Primary finding
Probable cause
The loss of engine power for reasons that could not be determined because a postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.
Investigator assessment
Analysis narrative
The commercial pilot had completed his second agricultural application flight of the day in the airplane. As he was returning to the departure airport, the engine experienced a loss of power. The pilot conducted a forced landing to a field, and the airplane subsequently nosed over and came to rest inverted. An examination of the airframe and engine did not reveal any preimpact anomalies that would have precluded normal operation. The weather conditions at the time of the accident were conducive to serious icing only at glide power; the engine was likely operating at cruise power at the time of the power loss. The reason for the loss of engine power could not be determined.
Source record
Factual narrative
On April 18, 2015, about 1135 central daylight time, a Grumman G-164A airplane, N7951, was substantially damaged during a forced landing following a loss of engine power near Maysville, Oklahoma. The commercial pilot, the sole occupant, sustained minor injuries. The airplane was registered to a private individual and operated by Pro-Ag Service Inc., under the provisions of 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed for the flight, which operated without a flight plan. The local flight originated from the Pauls Valley Municipal Airport (PVJ), Pauls Valley, Oklahoma, about 1030.According to initial information obtained by the responding Federal Aviation Administration (FAA) inspector, the pilot had completed his second aerial application of the day and was returning to PVJ when the engine stopped producing power. The pilot performed a forced landing to a field. During the landing, the airplane nosed over resulting in substantial damage to both wings and the vertical stabilizer. An examination of the airframe and engine by the FAA inspector did not find any anomalies which would have precluded normal operation. A review of the carburetor icing probability chart located in Special Airworthiness Information Bulletin CE-09-35 found the airplane was operating in an area conducive only to serious icing only at glide power.