Melbourne

A commercial pilot with two passengers on a business flight was arriving at the destination airport in a light twin-engine airplane. The air traffic tower controller advised the pilot to follow a slower airplane that was on base leg. The controller subsequently asked the accident pilot if he could reduce his speed,"a little bit." The accident pilot responded that he was slowing down. Less than a minute later, the controller told the accident pilot that he was cleared to land. The accident pilot's last radio transmission was his acknowledgement of the landing clearance. The controller stated that he did not see the accident airplane other than on the radar scope, but did see a plume of smoke on the final approach course for the active runway. Ground witnesses described the airplane as flying slowly with its wings wobbling, turn right, and dive into the ground. The majority of the airplane was consumed by a post crash fire. Inspection of the flight controls and engines disclosed no evidence of any preimpact mechanical problems. Low speed flight reduces the margin between a safe operating speed and an aerodynamic stall. Wing "wobble" at low speeds is often an indicator of an incipient aerodynamic stall. Toxicological samples from the pilot’s blood detected diphenhydramine (a sedating antihistamine commonly known by the trade name Benadryl) at a level consistent with recent use of at least the maximum over-the-counter dose. Diphenhydramine is used over-the-counter for allergies and as a sleep aid, and has been shown to impair the performance of complex cognitive and motor tasks at typical doses. The FAA does not specifically prohibit the use of diphenhydramine by pilots, though Federal Air Regulation 91.17, states, in part: "No crewmember may act, or attempt to act as a crewmember of a civil aircraft...while using any drug that affects the person's faculties in any way contrary to safety..."

The airplane was equipped with two experimental Engine AIR Power Systems TSIVD-427, 500-horsepower, liquid-cooled, turbocharged, V8 engines. During previous flights, the right engine lost boost then overboosted intermittently, and attempted repairs were unsuccessful. The pilot elected to fly the airplane to its home base for further troubleshooting. During cruise flight, the pilot reported an engine was surging, declared an emergency, and received vectors toward the airport. The airplane collided into a field beside the airport runway and caught fire. The airplane had a total of 8 to 10 hours of flight time at the time of the accident. Records revealed that two days after the airplane's first test flight, the pilot flew the airplane from Melbourne, Florida, to an airport 336 nm miles away, then flew it to Canada to display it at a fly-in.The FAA operating limitations for the airplane restricted its operation to flight test only, which was proposed to consist of 100 flight hours, since the installation of the modified engines. No single-engine performance data was available for this airplane. Examination of the engines and accessories revealed extensive fire and impact damage. Continuity of the crankshaft, valves, rods, and pistons was established for the right engine by manually rotating the propeller reduction control unit.