Amateur-built MURPHY RENEGADE N210SQ accident near Guilford, Connecticut

Probable cause

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

NTSB analysis

The airline transport pilot stated that this was the first flight after the carburetors were inspected, repaired, and reinstalled on the engine. The pilot stated that he used automotive fuel with 5% ethanol and noted no water in the fuel during his preflight inspection. About 30 minutes into the flight, the engine lost total power, and the pilot made a forced landing to a field. During the landing, the airplane struck powerlines and came to rest in the field, which resulted in substantial damage to the forward section of the fuselage.

Earlier in the year, the pilot had the carburetors inspected and repaired twice as a result of a rough-running engine. Further, in a letter to the maintenance facility dated the month before the accident, he stated that he had the ignition modules replaced, spark plugs replaced, and multiple other engine components inspected because the engine continued to run "rough." The pilot stated that each time the carburetors were inspected, there was evidence of water in the fuel, and one of the fuel jets was corroded.

Postaccident examination of the engine revealed that the left idle mixture screw had a small amount of corrosion on it; otherwise, no anomalies were noted with the engine that would have precluded normal operation. If there was water in the fuel, it could have resulted in the engine running roughly on previous flights and possibly the loss of engine power on the accident flight. However, the pilot did not note water in the fuel during his preflight inspection on the day of the accident. Additionally, engine manufacturer guidance stated that the engine was permitted to operate with up to 10% concentrations of ethanol in the fuel, and the pilot was using automotive fuel with 5% of ethanol, so that likely did not lead to the rough-running engine.

Although the pilot reported various problems with the engine during the airplane's 90 flight hours before the accident, the postaccident examination of the engine did not reveal any evidence of malfunctions or failures that would have precluded normal operation; thus, the investigation was unable to determine the reason for the total loss of engine power.

Text from the NTSB. Open the NTSB docket for ERA17LA276 for the full record.