Incident Overview
During flight, the pilot observed oil accumulating on the windscreen. Despite the obstruction, he continued to the destination and proceeded to land on Runway 16. The windscreen was covered in oil, and the pilot described the wind conditions as "squirrely winds." The wind was estimated from 150 degrees at 15 knots, gusting to 22 knots, with light turbulence.
Loss of Control
During the landing roll, the pilot lost control of the aircraft due to the combination of unfavorable wind conditions and restricted forward visibility caused by the oil on the windscreen. The aircraft subsequently ground looped and exited the left side of the runway.
Post-Incident Examination
An examination of the aircraft revealed that the oil filler extension tube had separated from the engine case. The pilot stated that a similar problem occurred in May 1979, and at that time maintenance personnel had epoxied the oil filler extension tube back into the engine.