Austrian Airlines Flight 901

Austrian Airlines Flight 901 was a flight from Vienna, Austria to Moscow, USSR (now Russia) via Warsaw, Poland. On the night of 26 September 1960 the aircraft operating the flight, a Vickers Viscount, crashed near Moscow while on its approach to land, killing 31 of the 37 passengers and crew on board.

Aircraft
The aircraft was a Vickers Viscount 837 four-engined turboprop airliner registered OE-LAF. The aircraft had first flown on 10 February 1960 and had been delivered new to Austrian Airlines about two weeks later, seven months before the crash.

Accident
The aircraft departed Warsaw with six crew and 31 passengers on board. The flight was on approach to land on runway 07 at Sheremetyevo International Airport in the northern outskirts of Moscow when it crashed in a rural area 11 km short of Sheremetyevo's runway near the town of Krukovo.

Investigation
The investigation determined that the crew thought that the aircraft was higher than it was and that it flew into trees during its approach and crashed. Investigators found that the captain's altimeter (the left-hand altimeter) was adjusted to show a different altitude to the copilot's altimeter. The left altimeter's barometric sub-scale had been set to a pressure that would have resulted in it reading zero feet on the ground at Sheremetyevo. However, the sub-scale on the copilot's altimeter was set to a pressure that would have resulted in it reading the airport's height above mean sea level when on the ground at Sheremetyevo. This was against the airline's operating procedures, but the investigation could not determine the reason for the discrepancy.