Overview
On a non-scheduled domestic flight from Tenerife to Las Palmas, an aircraft took off from runway 30 at Tenerife Airport at 1830 hours under an IFR flight plan. The aircraft carried 32 occupants, most of whom were Scandinavian tourists. During the initial climb, the aircraft disappeared from the view of the tower controller while in low cloud, approximately 500 meters before the end of the runway.
Sequence of Events
According to the tower controller, the pilot acknowledged the last instructions two minutes after takeoff and did not re-establish contact afterward. The aircraft was not seen again until moments before the accident, which witnesses indicated occurred between 1834 and 1840 hours. It was later determined that the airplane entered a dive and crashed several kilometers from the airfield. All 32 occupants were killed.
Official Findings
The investigation concluded that the cause of the accident was unknown and classified it as "undetermined." However, several possible reasons for the aircraft entering a spin were listed. One probable cause was a failure of the suction pump or vacuum system, which would have rendered the artificial horizon, directional gyro, and turn-and-bank indicator inoperative. Such a failure, aggravated by turbulence, could deprive the pilot of the means to control the aircraft, potentially leading to a stall. Another possibility was flying into very severe turbulence with loss of control resulting in a stall. Engine failure was not considered probable, although a malfunctioning propeller was not ruled out. It was noted that the pilot likely would have alerted the tower in the event of an emergency, but might not have done so if instruments failed or severe turbulence occurred, as attention would be focused on restoring normal attitude.