NTSB Factual Report

The pilot reported that during cruise flight into "wispy clouds," the engine started to "run rough" then lost all power. About 800 ft. agl, he restarted the engine, but it quit again. He attempted to restart the engine multiple times but was unsuccessful, so he selected a gravel road for landing. During the landing, the airplane ground looped into a ditch.

The pilot added that he did not apply carburetor heat during the accident flight.

The biplane sustained substantial damage to the right wing.

The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.

The automated weather observation station located 25 nautical miles away from the accident site reported that, about the time of the accident, the wind was from 170° at 5 knots, visibility of 7 statute miles, clouds broken at 4,800 feet above aerodrome level, temperature at 77°F, and dew point at 75°F.

Review of the Federal Aviation Administration Carburetor Icing Chart for the given temperature and dew point revealed that the conditions were conducive to "serious icing (glide power)." (For more information, see Special Airworthiness Information Bulletin CE-09-35 in the public docket.)

NTSB Probable Cause

A total loss of engine power due to the pilot's failure to apply carburetor heat in conditions conducive to carburetor icing and his subsequent failure to maintain directional control during a forced landing.