Primary finding
Probable cause
The pilots inadvertent encounter with a downdraft, which resulted in the airplane impacting trees.
Investigator assessment
Analysis narrative
During the takeoff climb, when the airplane reached an altitude of 35 feet, it encountered a downdraft caused by trees on the west side of the runway. The airplane seemed to "sag," was unable to continue its climb, and impacted the tree line. The pilot reported no mechanical deficiencies with the airplane. Witnesses also reported that the takeoff and initial climb appeared normal; however, at about 30 feet the airplane did not continue to accelerate or climb prior to impacting the trees.
Source record
Factual narrative
On June 17, 2005, at 0925 eastern daylight time, N13BH, an experimental built Taifun 17E motorglider was substantially damaged when it impacted trees during takeoff from Waterbury Airport (N41), Waterbury, Connecticut. The certificated commercial pilot was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local personal flight conducted under 14 CFR Part 91. According to the pilot, during his takeoff climb, when the airplane reached an altitude of 35 feet, the airplane encountered a downdraft caused by trees on the west side of the runway. The airplane seemed to "sag," was unable to continue its climb, and impacted the tree line. The pilot reported no mechanical deficiencies with the airplane. Witnesses also reported that the takeoff and initial climb appeared normal; however, at about 30 feet the airplane did not continue to accelerate or climb prior to impacting the trees.