NTSB Factual Report

HISTORY OF FLIGHT

On July 2, 1996, at 0855 hours Pacific daylight time, a Davis Challenger I CW, N75489, owned and operated by the pilot, crashed during its maiden flight at the Paso Robles Municipal Airport, Paso Robles, California. The experimental amateur built airplane was destroyed, and the private pilot was fatally injured during the personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The flight was originating at the time of the accident.

A witness reported observing the airplane's takeoff and crash. The witness stated that the takeoff roll appeared normal, but seconds after the airplane lifted off the runway, around 100 feet above ground level, a light colored small component separated from the upper surface of a wing and contacted the pusher wood propeller. One blade separated, the engine stopped operating, and the airplane porpoised up and down several times. Then, the airplane turned 90 degrees from its runway heading, pitched nose down, and impacted the ground while in a 45-degree nose down attitude.

The Federal Aviation Administration (FAA) coordinator performed an on-scene examination of the crash site. According to the FAA, a bent plastic (Lexan) strip was located about 300 feet downwind of the main wreckage and in close proximity to the separated propeller blade. An examination of the wreckage revealed that the strip had been attached to the upper surface of the wing's center section with Velcro self-adhesive tape. The adhesive material had failed to secure the strip to the wing.

The Lexan strip was rectangular in shape, and was designed to cover a gap in the fuselage forward of the engine assembly. The pilot purchased the homebuilt kit in November, 1995. Construction was completed the week preceding the accident flight. The pilot reportedly had performed taxi tests for about 1.5 hours preceding his first attempted takeoff.

PERSONNEL INFORMATION

According to the FAA, when the pilot last applied for an aviation medical certificate on November 29, 1994, he reported that his total flying experience was about 185 hours, and he had flown 5 hours during the preceding 6-month period. The FAA did not issue the pilot the requested certificate because of his cardiovascular condition.

MEDICAL AND PATHOLOGICAL INFORMATION

On July 5, 1996, an autopsy on the pilot was performed by the San Luis Obispo County Coroner's Office, San Luis Obispo, California.

The FAA performed toxicology tests on specimens from the pilot, and found evidence of drugs including chlordiazepoxide, diazepam, amitriptyline, atenolol and diltiazem in blood and liver fluid. No ethanol was detected.

According to the manager of the FAA's toxicology and accident research laboratory, these drugs may be prescribed for conditions including depression and hypertension. In brief, use of these drugs could adversely influence the pilot's mental processes, reaction time, and ability to control the airplane.

NTSB Probable Cause

the owner/builder/pilot's impairment of judgment and performance due to drugs which led to his improper handling of the airplane and failure to maintain an adequate airspeed margin above stall speed, resulting in an inadvertent stall/spin. A factor which contributed to the accident was the owner/builder/pilot's use of an inadequate adhesive material in the construction of the airplane which resulted in a portion of the wing root surface skin to debond, separate, and impact a propeller blade, which also separated.