The Mil Mi-26 (Russian: Миль Ми-26, NATO reporting name: Halo), given the product code izdeliye 90, is a Soviet/Russian heavy transport helicopter. In service with civilian and military operators, it is the largest and most powerful helicopter ever to have gone into production. Following the incomplete development of the heavier Mil Mi-12 (prototypes known as Mil V-12) in the early 1970s, work began on a new heavy-lift helicopter, designated Izdeliye 90 ("Project 90")[1] and later allocated designation Mi-26. The new design was required to have an empty weight less than half its maximum takeoff weight.[2] The helicopter was designed by Marat Tishchenko, protégé of Mikhail Mil, founder of the OKB-329 design bureau.[3] The Mi-26 was designed as a heavy-lift helicopter for military and civil use, and was to replace earlier Mi-6 and Mi-12 heavy lift helicopters, with twice the cabin space and payload of the Mi-6, then the world's largest and fastest production helicopter. The primary purpose was to move military equipment like 13 metric ton (29,000 lb) amphibious armored personnel carriers, and mobile ballistic missiles, to remote locations after delivery by military transport planes such as the Antonov An-22 or Ilyushin Il-76. The first Mi-26 flew on 14 December 1977[4] and the first production aircraft was rolled out on 4 October 1980.[1] Development was completed in 1983, and the Mi-26 was in Soviet military and commercial service by 1985.[2] A helicopter is a type of rotorcraft in which lift and thrust are supplied by rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft would usually not be able to take off or land. The capability to hover efficiently for extended periods of time allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft cannot perform. The word helicopter is adapted from the French language hélicoptère, coined by Gustave de Ponton d'Amecourt in 1861, which originates from the Greek helix/helik- (ἕλιξ) = "twisted, curved"[1] and pteron (πτερόν) = "wing".[2][3][4] English-language nicknames used for helicopters include chopper, helo and whirlybird. Helicopters were developed and built during the first half-century of flight, with the Focke-Wulf Fw 61 being the first operational helicopter in 1936. Some helicopters reached limited production, but it was not until 1942 that a helicopter designed by Igor Sikorsky reached full-scale production,[5] with 131 aircraft built.[6] Though most earlier designs used more than one main rotor, it is the single main rotor with anti-torque tail rotor configuration that has become the most common helicopter configuration. Tandem rotor helicopters are also in widespread use due to their greater payload capacity. Quadrotor helicopters and other types of multicopter have been developed for specialized applications. Russia Listeni/ˈrʌʃə/ or /ˈrʊʃə/ (Russian: Россия, tr. Rossiya, IPA: [rɐˈsʲijə] ( listen)), also officially known as the Russian Federation[7] (Russian: Российская Федерация, tr. Rossiyskaya Federatsiya, IPA: [rɐˈsʲijskəjə fʲɪdʲɪˈrat͡sɨjə] ( listen)), is a country in northern Eurasia.[8] It is a federal semi-presidential republic, comprising 83 federal subjects. From northwest to southeast, Russia shares land borders with Norway, Finland, Estonia, Latvia, Lithuania and Poland (both with Kaliningrad Oblast), Belarus, Ukraine, Georgia, Azerbaijan, Kazakhstan, China, Mongolia, and North Korea. It shares maritime borders with Japan by the Sea of Okhotsk and the U.S. state of Alaska across the Bering Strait. At 17,075,400 square kilometres (6,592,800 sq mi), Russia is the largest country in the world, covering more than one-eighth of the Earth's inhabited land area. Russia is also the world's ninth most populous nation with 143 million people as of 2012.[9] Extending across the entirety of northern Asia and much of Eastern Europe, Russia spans nine time zones and incorporates a wide range of environments and landforms. An aircraft is a machine that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil,[1] or in a few cases the downward thrust from jet engines. The human activity that surrounds aircraft is called aviation. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, propulsion, usage and others.

• published: 22 Jul 2014
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