Before departure from a local airfield near Bishkek, Kyrgyzstan the An-2 was fueled with 900 kg (1200 liters) unleaded gasoline “Premium Euro-95”. On board the aircraft was some cargo (a spare wheel, tools, etc.), with a total mass of 415 kg. The takeoff weight (5120 kg) and centre of gravity (26,3% MAC) were within limits. The airplane took off at 12:47 local time. About one minute after takeoff the crew reported that they were returning to the aerodrome of departure due to loss of engine power. The power was then lost almost completely, forcing the crew to carry out a forced landing in an agricultural field. This field contained deep slots, perpendicular to the direction of flight. On touchdown the left hand landing gear collapsed, along with the left hand wings. The reason for the loss of engine power in flight, most likely, was a reduction in the filing of the gasoline due to clogging of fuel filters. The appearance, structure and nature of the impurities found in the fuel on the aircraft were not characteristic of impurities accumulated in the fuel supply system in normal operating conditions. The source of the impurities in aircraft fuel system could not be found.