Background
A friend of the copilot reported that the multiengine airplane was making its first flight since the copilot, who held only a single-engine rating, purchased it five years earlier. The purpose of the flight was to practice touch-and-go landings. A pilot with a multiengine rating occupied the left seat, while the single-engine-rated copilot flew from the right seat.
Accident Sequence
On the day of the accident, the friend arrived at the airport and noticed the airplane was not in the traffic pattern. After several hours of concern, the friend reported the airplane missing to local authorities. The wreckage was located the following morning in a heavily wooded area approximately one mile from the airport. There were no witnesses to the accident.
Post-Accident Examination
Examination of the wreckage revealed that the left propeller displayed signatures indicative of low rotational speed at impact, suggesting that the left engine may have lost at least partial power. In contrast, the right propeller showed signatures consistent with high rotational speed and power at the time of impact. The left engine's fuel servo was heavily contaminated with sediment, and the fuel pump exhibited weak suction and compression. Either or both conditions could have reduced the left engine's performance during the flight. Additionally, the airplane was found with its wing flaps extended, the landing gear not retracted, and the left engine's propeller not feathered.
A representative from the airplane's type certificate holder stated that, depending on the takeoff weight, the airplane generally could not maintain level flight during an engine-out condition unless the flaps and landing gear were retracted and the failed engine's propeller was feathered. Given the purpose of the flight and the post-accident findings, it is likely that while maneuvering in the airport traffic pattern, the left engine lost power and the airplane subsequently impacted trees and terrain. The configuration of the wing flaps, landing gear, and unfeathered left propeller likely degraded the airplane's single-engine performance.