Mechanical & Engine Failure · NTSB ERA12FA093

Wing John R Wittman Tailwind — Fulton, NY

1 fatal
DateDecember 1, 2011
LocationFulton, NY
AircraftWing John R Wittman Tailwind (amateur-built)
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceApproach-VFR pattern downwind Loss of engine power (partial)
Pilot age64
Pilot total time760 hrs · Building experience
Time in type1 hrs
Fatalities1

Probable cause

The pilot's failure to maintain adequate airspeed, which resulted in an aerodynamic stall. Contributing to the accident was a partial loss of engine power due to the formation of carburetor ice.

NTSB findings

  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
  • Environmental issues-Conditions/weather/phenomena-Temp/humidity/pressure-Conducive to carburetor icing-Response/compensation - F
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Airspeed-Not attained/maintained - C

What happened

According the spouse of the pilot, the purpose of the flight was for him to become more familiar with the airplane in order to complete the required 40 flight hours of the phase one operating limitations. According to several witnesses, they heard the engine "sputter" and saw the airplane pitch nose down and descend through trees before impacting the ground. Such a descent is indicative of an aerodynamic stall. A postaccident examination of the airplane revealed no anomalies that would have precluded normal operation of the airframe or engine. Based on the temperature and dew point at the time of the accident, the conditions were favorable for serious carburetor icing at a cruise power setting. The carburetor heat control was in the full forward or "closed" position. The witness statements about the engine, as well as the favorable conditions for serious carburetor ice formation, suggest a partial loss of power. The pilot, still becoming familiar with the handling characteristics of the airplane, likely became preoccupied with restoring full engine power and maneuvering the airplane toward the airport in order to land and unintentionally entered an aerodynamic stall.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →