Piper PA 28-181 N9681K accident near Waukesha, Wisconsin

Probable cause

The loss of engine power for reasons that could not be determined because no anomalies were identified during postaccident examination.

NTSB analysis

The pilot reported that he had entered the airport traffic pattern for landing. When the airplane was abeam the approach end of the runway, he reduced power, applied carburetor heat, and confirmed that the auxiliary fuel pump was on. When the airplane was on the base leg of the traffic pattern, the pilot attempted to increase engine power, but the engine did not respond; he stated that advancing the throttle to full did not result in an increase in power. He attempted moving the engine and carburetor heat controls to no avail. While attempting the remedial action, he turned toward the runway and declared an emergency. The airplane impacted trees short of the runway. A postaccident examination of the airplane confirmed that fuel was present. The engine was rotated and compression was verified on all cylinders, and the magnetos showed spark that was confirmed at all of the spark plug leads. No mechanical reason for the loss of engine power was discovered. At the time of the accident, the temperature and dew point were 24 degrees C and 17 degrees C, respectively. According to a carburetor icing probability chart, the temperature and dew point were in a range of susceptibility for moderate icing at cruise power settings and serious icing at descent power settings. Because the pilot reported using carburetor heat during the landing approach, the reason for the loss of engine power could not be determined.

Text from the NTSB. Open the NTSB docket for CEN14LA443 for the full record.