Probable cause
(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.
NTSB analysis
The Safety Board's full report is available at http://www.ntsb.gov/investigations/reports_aviation.html. The Aircraft Accident Report number is NTSB/AAR-11-05.
On March 22, 2009, about 1432 mountain daylight time, a Pilatus PC-12/45, N128CM, was diverting to Bert Mooney Airport (BTM), Butte, Montana, when it crashed about 2,100 feet west of runway 33 at BTM. The pilot and the 13 airplane passengers were fatally injured, and the airplane was substantially damaged by impact forces and a postcrash fire. The airplane was owned by Eagle Cap Leasing of Enterprise, Oregon, and was operating as a personal flight under the provisions of 14 Code of Federal Regulations Part 91. The flight 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.
Text from the NTSB. Open the NTSB docket for WPR09MA159 for the full record.
Event
- Date
- Mar 22, 2009
- Type
- Accident
- Place
- Butte, Montana
- Nearest airport
- Bert Mooney Airport (BTM)
- Highest injury
- Fatal
- Fatal injuries
- 14
- Weather
- Visual (VMC)
- Light
- Day
Pilatus PC-12/45
- N-number
- N128CM
- Category
- Airplane
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Personal
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.