Diamond Aircraft Ind Inc DA 20-C1 N877CT accident near Wurtsboro, New York

Probable cause

The pilot’s performance of aerobatic maneuvers at low altitude and his failure to maintain airspeed, which resulted in an aerodynamic stall.

NTSB analysis

Witnesses observed the airplane takeoff and begin performing maneuvers similar to aerobatics at low altitude over the runway. The airplane descended in a forward slip until it was about 30 feet above the runway, accelerated, and pulled up to an estimated 70 degree nose-up attitude. The airplane leveled out and performed a “swoop down” maneuver, followed by a right turn toward an empty parking lot. It then entered a nose dive over the parking lot and impacted the ground. The pilot reported that the engine lost power, and he was making a forced landing in the parking lot. However, none of the witnesses reported hearing engine problems, and one witness specifically stated that he did not “hear any mechanical problems with the airplane.” Examination of the wreckage did not reveal any abnormality that would have prevented normal operation of the airplane’s flight controls. Examination of the engine revealed evidence that, at some time, water had contaminated the fuel system. No other abnormalities were noted during examination of the engine. The pilot reported that he had drained some water from the airplane’s fuel system during the preflight inspection and that he had continued to drain fuel until no water was detected. Based on the pilot’s report that he had drained all water from the fuel system, the finding of no discrepancies (other than the evidence of water contamination) with the engine, and the lack of witness reports of engine problems, it is likely that the engine was operating throughout the aerobatic maneuvers.

Text from the NTSB. Open the NTSB docket for ERA11LA306 for the full record.