Accident Details
The aircraft was departing on a required maintenance test flight following the replacement of both engines. Witnesses reported that the takeoff roll and initial climb appeared normal. However, at about 500 feet above ground level, the airplane entered a right bank that continued until the wings were vertical and the nose dropped through. The airplane then impacted the ground in an inverted, steep nose-down attitude.
Investigation Findings
Examination of the wreckage revealed that the right engine had been secured and feathered. The subsequent investigation did not find any evidence of pre-impact failure or malfunction of either engine or any of the airframe systems. Engine mounting and rigging continuity could not be established due to impact damage. Evidence indicated that the landing gear was retracted and that the left spoiler was deployed at impact. The rudder trim was found in the neutral position. The pilot was a principal in the operator's organization and not one of the regular line pilots.
Probable Cause
The official probable cause was determined to be: "The shutdown of one engine for undetermined reasons, and the pilot's failure to maintain VMCA during a critical phase of flight. A factor in the accident was the pilot's improper emergency procedure." The emergency procedure taught in transition training is to use rudder trim as soon as possible after engine failure to preclude deployment of spoilers.