Primary finding
Probable cause
A loss of engine power for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation.
Investigator assessment
Analysis narrative
During a training flight, the flight instructor and the pilot receiving instruction were practicing procedures for a simulated engine failure. According to the pilot receiving instruction, when he attempted to reapply power the engine was unresponsive. They were forced to make an off-airport landing, which resulted in substantial damage to the right wing. During the postaccident examination, the engine was test run; no mechanical anomalies were revealed that precluded normal operation. The reason for the loss of engine power could not be determined.
Source record
Factual narrative
HISTORY OF FLIGHT On November 6, 2011, about 0955 Pacific standard time (PST), a Beech A36, N64Z, made a forced landing following a loss of engine power at Yucca Valley Airport, Yucca Valley, California. The owner/pilot was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The certified flight instructor (CFI) and private pilot undergoing instruction (PUI) were not injured; the airplane sustained substantial damage to the right wing. The local instructional flight departed Yucca Valley about 0925. Visual meteorological conditions prevailed, and no flight plan had been filed. The owner/PUI reported that they were performing a simulated loss of engine power. When he attempted to reapply power, the engine did not respond. They made a forced landing near the airport. During the landing, the right wing struck a road sign, and the landing nose gear separated from the fuselage. The PUI reported that the training flight had departed with approximately 35 gallons of fuel. During the recovery of the airplane, approximately 25 gallons of fuel was drained from both fuel tanks. On November 28, 2011, investigators examined the airplane and engine at Aircraftsman, Inc., Chino, California. The engine field run report is attached to the docket. The engine was inspected and the air induction filter box had sustained impact damage during the forced landing. No other damage to the engine was observed. After removing the damaged propeller a replacement propeller was installed. An external fuel supply was attached to the fuel valve, and the engine was started and ran with no abnormalities noted.