Amateur-built CCX-1865 N510US accident near Big Creek Ranger Station, Idaho

Probable cause

The pilot’s failure to identify the wet landing surface and his subsequent inability to maintain directional control and stop during landing on the unimproved grass runway, which resulted in a runway excursion and unintentional ground loop.

NTSB analysis

The pilot of the tailwheel-equipped airplane reported that he conducted multiple passes over the landing area to assess the landing conditions and did not see that the grass surface was wet. Upon touchdown, he noticed the airplane did not decelerate as expected due to wet tires, and the brakes had little effect. The airplane veered off its intended path, heading toward steep downhill terrain. To prevent continuing uncontrollably downhill, the pilot attempted an intentional ground loop by applying full right rudder and power. Subsequently, the airplane tipped left and stopped before reaching the steeper terrain, resulting in substantial damage to the left aileron and left elevator. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR23LA246 for the full record.