SEA94LA142

At the start of an aerobatic maneuver, the wings were observed fluttering just prior to the separation of the right wing. During the post crash inspection, evidence was found to indicate aileron flutter. The ailerons were also found to be out of balance.

On June 8, 1994, at 0930 mountain daylight time, a WAR Focke-Wulf 190, N25074, experienced an in flight break-up, three miles southwest of the Salt Lake City, Utah, Number 2 airport. Visual meteorological conditions prevailed at the time and no flight plan was filed. The private pilot was fatally injured and the airplane was destroyed. The flight had originated from Salt Lake City for the local flight.

A Federal Aviation Administration Inspector from the Salt Lake City Flight Standards District Office reported that he was present at the scene to observe the pilot for an aerobatic check out. The inspector stated that the airplane was in a shallow descent and increasing airspeed from 120 mph to approximately 150 mph, at 300 feet above ground level, when both wings began to flutter. The inspector stated that both wings appeared to flutter approximately one to two feet up and down for two to three seconds when the right wing separated at mid span. The airplane continued to descend in a steeper descent angle to ground impact.

The owner of the airplane reported that the pilot had removed the ailerons and had them painted sometime in the fall of 1993. The pilot then re-installed and balanced the ailerons.

During the wreckage inspection, evidence was found to indicate that the ailerons had experienced flutter and were substantially out of balance.

The wreckage distribution path measured approximately 1,320 feet and was located in an open field. At 310 feet and 500 feet, sections of the right wing were found. At 1,037 feet, a 25 foot long ground disturbance was noted. At 1,093 feet, parts of the left wing were noted, along with sections of the fuselage and fuel tanks that extended to 1,148 feet, where the right side elevator and sections of the left wing were found. At 1,173 feet, sections of the wing main spar were found. At 1,253 feet, the engine and propeller were found, along with sections of the empennage.

Maureen J. Frikke, M.D. of the Office of the Medical Examiner, Salt Lake City, Utah, reported that the cause of death to the pilot was from blunt force injuries of the head, torso, and extremities. Toxicological samples taken at the time were analyzed, and the result of that analysis was negative.