19980621014429A

Engine quit shallow left turn. Unable restart. Landed in tall grass field. A wing caught on grass. Flipped over. (-23) according to the pilot, he was in a shallow banked left turn when the engine suddenly quit. He tried several times to restart the engine, but was not successful. He therefore elected to make a forced landing in a nearby field in which tall grass was growing. The aircraft touched own in an upright position, but one wing caught in the tall grass and the aircraft flipped upside down. (.4) during the assembly of the home-built aircraft, its wet-wing fuel tanks were sloshed with a sealer (randolph #802) that is not compatible with alcohol fuel additives. During the aircraft's three week engine test run and test flight sequence, jet-a fuel containing an ethanol fuel additive (prist) was in its fuel tanks. This resulted in the sloshing compound debonding from the fuel tank walls and partially blocking an in-line fuel filter. Because of this blockage, approximately 25 minutes into the fourth test flight, the aircraft experienced a total loss of power. During the subsequent forced landing, the aircraft nosed over when one of its wings became entangled in tall vegetation . During the investigation it was determined that the owner/builder, the test pilot, representatives of the company that helped mate the engine to the airframe, and the supplier of the engine/propeller/gearbox assembly, all of whom were present for the ground run and test flight sequence on that day, were not aware that an alcohol fuel additive may be present in some jet-a fuel at the time of purchase.