Overview
A non-certificated pilot was conducting visual patterns at an airport when the airplane's engine began to sputter and lost partial power. The pilot examined the fuel lines, which were clear, but observed air bubbles in the lines. Attempts to prime the engine to clear the air bubbles were unsuccessful.
Maneuvering and Impact
The pilot steered the airplane toward the runway in an attempt to land quickly. However, the airplane could not maintain level flight, so the pilot began a descending turn for the runway. Realizing that strong winds would prevent reaching the landing surface, the pilot elected to perform a forced landing to an open field. While maneuvering to land, a gust of wind increased the angle of bank, and the pilot lost control of the airplane. The airplane impacted terrain nose low with approximately 45 degrees of bank.
Damage
Substantial damage was sustained to the outboard portion of the left wing.
Previous Operation and Examination
The airplane was flown by the pilot and the previous owner prior to the accident without any problems. An examination of the fuel system and fuel lines did not reveal the source of air in the fuel lines.