What happened
During the approach to land on runway 10, the pilot experienced engine surging in both engines. This malfunction caused the aircraft to oscillate about its vertical axis by approximately 15 to 20 degrees. To maintain alignment with the runway, the pilot applied full right rudder while simultaneously lowering full wing flaps and reducing engine power to decelerate.
As the aircraft passed over the end of the runway, the pilot further reduced engine power. At this point, the aircraft veered to the left and crashed into the grass located next to the runway. At the time of the accident, winds were recorded from 080 degrees at 18 knots, with gusts reaching 22 knots. The pilot did not transmit any reports of aircraft malfunctions to the ATC tower prior to the crash.
The investigation
A post-crash examination of the aircraft revealed that both propellers sustained damage consistent with powered rotation during the ground impact. However, a detailed examination of the engines provided no evidence of any mechanical failure or malfunction that would account for the engine surging reported by the pilot.