The pilot reported that, during a test flight, the Zenith CH701 encountered moderate turbulence so he decided to return to the airport in Snohomish, Wash.
While turning to the crosswind leg in the pattern, the plane suddenly banked sharply and descended uncontrollably.
The pilot was able to regain control about 500 feet above ground level, and managed to turn the plane to the downwind leg, but he continued to have difficulty maintaining control.
He then decided to make an emergency off-airport landing to a field. During the landing roll, the plane hit obstructions and nosed over. The wings and fuselage were substantially damaged and the pilot sustained minor injuries.
After the accident, the pilot reported that the loss of aircraft control was due to a jammed rudder for undetermined reasons.
The NTSB determined the probable cause as a jammed rudder control while maneuvering in the pattern for reasons that could not be determined. No follow-up examination was conducted due to a lapse in agency funding and subsequent government shutdown.
NTSB Identification: WPR14CA004
This October 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.