Champion 7ECA N9541S accident near Chugiak, Alaska

Probable cause

The pilot's failure to maintain proper airspeed and his exceedance of the airplane's critical angle of attack during a steep low-altitude turn following a loss of engine power, which resulted in an aerodynamic stall and subsequent loss of control at too low of an altitude to recover. The reason for the loss of engine power could not be determined because postaccident examination revealed no mechanical malfunctions that would have precluded normal operation.

NTSB analysis

According to multiple witnesses at the airport, they observed the airplane perform several touch-and-go landings throughout the late morning and early afternoon on the day of the accident. They added that the pilot then landed and taxied to a local fuel vendor's facility and refueled. The pilot then departed. Two witnesses who were near the departure runway reported that, after the airplane departed, they heard the engine making a "pop pop" sound and that it then appeared to lose power. Another witness near the runway reported hearing the engine "sputtering" and added that the airplane appeared to stall. All the witnesses reported that they observed the airplane turn right steeply, that its right wing and nose dropped abruptly, and that it then descended in a steep, nose-down attitude, consistent with an aerodynamic stall. A postimpact fire immediately ensued, which destroyed the airplane.

A postaccident examination of the airframe and engine revealed no mechanical malfunctions that would have precluded normal operation. The witnesses reported hearing noises consistent with an engine misfiring and it was likely losing power; however, the reason for the loss of engine power could not be determined based on the postaccident examination. After the loss of engine power, the pilot attempted a steep turn at low altitude, during which he failed to maintain proper airspeed and exceeded the airplane's critical angle of attack, which resulted in an aerodynamic stall and a loss of control at too low of an altitude to recover.

Text from the NTSB. Open the NTSB docket for ANC16FA057 for the full record.