The pilot, who was also the owner/builder of the RV-7A, departed for a cross-country flight from his home airport near Jackson Hole, Wyo. Witnesses reported that, following departure, they observed the airplane climb to about 500 to 600 feet above ground level while it was maneuvering onto the downwind leg.
Witnesses also reported that the engine was producing abnormal sounds and appeared to lose power.
While on the downwind leg, the pilot declared an emergency and indicated that the engine had lost power; the air traffic controller then cleared the airplane to turn right onto the base leg and land.
Witnesses reported that, as the airplane was turning from the downwind to the base leg of the traffic pattern, a wing dropped and that the wings were then nearly perpendicular to the terrain.
Given the reported wind speeds, the plane would have encountered a 13- to 20-knot tailwind on the downwind leg and up to 20-knot right crosswind gusts while on the base leg. The tailwind would have resulted in a groundspeed that was much higher than the airspeed, and the pilot likely did not recognize that the airspeed was low.
The airplane subsequently made a rapid descent and hit terrain in a nose-low attitude, killing the pilot and a passenger.
Ground scar analysis and wreckage fragmentation revealed that the airplane descended in a steep 45°, nose-down attitude before it hit terrain, consistent with a loss of airplane control.
The NTSB determined the probable cause as a loss of engine power for reasons that could not be determined because post-accident examination revealed no mechanical malfunctions or failures that would have precluded normal operation.
Also causal was the pilot’s failure to adequately compensate for the wind conditions, which resulted in his failure to maintain adequate airspeed and his subsequent loss of airplane control while maneuvering within the traffic pattern for landing.
NTSB Identification: WPR13FA405
This August 2013 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.