In May 1999, in Plattsmouth, Nebraska, a two-seat homebuilt GP-4 crashed shortly after takeoff, killing its 73-year-old builder and 60-year-old passenger. Both men were licensed pilots. The builder had logged 181.4 hours in the airplane since first flying it 15 months earlier.
The weather at the time of the accident was clear and mild. According to witnesses, the airplane had climbed to about 500 to 700 feet agl after takeoff when it pitched over and entered a spin. The wreckage, approximately two miles from the end of the runway, gave indications of a near-vertical attitude at the time of impact. The engine and propeller were partially buried in the ground, with the oil pan, injector manifold and starter motor separated from the case and the crankshaft broken at the propeller flange. The engine was too badly damaged to be test run, but investigators could find nothing to suggest engine trouble as a possible cause of the crash. There was fuel-or at least “a fluid, blue in color”-in the fuel tank. Control continuity could be established, but it was impossible to determine the positions of the gear and flaps.
