On August 16, 1999, at 1345 eastern daylight time, a Cessna 150G, N4061J, owned and piloted by a commercial pilot, sustained substantial damage during a precautionary landing to runway 27 (5,013 feet by 50 feet, dry asphalt) at the Toledo Suburban Airport, Lambertville, Michigan. The flight was operated under the provisions of 14 CFR Part 91 and was not on a flight plan. The pilot, who was the sole occupant, reported minor injuries. The personal flight originated at 1340 and was en route to the Ranchport Airport, Stony Ridge, Ohio. In his written statement, the pilot said that he failed to remove the aileron gust lock that was installed on the right aileron. The pilot stated that he noticed that the gust lock was still installed when he made his first left turn after takeoff. The pilot said that he was able to make shallow turns and that on final approach, he, "...thru habit...", started to extend the flaps at which time the aircraft "... veered left in spite of reversing the flaps." The pilot stated that he then was able to level the wings of the airplane, but the "...nose wheel sank in the soft ground and the plane went over on its back." The pilot did not report any preexisting mechanical discrepancies with respect to the accident airplane. The airplane came to rest in the soft farm field adjacent to runway 27. A postaccident examination of the aircraft revealed no anomalies that could be associated with a preexisting condition.