Incident Overview
While conducting an ILS/DME approach to Ketchikan Airport, the pilot encountered adverse weather conditions, including a low ceiling, rain, turbulence, and thunderstorm activity. In limited visibility, the pilot failed to recognize that the aircraft's altitude was too low. The airplane subsequently struck a mountain and crashed, bursting into flames. All four occupants on board were killed.
Probable Cause and Contributing Factors
The official investigation determined that the probable cause of the accident was a controlled collision with ground due to improper IFR operation. Several contributing factors were identified: the pilot attempted an operation that exceeded his experience and ability level; there was a lack of familiarity with the aircraft; and weather conditions included a low ceiling, rain, and turbulence associated with thunderstorms.
Summary
This accident underscores the challenges of operating in poor weather conditions during an instrument approach. The pilot's failure to maintain adequate altitude resulted in a collision with terrain. The investigation cited both human factors and environmental conditions as contributors to the accident.