefore, it was now necessary to resume the production of the helicopter’s new modification that would meet modern requirements.

Mi-24, the flying IFV

The world’s most frequently used helicopter in combat. It participated in over 30 local conflicts: in combat operations in the Pamir Mountains, in Caucasian gorges, in tropical forests of equatorial Africa and in scorching Asian deserts. This is the first Soviet combat helicopter. It gained military glory in Afghanistan where it was nicknamed the ‘Crocodile.’

The Mi-24 is the sole attack helicopter capable of performing troop landing functions and nicknamed the flying infantry fighting vehicle (IFV). It is designed to provide fire support for troops on the battlefield and carry out tactical airborne force landings. It can also perform transport functions. The helicopter made its debut flight on September 19, 1969. The Mi-24 was serial-produced from 1970 to 1989. A total of about 3,500 Mi-24s were manufactured. In 1978, the Mi-24 set an absolute world record for helicopters, developing a speed of 368.4 km/h.

Mi-24 helicopters are currently operational in the armies of about 45 countries. Overall, foreign customers received 171 Mi-24 assault gunships in 1991-2014.

The Mi-24 became a symbol of the transport and attack helicopter. The Mi-24Ps with the canon armament were the most popular models from 1991. There were also deliveries of the Mi-24V helicopter armed with a quad-barreled 12.7mm machine-gun. Today the troops are receiving the Mi-35, an upgraded version of the Mi-24 helicopter.

Mi-26, the ‘flying cow

The world’s most powerful serial-produced helicopter by its weight-lift capacity nicknamed the ‘flying cow’ for its dimensions. The Mi-26 is designed to accomplish transport, evacuation, firefighting and other missions. The helicopter performed its debut flight on December 14, 1977. It has been serial-produced since 1980 and a total of over 300 such helicopters have been manufactured.

It is equipped with a single eight-blade main rotor and a five-blade tail rotor, two turboshaft engines and fixed tricycle landing gear. Depending on the helicopter’s modification, the crew can comprise five-six members. The Mi-26 can develop a maximum speed of 270 km/h and has a maximum flight range of 800 km with main fuel tanks and a service ceiling of 4,600 meters. The helicopter is capable of carrying up to 85 paratroopers on its board or 60 injured persons on stretches or up to 20 tonnes of cargo inside it or from an external sling.

About 15 modifications have been derived from the Mi-26 helicopter. In 2015, Russian Helicopters rotorcraft manufacturer launched the serial production of the Mi-26T2, an upgraded version of the Mi-26. It is furnished with new avionics, which makes it possible to cut the crew from five to two or three men and use the helicopter at night. Besides, it does not require special aerodrome maintenance means and is suited for long-term autonomous basing. The helicopter set a record in 1996, lifting 224 parachuters to an altitude of 6,500 meters.

In 2009, the Mi-26T transported a 27-meter Alinghi 5 catamaran and then a Tu-134 passenger plane. No other helicopter performed such operations in the entire history of rotorcraft engineering. It is worthy to note that Mi-26 helicopters performed 50 long-distance missions in the Arctic in 2017, delivering about 600 tonnes of cargo.

Perspective High-Speed Helicopter (PSV)

The PSV flying laboratory is an experimental rotorcraft based on the Mi-24 model. It is furnished with the main rotor’s new all-composite blades. Some fuselage elements of the flying laboratory have been further developed to reduce air drag and improve the helicopter’s aerodynamics at high speeds. The perspective helicopter is expected to go into serial production from 2022 and will be able to develop a speed of up to 500 km/h.

The helicopter took to the skies for the first time in late December 2015 at the flight testing center of Moscow’s Mil Helicopter Enterprise. The PSV project aims to develop technological potential for increasing the speed of helicopters by 1.5 times compared to serial-produced rotorcraft manufactured today.

 The new perspective helicopter has developed a speed of over 400 km/h for the first time, using the classical scheme with one main rotor. Foreign manufacturers have also achieved similar speeds but only with the use of the rotor scheme based on the propulsion force.

 

 Roman Azanov

TASS would like to express its gratitude to the press office of Russian Helicopters Group for assistance in preparing this material