What happened
During the initial climb phase, approximately 60 feet above the ground, black smoke was seen emitting from the left engine of the aircraft type. The aircraft maintained a nose-high attitude before the nose pitched downward and the plane rolled into an inverted position. Both occupants of the aircraft were killed in the subsequent impact with the terrain.
At the time of the accident, the landing gear and flaps were in the down position. It was noted that the aircraft had been out of service for approximately 14 years prior to this flight. During the operation, the crew consisted of two individuals: one seated in the left seat and another in the right seat. Evidence suggested an unconventional arrangement regarding the control of the elevators, ailerons, and rudders between the two occupants.
Findings
An inspection of the engine following the accident revealed significant damage to the supercharger assembly. Specifically, the impeller shaft was found to be bent and the related bearing had sustained damage. The investigation determined that maintenance procedures regarding the pre-oiling of the supercharger drive shaft bearing were not followed after the long period of inactivity.
Additionally, the investigation identified factors contributing to the loss of control. These included the incapacitation of the pilot in command due to medical issues and the inability to maintain minimum controllable airspeed (VMC) because an unqualified person was attempting to manage flight controls.