Aviat Aircraft Inc S-1-11B N5111B accident near Chapmansboro, Tennessee

Probable cause

The pilot’s loss of airplane control while performing an aerobatic maneuver, which resulted in the airplane entering an inverted flat spin at an altitude too low for recovery.

NTSB analysis

The pilot was performing aerobatic maneuvers between 400 and 2,000 ft above ground level (agl) in an aerobatic practice box. A witness recorded several videos of the airplane as it flew, including a video that captured the final moments of the flight. In the last few seconds of the video, the airplane entered a climb and completed a 4-point aileron roll. The airplane continued to climb briefly after the roll before continuing out of the camera’s view. ADS-B data showed that the airplane’s altitude for this final maneuver was between 700 and 1,800 ft agl. The airplane reappeared on video in a rapid descent in an orientation consistent with an inverted flat spin. An increase in engine rpm could be heard during the final few seconds of the video and engine noise could be heard throughout the flat spin, even after the airplane disappeared below the tree line.

Postaccident examinations of the airframe and engine revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.

Based on the available information, it is likely that the pilot lost control of the airplane while practicing aerobatic maneuvers, and the airplane entered an inverted flat spin at an altitude too low for recovery.

Text from the NTSB. Open the NTSB docket for ERA24FA391 for the full record.