Incident Overview
A Bellanca 17 30A Super Viking was destroyed during a maintenance test flight. The pilot, who was also a mechanic, had just completed an annual 100-hour inspection on the aircraft. The flight was intended as a test prior to delivery to the aircraft's owner, who was the pilot's brother.
Witness Accounts
One witness reported seeing the airplane momentarily in a slight climb at approximately 1,500 feet above ground level (AGL). When the witness looked again, the airplane was at about 500 feet AGL in a near-vertical dive. Two seconds before impact, the right wing folded back but did not separate. The witness's impression was that the pilot had performed a split S or wing-over maneuver.
Another witness observed the airplane at an angle approximately 15 degrees past vertical, with the right wing sheared off.
Pilot Background
The pilot was a former aerial applicator. He had built and reportedly performed aerobatics in a Pitts S 2S Special.
Investigation
The accident investigation did not determine a probable cause.