SEA97LA022

During a maintenance test flight of a home built aircraft, the pilot apparently initiated an emergency landing on a gravel road. The road was bordered on both sides by tall trees. On the right side of the road, power lines (lower than tree top level) paralleled the road. During the descent, the right canard and right rear wing came in contact with the power lines. The airplane then collided with the road and came to rest off the right side of the road among the trees. Wreckage examination revealed evidence that the butterfly valve in the carburetor was in the closed position, and the throttle stop was positioned approximately 1/8-inch from the stop screw. The throttle arm clamping screw was loose, and the throttle arm rotated easily on the butterfly valve shaft. Mandatory safety wire that was to be applied to the throttle arm clamping screw had not been used, and the safety wire on the throttle arm clamping screw was slack and provided inadequate security. Friends of the pilot reported that approximately one week before the accident, he was having trouble with the fuel mixture; they presumed that the pilot had been making adjustments to the carburetor.

On October 29, 1996 approximately 1430 Pacific standard time, a home built Collier Q200, N200CQ, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided with a power line and trees near Estacada, Oregon. Visual meteorological conditions prevailed at the time and no flight plan was filed for the local flight. The airplane was substantially damaged and the private pilot, the sole occupant, was fatally injured. The flight had departed from the Valley View Airport, Estacada, shortly before the accident.

The aircraft maintenance logbooks indicate that the airplane was completed and signed-off as meeting the requirements for the issuance of a special airworthiness certificate on May 13, 1996. The logbook entries indicate that the pilot was making several adjustments to the airframe and engine up to the time of the accident.

Friends of the pilot reported that a week before the accident, the pilot had stated that he was having problems with the fuel mixture, and presumed that the pilot was test flying the airplane and making adjustments to the carburetor.

At the accident site, the Federal Aviation Administration (FAA) Inspector from the Hillsboro, Oregon, Flight Standards District Office, reported that it appeared that the pilot was trying to make an emergency landing. Evidence at the accident site indicates that the airplane was traveling in an easterly direction and descending at a steep nose down attitude to a gravel road. The road was bordered on both sides by tall trees. On the right hand side of the road, power lines lower than the tree top level paralleled the road. As the airplane descended to the road, the right canard and the right rear wing came in contact with the power lines. The airplane then collided with the roadway and broke into five major pieces. The wreckage distribution was measured over a distance of approximately 60 feet. The airplane came to rest off the right side of the road among the trees.

During the examination of the wreckage, the FAA Inspector found that the butterfly valve in the carburetor was in the closed position, and the throttle stop was positioned approximately 1/8-inch from the stop screw. The throttle arm clamping screw was loose and the throttle arm rotated easily on the butterfly's valve shaft. The bushing was a smooth split sleeve. The throttle arm clamping screw was found with no safety wire applied. The safety wire applied to the throttle arm clamping screw was slack and provided inadequate positive security.

FAA Airworthiness Directive 72-06-05 R2 applies to the Marvel Schebler carburetors and compliance is mandatory to prevent looseness or separation of the throttle arm (see attachment).

Toxicological analysis performed by the Civil Aeromedical Institute, Oklahoma City, Oklahoma, reported negative results from the tests.