Helio H 295 N6464V accident near Delta Junction, Alaska

Probable cause

A partial loss of engine power during takeoff for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

NTSB analysis

The airline transport pilot was departing on the air taxi flight from a remote, unimproved airstrip estimated to be about 850 ft long with 800 ft usable. He stated that the airplane seemed to accelerate normally but failed to become airborne at the departure end of the runway. The airplane impacted brush and trees, resulting in substantial damage to the right wing. The pilot suggested that the engine may not have been producing full power because, during a previous flight from the airstrip with a similar load, the airplane became airborne in about 600 ft. A review of the airplane's takeoff performance data revealed a takeoff ground run of about 480 ft for the conditions at the time of the accident.

A postaccident examination of the airplane revealed a missing hose clamp on the scat tube that joins the air filter assembly to the air box; however, a postaccident engine run revealed no evidence of any preimpact mechanical anomalies with the airplane's engine or systems.

Text from the NTSB. Open the NTSB docket for ANC15LA070 for the full record.