What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
At approximately 12:40PM on 4/25/20 the aircraft was involved in repositioning a high tension power line via long line external load at approximately 150 ft AGL. The pilot reported a left yaw, engine out alarm, and hearing the engine winding down the pilot entered an autorotation. The pilot was able to release the belly band portion of the external load system, but was not able to release the cargo hook. The long line was not long enough for the aircraft to fully reach the ground. When the long line became tight it rolled the aircraft on its left side and caused substantial damage to the aircraft.
METAR kmtn 251654Z 15005KT 10SM SCT021 14/11 A3009
A engine inspection was performed by NTSB, haverfield aviation, and rolls royce. It was determined that unporting of fuel was the probable cause of engine shut down leading to the accident.
As the FAA filed it
AT APPROXIMATELY 12:40PM ON 4/25/20 THE AIRCRAFT WAS INVOLVED IN REPOSITIONING A HIGH TENSION POWER LINE VIA LONG LINE EXTERNAL LOAD AT APPROXIMATELY 150 FT AGL. THE PILOT REPORTED A LEFT YAW, ENGINE OUT ALARM, AND HEARING THE ENGINE WINDING DOWN THE PILOT ENTERED AN AUTOROTATION. THE PILOT WAS ABLE TO RELEASE THE BELLY BAND PORTION OF THE EXTERNAL LOAD SYSTEM, BUT WAS NOT ABLE TO RELEASE THE CARGO HOOK. THE LONG LINE WAS NOT LONG ENOUGH FOR THE AIRCRAFT TO FULLY REACH THE GROUND. WHEN THE LONG LINE BECAME TIGHT IT ROLLED THE AIRCRAFT ON ITS LEFT SIDE AND CAUSED SUBSTANTIAL DAMAGE TO THE AIRCRAFT.
METAR KMTN 251654Z 15005KT 10SM SCT021 14/11 A3009
A ENGINE INSPECTION WAS PERFORMED BY NTSB, HAVERFIELD AVIATION, AND ROLLS ROYCE. IT WAS DETERMINED THAT UNPORTING OF FUEL WAS THE PROBABLE CAUSE OF ENGINE SHUT DOWN LEADING TO THE ACCIDENT.
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 N9159F · 2
Matched to the same aircraft by N-number and date.