N924WY

HISTORY OF FLIGHTOn November 5, 2016, about 0756 mountain daylight time, an experimental, amateur-built Stamper RV-10 airplane, N924WY, impacted terrain following a loss of control shortly after takeoff from the Dubois Municipal Airport (DUB), Dubois, Wyoming. The private pilot was fatally injured, and the airplane was destroyed. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91. Day visual meteorological conditions prevailed, and no flight plan was filed for the local test flight, which was originating at the time of the accident.

A witness reported that he saw the airplane takeoff from runway 28 and that the airplane's right gull-wing cabin door rotated open upon liftoff. The witness saw the pilot reach for the fully open door with his right hand and heard a momentary reduction of engine power. He then saw the airplane descend momentarily before he heard an increase in engine power and saw the airplane level-off over the runway. He reported that the pilot continued to reach for the open cabin door as the airplane overflew the remaining runway about 35 ft above ground level. The witness then saw the airplane's left wing and nose drop suddenly, which he described as an aerodynamic stall. The airplane descended into terrain, and there was a large explosion upon impact. PERSONNEL INFORMATIONAccording to Federal Aviation Administration (FAA) records, the 44-year-old pilot held a private pilot certificate with ratings for airplane single-engine land, airplane single-engine sea, and instrument airplane. His most recent FAA second-class medical certificate was issued on September 17, 2015, with no limitations.

The pilot's flight history was established using his logbook. The final logbook entry was dated October 10, 2016, at which time he had accumulated 1,482.1 total hours of flight experience. According to his logbook, the pilot had flown 119.3 hours, 81.6 hours, 30.6 hours, and 1.3 hours during the year, 6 months, 90 days, and 30 days before the accident, respectively. There was no record that he had flown during the 24 hours before the accident. The pilot had logged 1.8 hours in the accident airplane. His most recent flight review, as required by 14 CFR 61.56, was completed on March 17, 2016.

According to the company that insured the airplane, in October 2016, the pilot reported having a total flight experience of 1,500 hours of which 40 hours were in Van's Aircraft RV-6 airplanes and 4 hours were in Van's Aircraft RV-10 airplanes. The pilot reported having flown 2 hours in the accident airplane. AIRCRAFT INFORMATIONThe airplane, serial number 40146, was a single-engine, low-wing, monoplane of conventional aluminum construction. The airplane was powered by an experimental, 260-horsepower Aero Sport Power IO-540-D4A5 reciprocating engine, serial number 1542. The engine provided thrust through a constant-speed, three-blade, Whirl Wind Aviation 375RV composite propeller, serial number 375-106. The four-seat airplane was equipped with a fixed tricycle landing gear, wing flaps, and had a maximum allowable takeoff weight of 2,700 pounds.

The pilot had assembled the airplane from a kit purchased from Van's Aircraft. The airplane was issued a special airworthiness certificate on April 23, 2016. The airplane's hour meter was destroyed during the postimpact fire, which precluded a determination of the airplane's total service time at the time of the accident. According to available information, the airplane likely had accumulated 10 to 12 hours since receiving the airworthiness certificate and had not completed the Phase I flight test requirements. The last condition inspection of the airplane was completed on April 23, 2016. A postaccident review of available maintenance records found no history of unresolved airworthiness issues. The airplane had a total fuel capacity of 60 gallons distributed between two wing fuel tanks. A review of fueling records established that the fuel tanks were topped-off before the accident flight.

The airplane was equipped with two upward-opening gull-wing cabin doors. Each door was affixed to the roof of the cabin with two steel hinge assemblies. The upper fuselage cabin and both doors were constructed of composite material. Each door lock assembly consisted of a rack and pinion latch mechanism, and two latch pins were set into the lower section of the door panel. Each door was locked by rotating a door handle affixed to the pinion gear, and as the gear rotated, the latch pins extended through a polyethylene pin block and into pin sockets recessed into the forward and aft cabin doorjambs. The doors were not equipped with an additional safety latch mechanism provided by the airframe kit manufacturer. Alternatively, the doors were equipped with an aftermarket center latch system, which consisted of a rotating semicircular cam that worked in conjunction with the rack and pinion latch mechanism. As the door handle rotated into a locked position, the center cam rotated against a polyethylene block installed in the lower doorjamb to provide an additional center latch point.

