On 25 February 2009 a Boeing 737-800, flight TK1951, operated by Turkish Airlines was flying from Istanbul in Turkey to Amsterdam Schiphol Airport. There were 135 people on board. During the approach to the runway at Schiphol airport, the aircraft crashed about 1.5 kilometres from the threshold of the runway. This accident cost the lives of four crew members, and five passengers, 120 people sustained injuries. The crash was caused by a malfunctioning radio altimeter and a failure to implement the stall recovery procedure correctly.