Accident Overview
On the day of the accident, the aircraft departed on a takeoff that appeared normal to witnesses. During the climb, the engine backfired and emitted dark smoke. The aircraft then turned left, followed by a steep right turn, before colliding with a powerline and crashing.
Aircraft History and Fuel System Findings
The aircraft had been flown three times in 1982 and twice prior to the accident day in 1983. Its last refueling occurred in September 1982, and it was stored outdoors between flights. Examination of the fuel system revealed that the gas cap on the wing showed areas of rust and corrosion, preventing a tight seal. This condition could allow moisture from rain and melting snow to leak into the fuel tank.
On April 11, 1983, investigators cut into the left wing fuel tank for inspection. The bladder was severely wrinkled on the bottom, creating pockets large enough to trap approximately one gallon of water. With the aircraft parked in a level position, this trapped water would not reach the drain sump.
NTSB Recommendations
The National Transportation Safety Board has made recommendations to the Federal Aviation Administration regarding the presence of water in fuel and the evaluation of bladder-type fuel tanks.