Accident Description
During the landing roll of a tailwheel-equipped airplane, the pilot experienced a pronounced tailwheel shimmy. Despite applying elevator control in an attempt to correct the vibration, the airplane deviated to the right. The pilot applied left brake input, but the airplane quickly executed a ground loop to the right, during which the left wing contacted the runway surface.
Postaccident Findings
A postaccident examination revealed that the left tailwheel steering spring was missing. The pilot noted that the spring had been present and functioned normally during the preflight inspection and taxi before departure. Subsequently, crash fire rescue personnel conducting a runway inspection for damage located the left steering spring on the runway. Photographs provided by the pilot depicted the spring in an undamaged condition.
The airplane sustained substantial damage to the left wing structure.
Meteorological Information
The airport's automated weather observation station recorded wind from 160° at 7 knots approximately 47 minutes before the accident, and from 140° at 6 knots about 13 minutes after the accident. The pilot executed the landing on runway 27.