Accident Overview
On March 22, 2009, at about 1432 mountain daylight time, a Pilatus PC-12/45, registration N128CM, crashed approximately 2,100 feet west of runway 33 at Bert Mooney Airport (BTM) in Butte, Montana. The aircraft was diverting to BTM at the time of the accident. The pilot and all 13 passengers on board sustained fatal injuries. The airplane was substantially damaged by impact forces and a post-crash fire.
Flight Details
The airplane was owned by Eagle Cap Leasing of Enterprise, Oregon, and was operating as a personal flight under 14 Code of Federal Regulations Part 91. The flight had departed Oroville Municipal Airport, Oroville, California, on an instrument flight rules flight plan with a destination of Gallatin Field, Bozeman, Montana. Visual meteorological conditions prevailed at the time of the accident.
Probable Cause
The National Transportation Safety Board determined the probable cause of the accident to be: (1) the pilot’s failure to ensure that a fuel system icing inhibitor was added to the fuel before the flights on the day of the accident; (2) his failure to take appropriate remedial actions after a low fuel pressure state (resulting from icing within the fuel system) and a lateral fuel imbalance developed, including diverting to a suitable airport before the fuel imbalance became extreme; and (3) a loss of control while the pilot was maneuvering the left-wing-heavy airplane near the approach end of the runway.