The sport pilot reported that while the initial takeoff roll was normal, he noted that the Aeronca was not gaining airspeed and the engine was not developing full power. However, he decided to continue the takeoff.
He stated that, once he was committed to the takeoff, there seemed to be an even “greater loss of power.”
The airplane only reached 150′, and he decided to turn right to avoid a highway and power lines.
He initiated a 20° bank, and the plane stalled and then hit a bean field adjacent to the airport in Mahnomen, Minnesota.
Although weather conditions at the time of the accident were conducive to moderate icing at cruise power or serious carburetor icing at descent power, given the airplane was at takeoff power, it is unlikely that carburetor ice accumulated and caused the power loss.
The pilot’s decision to not abort the takeoff at the first sign of a loss of engine power resulted in a slow airspeed during the initial climb during a turn, which resulted in the aerodynamic stall.
Probable cause: The pilot’s failure to abort the takeoff after recognizing a partial loss of engine power during the takeoff roll and his subsequent inability to maintain adequate airspeed during a turn to avoid power lines, which resulted in an aerodynamic stall. The reasons for the loss of engine power could not be determined because post-accident examination of the engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.
NTSB Identification: CEN17LA238
This June 2017 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.