Accident Sequence
The student pilot reported that the flight was normal until a violent right yaw developed when the throttles were advanced to recover from a practice stall. The certified flight instructor (CFI) then took over the controls and attempted recovery, at which point a substantial loss of power occurred on both engines. A forced landing was made in a field, during which the left wing contacted trees and the aircraft was engulfed in flames.
Post-Accident Examination
Post-accident examination of the left engine failed to disclose any discrepancies. However, discrepancies were noted on the right engine: the fuel controller fuel line tee fitting was cracked around 50% of its circumference, characterized as ductile overload, and the turbocharger gasket on the inlet side of the turbine showed leakage on approximately 70% of the gasket area.
History of Fuel Vaporization
The aircraft had a history of symptoms of fuel vaporization, which subsided with use of the auxiliary fuel pump as suggested by the engine manufacturer. It is unknown whether the auxiliary pump was used during this accident.