No fatalities

28 Aug 2009: PIPER PA-12 — Michael Johnson — Gonvick, MN

Gonvick, MN, United States

On 28 Aug 2009, a PIPER PA-12 operated by Michael Johnson was involved in an aviation accident near Gonvick, MN. No fatalities were reported. Investigators recorded the probable cause as: A loss of engine power due to carburetor icing as a result of the pilot's failure to use carburetor heat. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 1778583330Data APIEditorial standards

A float-equipped airplane experienced repeated engine RPM drops and a loss of power during a practice flight for a sea rating. The pilot performed a forced landing in a field, where the aircraft nosed over, buckling the fuselage. Post-accident engine tests revealed no anomalies, but weather conditions were conducive to carburetor icing, which the pilot did not address.

Accident Sequence

The pilot, who held a total of 1,859 flight hours with 12 hours in the accident airplane, planned a one-hour flight to practice for his airplane sea rating in a float-equipped aircraft. During the flight, the engine lost 100 revolutions per minute (RPM) on four or five separate occasions. At approximately 1,000 feet above ground level, the engine sputtered and lost power entirely. The pilot executed a forced landing to a field. Upon touchdown, the airplane impacted the terrain and nosed over.

Post-Accident Examination

Inspection of the aircraft revealed that the fuselage was buckled. A subsequent postaccident inspection and test run of the engine failed to identify any mechanical anomalies.

Weather Conditions

The nearest weather reporting facility, located 10 nautical miles southwest of the accident site, recorded a temperature of 22 degrees Celsius (C) and a dew point of 18 degrees C at the time of the accident. Review of a carburetor ice probability chart indicated that these temperature and dew point values were conducive to serious icing conditions at glide power. The airplane was equipped with carburetor heat, but the pilot stated that he did not use it during the flight.

Contributing factors

Effect on equipmentNot used/operatedPilot