Amateur-built RV 6 N616RV accident near Pima, Arizona

Probable cause

A total loss of engine power for reasons that could not be determined based on the available evidence.

NTSB analysis

The pilot reported that, while the airplane was traveling westbound at 1,100 ft above the ground, the engine stopped producing power without warning. The propeller continued to windmill. The pilot initiated a 180° turn back toward the airport and attempted to restart the engine but was unable to do so. The pilot decided to land the airplane onto a nearby cotton field. When the airplane touched down, the landing gear sunk into the soft dirt, and nosed over.

During a postaccident examination, the engine was able to be started, but it operated poorly and was smoking before it stopped producing power. Disassembly of the engine revealed that the two rotors and five of the six apex seals remained intact. The remaining apex seal was fractured in half. It was not possible to determine whether the apex seal fractured before or during the accident sequence. No other anomalies were revealed.

The available evidence for this accident precluded a determination of whether the fractured apex seal caused the total loss of engine power.

Text from the NTSB. Open the NTSB docket for WPR20LA040 for the full record.