Champion 7GC N4861E accident near Rexburg, Idaho

Probable cause

A decrease in indicated oil pressure while maneuvering at low altitude for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation. Also causal was the pilot’s failure to maintain clearance from power lines during the precautionary landing to a field.

NTSB analysis

The owner/pilot had completed two touch-and-go landings in the tailwheel-equipped airplane at his home airport and then left the airport traffic pattern to overfly a property south of the airport. For the overflight, the pilot reduced the engine rpm to about 2,100 and operated at an altitude of several hundred feet above the ground. The pilot then noticed that the oil pressure indication had dropped to the bottom of the green arc. He increased the engine rpm but observed the oil pressure continue to decrease. He considered attempting to return to the airport but then decided against that due to the population density between the airport and his current position; he elected to conduct a precautionary landing in a field. On short final for the field, the pilot failed to see the power lines across the field. The airplane struck the power lines then landed hard in the field. Postaccident examination of the airplane and engine did not reveal any mechanical abnormalities or conditions that would account for the decreased oil pressure indication, and when the engine was rotated with the starter, the oil pump was observed to produce expected pressure on the gauge and to pump oil.

Text from the NTSB. Open the NTSB docket for WPR12LA200 for the full record.