Incident Summary
An aircraft experienced a left engine oil pressure warning shortly after takeoff from Örnsköldsvik Airport while climbing to 7,000 feet. The crew shut down the engine but were unable to feather the propeller. A fuse blew, causing only the right side of the instrument lights to remain functional. After being cleared to return, the crew completed a turn but on approach required full elevator and rudder deflection due to the unfeathered left propeller. The aircraft landed 30 meters left of the runway, rolled a few dozen meters, and came to rest. All 17 occupants escaped uninjured, while the aircraft was damaged beyond repair.
Flight and Failure
During initial climb after takeoff, the left engine oil pressure warning light illuminated. The crew shut down the affected engine. Attempts to feather the propeller were unsuccessful, and the failure caused a fuse to blow, disabling the left side instrument lights. The crew coordinated with air traffic control for a return to the airport.
Landing and Outcome
On final approach, the crew had to use full elevator and rudder deflection to compensate for the drag from the unfeathered propeller. The aircraft touched down 30 meters left of the runway centerline, then rolled a few dozen meters before stopping. All occupants evacuated without injury. Post-landing inspection revealed the aircraft was damaged beyond repair.
Probable Cause and Contributing Factors
The official investigation determined the probable cause was that the left propeller could not be feathered, creating drag that forced the crew to compensate with trim and rudder deflection, causing the aircraft to be misaligned on final approach. Contributing factors included: an oil leak in the left engine during initial climb prompting the shutdown; power supply problems because the left side was not isolated from the right side; wrong adjustment of the speed control trigger; and inadequate following of the checklist.