Flight Maneuvers
The Champ 7-GCBC was observed conducting repeated spin maneuvers. According to witnesses, spins were performed on all five flights the pilot had made since checking out in the aircraft, accumulating 3.4 hours of total flight time.
Witness Observation
A witness reported seeing the airplane heading straight down and spinning clockwise. The witness noted that the aircraft was near the altitude at which it had recovered from a previous spin when a piece of the plane separated.
Postcrash Examination
Examination after the accident revealed that the outboard right wing tip cap and some attached wing fabric had detached from the aircraft during flight. The forward and aft right wing spar structure were found at the ground impact site of the fuselage. The right wing forward spar exhibited upward bending deformation and splintering just outboard of the forward wing strut attachment point.
Previous Accident History
NTSB records indicate that the same aircraft had been involved in an accident on June 13, 1977, in Alaska. However, no aircraft records could be located to determine whether any damage occurred to the right wing in that event. An examination of the right wing spar structure showed that it was within the dimensional tolerances established by the manufacturer.