What happened
While climbing to cruise altitude and passing 2,000 feet MSL, the aircraft experienced a total loss of engine power. The pilot attempted a forced landing in a region of marshy tundra, during which the airplane nosed onto its back.
The investigation
A postaccident inspection of the aircraft focused on the engine and throttle assembly. Investigators discovered that the throttle control lever had disconnected from the throttle arm. The inspection revealed significant wear between the throttle arm and the connecting hardware bushing.
Records indicated that a newly overhauled engine had been installed 334 hours prior to the accident. Additionally, maintenance logs showed that company mechanics had complied with Service Bulletin SEB95-15R1, titled 'Throttle Lever Inspection,' which mandates a visual inspection for wear between the arm and bushing every 50 hours or 12 months. The most recent inspections under this bulletin occurred 56 hours, 163 hours, and 268 hours before the accident.