What happened
During an en route flight, the pilot noted that the engine oil temperature had fallen below standard operating levels. While attempting to adjust the left propeller control and subsequently attempting to feather the left engine, the pilot found that the engine RPM could not be altered. Shortly after, a popping sound was heard from the right engine, and the pilot notified air traffic control of a double power loss and the necessity of an emergency landing at Bradford.
While being radar vectored for the ILS runway 32 approach, the pilot reported a partial recovery of power. As the aircraft approached the outer marker and broke out of the clouds mid-field, the pilot initiated a right turn at the departure end of the runway. During this maneuver, the aircraft type descended into a group of trees, leading to a post-crash fire that destroyed the plane. A witness at the scene reported hearing backfiring sounds as the aircraft flew over the runway.
Findings
Post-accident inspections revealed that the landing gear was in the down position and the wing flaps were extended to 15 degrees. Neither propeller had been feathered at the time of the accident. While the left engine's fuel servo had to be used on the right engine due to impact damage, subsequent tests of both engines were successful. Although the right fuel servo was found to be running rich, investigators could not identify a specific mechanical failure capable of causing the reported power loss or the backfiring. The aircraft was unable to maintain altitude during the turn because the landing gear and flaps were not retracted, and the propellers were not feathered, which is required for single-engine performance according to the pilot's handbook. Weather conditions at the time of the accident included low ceilings, reduced visibility, and light snow.