FTW96LA331

The experimental airplane was on its fifth flight. The pilot reported that about 15 minutes into the accident flight the airplane 'experienced flutter and began loosing altitude.' A few seconds before the forced landing, the engine lost power. The pilot reported that the airplane was controllable until the loss of engine power. The airplane impacted the ground in a 'yawed' attitude and tumbled, coming to rest in an inverted position. During the final approach for the forced landing, the upper right flaperon had departed the aircraft approximately 300 yards before the impact site. According to the pilot, who was also the builder of the airplane, he believed the flutter to be the result of his 'increasing the size of the flaperons from the designer's original design without a corresponding increase in the strength of the control system elements.' Contributing to this was the fact that the flaperons had not been balanced. Postcrash examination of the airplane revealed that the in-flight flutter had caused the upper right wing's fuel tank to rupture, and fuel had been spilled down the right side of the airplane. The fuel selector at the time of the accident was on the 'Right Upper' tank.

On August 02, 1996, at 1236 central daylight time, a Scott Glass Goose, N96GG, owned and operated by a private owner, was substantially damaged during a forced landing following a primary control surface structural failure near Aubrey, Texas. The private pilot, sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 personal flight. A flight plan was not filed for the local flight that originated at Lake Dallas, Texas, at approximately 1215.

The experimental airplane was on its fifth flight. According to the pilot, the prior four flights were without incident. The pilot reported that about 15 minutes into the accident flight, the airplane, "experienced flutter and began loosing altitude." The pilot elected to land the airplane in a field. A few seconds before the landing, the engine lost power. The pilot reported that the airplane was controllable until the loss of engine power. The airplane impacted the ground in a "yawed" attitude and tumbled, coming to rest in an inverted position. All wings of the bi-winged airplane were broken, and the fuselage was substantially damaged.

After the accident, the pilot discovered that during the final approach for the forced landing, the upper right flaperon had departed the aircraft approximately 300 yards before the impact site. According to the pilot, who was also the builder of the airplane, he believed the flutter to be the result of his "increasing the size of the flaperons from the designer's original design without a corresponding increase in the strength of the control system elements." Contributing to this was the fact that the flaperons had not been balanced.

Post crash examination of the airplane revealed that the in flight flutter had caused the upper right wing's fuel tank to rupture, and fuel had been spilled down the right side of the airplane. The fuel selector at the time of the accident was on the "Right Upper" tank.