Mi-26: Russia's airborne 'cow'

BBC News Online profiles the Russian military Mi-26 helicopter which crashed in Chechnya on Monday, with the loss of at least 100 lives.

Nicknamed "the cow", the Mil Mi-26 is the heaviest and most powerful helicopter in the world.

Conceived in the early 1970s, the Mi-26 is designed to carry up to 20 tons of troops and equipment.

It was designed to have a maximum takeoff weight one and a half times that of any other helicopter.

The Mi-26 is a mainstay of the Russia military

The Mi-26 can lift more than twice the payload of an American CH-47 Chinook.

Its weightlifting capabilities are more comparable with a C-130 Hercules aircraft.

Although mainly in military use, the Mi-26 was originally intended for civil use.

Development work began in 1977 and the first machines rolled off assembly lines in 1980.

The first machines are believed to have become operational in 1985.

The huge, slow-flying craft has seen extensive service in Chechnya since the mid-1990s.