What happened
The aircraft was operating the final leg of a scheduled commuter route when it impacted terrain in a densely forested region while conducting a visual flight rules approach toward Merrill Field in Anchorage, Alaska. The airplane struck the ground in an inverted position with a near-vertical descent angle.
The captain and the single passenger aboard were killed instantly upon impact. Prior to this specific flight segment, the aircraft's first officer had exited the plane several minutes before departure. During his time on board earlier that evening, he observed no evidence that the captain had engaged or utilized the auxiliary fuel tanks during previous flights.
The investigation
Mechanical and operational analysis focused on the fuel management procedures leading up to the crash. Data indicated that the aircraft's main fuel tanks contained a usable capacity of 100 gallons. Calculations suggested that by the time of the accident, the engines had consumed slightly more than this total amount.
Although significant fuel reserves remained in the auxiliary tanks, the system design required pilots to manually select these tanks before the engine quit to allow for a successful restart. The investigation found that the crew did not switch to the auxiliary supply in time.