Aviat Aircraft Inc A-1B N178WW accident near Heber City, Utah

Probable cause

The pilot's failure to maintain clearance from the ground during low-level maneuvering in mountainous/hilly terrain.

NTSB analysis

The pilot reported that he was practicing the procedures for making approaches to back-country remote airstrips and was flying in approach configuration about 40 to 60 feet over a mountain ridge. Although the wind was light and variable, just as the airplane was crossing the ridge it encountered a downdraft, which resulted in a sudden loss of altitude. Before the pilot was able to correct the descent, one of the airplane's main landing gear tires came in contact with the snow-covered terrain, which resulted in the airplane slowing down and flipping over onto its back. The accident sequence resulted in damage to the top of the rudder and to one of the wing lift struts. The pilot reported no mechanical failures or malfunctions with the airplane at the time of the accident.

Text from the NTSB. Open the NTSB docket for WPR11CA041 for the full record.