Primary finding
Probable cause
the pilot's inadequate compensation for the changing wind conditions, and his failure to maintain directional control, which resulted in an inadvertent ground swerve. The sudden windshift was a related factor.
Investigator assessment
Analysis narrative
The pilot stated that he made an approach to land on the runway with a moderate crosswind. He stated that at about 3 feet above the runway, the wind died or reversed. The airplane bounced; during the bounce, the wind started to turn the airplane. The pilot was unable to control the directional change, and the airplane ground-looped, sustaining substantial damage.
Source record
Factual narrative
On July 12, 1996, approximately 1600 mountain daylight time, a Cessna 170B, N3156A, sustained substantial damage when it ground-looped during landing at Lewistown, Montana. The private pilot and his passenger were uninjured. A VFR flight plan was filed for the flight, which originated at Cut Bank, Montana about two hours earlier. The ELT did not actuate. The pilot stated that he had approached with a moderate crosswind, and at about 3 feet above the runway the wind died or reversed. The airplane bounced; during the bounce the wind started to turn the airplane. The pilot was unable to control the directional change and the airplane ground-looped, damaging the left wing tip and left elevator tip. . -