Braathen SAFE Flight 239, also known as the Asker Accident (Norwegian: Asker-ulykken), was a controlled flight into terrain of a Fokker F28 Fellowship into Vestmarka in Asker, Norway, on 23 December 1972 at 16:33. The Braathens SAFE aircraft was en route on a scheduled flight from Ålesund Airport, Vigra and crashed during approach to Oslo Airport, Fornebu. Forty of the forty-five people on board the aircraft died, making it the deadliest civil aviation accident in Norway until Vnukovo Airlines Flight 2801 in 1996. According to Norwegian newspaper Dagbladet on 23 December 1992, a Danish citizen died of late complications in 1976.
The pilots took a short-cut during approach on runway 06 at Fornebu. Combined with false signals from the instrument landing system (ILS), this caused the pilots to misunderstand their location. This in turn led them to take an incorrect landing path, causing the plane to hit ground in a hilly area. The rescue operation was initiated almost immediately, but it took six and a half hours to find the aircraft. Three years later, the investigation commission concluded that various measures should be put in place to improve navigation, to avoid similar situations in which pilots misunderstood their location.
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