Primary finding
Probable cause
A partial loss of engine power for undetermined reasons.
Investigator assessment
Analysis narrative
The noncertificated pilot stated that, shortly after takeoff, the engine began to lose power, run roughly, and shake violently. He applied carburetor heat and selected the left fuel tank, then the right fuel tank before selecting both fuel tanks with no change noted. He reduced engine power to control the airplane shaking and conducted an emergency landing. During the emergency landing, the airplane sustained substantial damage to the wings and fuselage. A postaccident examination revealed that the fuel selector was improperly labeled. However, the examination of the engine, accessories, and the other fuel system components revealed no mechanical malfunctions or anomalies that would have precluded normal operation. As a result, the reason for the partial loss of engine power and the engine’s rough operation could not be determined.
Source record
Factual narrative
On February 27, 2022, about 1232 Alaska standard time, a Piper P-18 airplane, N99640, sustained substantial damage when it was involved in an accident near Wolf Lake Airport (4AK6), Wasilla, Alaska. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The noncertificated pilot stated that, after departure from 4AK6 and while the airplane was about 100 ft above ground level, the engine began to lose power, run roughly, and shake violently. To restore engine power, he applied carburetor heat and selected the left fuel tank and then the right fuel tank before selecting both tanks, but those actions did not restore power. He reduced engine power to control the airplane shaking and conducted an emergency landing. During the emergency landing, the airplane impacted a burn barrel and came to rest against a hangar, which resulted in substantial damage to the wings and fuselage. A postaccident examination revealed that the Maule-type fuel selector had been mislabeled. Specifically, the position labeled “both” was for the right tank, the position labeled “left” was the “off” position, the position labeled “right” was for the left tank, and the position labeled “off” was for both tanks. The examination of the engine, its accessories, and the other fuel system components revealed no mechanical malfunctions or anomalies that would have precluded normal operation.