What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Description of the deviation:
privacy data omitted Was operated on a VFR flight plan. During take-off from runway 33 from kbtm (Bert Mooney field, Butte, MT) the pilot reported experiencing a strong left quartering wind gust, resulting in a loss of control, when the aircraft weathervaned into the wind and departed the left side of the runway during the take-off roll. The aircraft came to rest between the runway and parallel taxiway after a wing float touched the ground resulting in substantial damage to the aircraft.
Causal and/or contributing factors:
A substantial wind gust which was not forecasted or present during pre-flight planning or run-up ultimately caused the pilot to lose control of the aircraft during take-off roll. Pilot reported that the ground speed was "less than 25 mph when a left quartering wind gust caused the airplane to weathervane and depart the runway to the sod" the pilot stated that this is a known hazard in this aircraft make/model and that a majority of his flight experience was operating this aircraft in similar conditions, including at high altitude and temperature.
No ATC actions contributory to the event.
No recommendations for systemic corrective action.
Action taken to correct problem and prevent reoccurance:
Counseling
Sas #: T-NM05-FY24-0370
As the FAA filed it
DESCRIPTION OF THE DEVIATION:
^PRIVACY DATA OMITTED^ WAS OPERATED ON A VFR FLIGHT PLAN. DURING TAKE-OFF FROM RUNWAY 33 FROM KBTM (BERT MOONEY FIELD, BUTTE, MT) THE PILOT REPORTED EXPERIENCING A STRONG LEFT QUARTERING WIND GUST, RESULTING IN A LOSS OF CONTROL, WHEN THE AIRCRAFT WEATHERVANED INTO THE WIND AND DEPARTED THE LEFT SIDE OF THE RUNWAY DURING THE TAKE-OFF ROLL. THE AIRCRAFT CAME TO REST BETWEEN THE RUNWAY AND PARALLEL TAXIWAY AFTER A WING FLOAT TOUCHED THE GROUND RESULTING IN SUBSTANTIAL DAMAGE TO THE AIRCRAFT.
CAUSAL AND/OR CONTRIBUTING FACTORS:
A SUBSTANTIAL WIND GUST WHICH WAS NOT FORECASTED OR PRESENT DURING PRE-FLIGHT PLANNING OR RUN-UP ULTIMATELY CAUSED THE PILOT TO LOSE CONTROL OF THE AIRCRAFT DURING TAKE-OFF ROLL. PILOT REPORTED THAT THE GROUND SPEED WAS "LESS THAN 25 MPH WHEN A LEFT QUARTERING WIND GUST CAUSED THE AIRPLANE TO WEATHERVANE AND DEPART THE RUNWAY TO THE SOD" THE PILOT STATED THAT THIS IS A KNOWN HAZARD IN THIS AIRCRAFT MAKE/MODEL AND THAT A MAJORITY OF HIS FLIGHT EXPERIENCE WAS OPERATING THIS AIRCRAFT IN SIMILAR CONDITIONS, INCLUDING AT HIGH ALTITUDE AND TEMPERATURE.
NO ATC ACTIONS CONTRIBUTORY TO THE EVENT.
NO RECOMMENDATIONS FOR SYSTEMIC CORRECTIVE ACTION.
ACTION TAKEN TO CORRECT PROBLEM AND PREVENT REOCCURANCE:
COUNSELING
SAS #: T-NM05-FY24-0370
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other reports on N87583 · 2
Matched to the same aircraft by N-number and date.