On March 22, 2009, a Pilatus PC-12/45, N128CM, crashed near the approach end of runway 33 at Bert Mooney Airport (BTM), Butte, Montana. The airplane was owned and operated by Eagle Cap Leasing of Enterprise, Oregon, as a personal flight under the provisions of 14 Code of Federal Regulations Part 91. All 14 people on board the airplane were killed in the accident. There were no ground injuries. The flight departed Oroville Municipal Airport, Oroville, California on an instrument flight rules flight plan and was destined for Gallatin Field, Bozeman, Montana. The airplane was diverting to Butte at the time of the accident. Visual meteorological conditions prevailed at the time of the accident.
The probable cause of this accident was (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.
The safety issues discussed in this report address fuel system limitations, requirements for fuel filler placards, and guidance on fuel system icing prevention.
Safety recommendations concerning these issues are addressed to the Federal Aviation Administration (FAA) and the European Aviation Safety Agency. Previous safety recommendations concerning crash protection for airplane occupants and flight recorder systems were addressed to the FAA.