The gull-wing cabin doors were fitted with a latch indicator system supplied by the airplane kit manufacturer. The system consisted of four magnetic reed switches located near the doorjamb pin sockets. A cylindrical magnet was installed into the end of each latch pin, and the locations of the reed switches were adjusted such that they would activate when the latch pins extended into the doorjamb. The latch circuit was designed so that the instrument panel indicators extinguished when the latch pins were extended into the locked position. METEOROLOGICAL INFORMATIONA postaccident review of available meteorological data established that day visual meteorological conditions prevailed at the accident site. At 0755, about 1 minute before the accident, the DUB automated surface observing system reported: wind 270° at 6 knots, 10 miles surface visibility, a clear sky, temperature 0°C, dew point -8°C, and an altimeter setting of 30.29 inches of mercury. AIRPORT INFORMATIONThe airplane, serial number 40146, was a single-engine, low-wing, monoplane of conventional aluminum construction. The airplane was powered by an experimental, 260-horsepower Aero Sport Power IO-540-D4A5 reciprocating engine, serial number 1542. The engine provided thrust through a constant-speed, three-blade, Whirl Wind Aviation 375RV composite propeller, serial number 375-106. The four-seat airplane was equipped with a fixed tricycle landing gear, wing flaps, and had a maximum allowable takeoff weight of 2,700 pounds.

The pilot had assembled the airplane from a kit purchased from Van's Aircraft. The airplane was issued a special airworthiness certificate on April 23, 2016. The airplane's hour meter was destroyed during the postimpact fire, which precluded a determination of the airplane's total service time at the time of the accident. According to available information, the airplane likely had accumulated 10 to 12 hours since receiving the airworthiness certificate and had not completed the Phase I flight test requirements. The last condition inspection of the airplane was completed on April 23, 2016. A postaccident review of available maintenance records found no history of unresolved airworthiness issues. The airplane had a total fuel capacity of 60 gallons distributed between two wing fuel tanks. A review of fueling records established that the fuel tanks were topped-off before the accident flight.

The airplane was equipped with two upward-opening gull-wing cabin doors. Each door was affixed to the roof of the cabin with two steel hinge assemblies. The upper fuselage cabin and both doors were constructed of composite material. Each door lock assembly consisted of a rack and pinion latch mechanism, and two latch pins were set into the lower section of the door panel. Each door was locked by rotating a door handle affixed to the pinion gear, and as the gear rotated, the latch pins extended through a polyethylene pin block and into pin sockets recessed into the forward and aft cabin doorjambs. The doors were not equipped with an additional safety latch mechanism provided by the airframe kit manufacturer. Alternatively, the doors were equipped with an aftermarket center latch system, which consisted of a rotating semicircular cam that worked in conjunction with the rack and pinion latch mechanism. As the door handle rotated into a locked position, the center cam rotated against a polyethylene block installed in the lower doorjamb to provide an additional center latch point.

The gull-wing cabin doors were fitted with a latch indicator system supplied by the airplane kit manufacturer. The system consisted of four magnetic reed switches located near the doorjamb pin sockets. A cylindrical magnet was installed into the end of each latch pin, and the locations of the reed switches were adjusted such that they would activate when the latch pins extended into the doorjamb. The latch circuit was designed so that the instrument panel indicators extinguished when the latch pins were extended into the locked position. WRECKAGE AND IMPACT INFORMATIONThe initial point-of-impact was in an open field about 1,675 ft past the runway 28 departure threshold and 183 ft left of the extended runway centerline. The debris path was 67 ft long oriented on a 210° magnetic heading between the initial point-of-impact and the main wreckage. A ground impact crater, containing propeller fragments, was located about 44 ft from the initial point-of-impact. The main wreckage consisted of the fuselage, wings, and empennage. The cabin, including the cockpit instrument panel, was destroyed during the postimpact fire. Both wings exhibited damage consistent with ground impact. The empennage was relatively undamaged. A flight control continuity check was not possible due to the extent of damage; however, all observed...