What happened
During an attempted short field landing, the pilot of Cessna 185F was unable to maintain directional control. The aircraft departed the runway, ground looped, and dragged a wing.
After the accident, the pilot reported that the tailwheel had developed a vibration or shimmy during the landing roll. As the aircraft began to veer off the runway, the pilot attempted to correct the deviation by applying opposite rudder and brake pressure. These inputs were insufficient to stop the aircraft from leaving the paved surface.
The investigation
The post-accident examination revealed that the tailwheel assembly exhibited signs of excessive vibration during the ground roll. This instability contributed significantly to the loss of directional control. No other mechanical failures were identified as primary factors in the departure.
Findings
Contributing factors included the pilot's inability to maintain directional control due to the tailwheel shimmy and the subsequent ground loop. The short field landing technique may have exacerbated the instability, but the primary issue was the mechanical vibration of the tailwheel assembly.