The commercial pilot departed on a local flight and began a 120-mph cruise climb. After the RV-4 cleared some high terrain, the pilot leaned the engine fuel-air mixture, but the engine began to operate roughly.
He enriched the mixture, and the engine began to operate smoothly, but then lost total power.
The pilot performed emergency procedures, which included an attempted engine restart.
He said he pumped the throttle twice and the engine responded with “two small bursts of 500-600 rpms,” but then there was no additional engine power.
He made a forced landing to a private airfield in Montrose, Colorado, but was unable to reach the runway, and the airplane hit terrain and farm equipment.
A post-accident examination of the airplane fuel system revealed no anomalies. The carburetor could not be tested because it was destroyed during the accident sequence. A post-accident engine examination showed no evidence of pre-impact mechanical malfunctions or abnormalities. Thus, the reason for the total loss of engine power could not be determined.
Probable cause: The total loss of engine power for reasons that could not be determined.
NTSB Identification: CEN18LA068
This January 2018 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
