On October 29, 1994, at 1208 hours Pacific daylight time, an amateur built Glen A. Senecal 5151 (a.k.a. midget mustang), N5246G, collided with the terrain after experiencing an aileron in-flight flutter at Apple Valley Airport, Apple Valley, California. The pilot was performing low flybys during an air show at Apple Valley Airport. The airplane, registered to and operated by the pilot, sustained substantial damage. The certificated private pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. The flight originated at Apple Valley Airport at 1153 hours. National Transportation Safety Board investigators conducted a telephone interview with the pilot on October 29, 1994. The pilot said that the airplane developed a severe aileron flutter condition when it was at midfield. The pilot immediately landed the airplane with its landing gears extended. The airplane touched down on the runway, but exited the runway environment during the skid. The main landing gear collapsed when the airplane entered onto the soft terrain. The pilot said in the aircraft accident report that the aileron was unbalanced. He said this condition caused the flutter. A Federal Aviation Administration (FAA) operations inspector from the Riverside [California] Flight Standards District Office witnessed the accident. He told Safety Board investigators that the flutter was very obvious from his vantage point. He said that he examined the airplane immediately after the accident. His examination disclosed that the right aileron cable was loose.