LAX08CA293

The pilot made a normal landing but the airplane veered off the runway when the tail wheel made contact with the pavement. The airplane ground looped, sustaining damage to the left wing tip. The pilot said that rudder control inputs he made were ineffective in controlling the airplane. During a post-accident examination of the airplane, the pilot discovered that the bolts which attach the tail wheel assembly to the tail spring were sheared.

On September 10, 2008, about 1710 Pacific daylight time, an experimental amateur built Brubaker F1, N954CB, ground looped during landing at Truckee-Tahoe Airport (TRK), Truckee, California. The pilot/owner was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The certificated private pilot and one passenger were not injured; the airplane sustained substantial damage to the left wing tip. The cross-country personal flight departed Bountiful, Utah, about 1530. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that during a normal landing using runway 10 the airplane veered off to the right side of the runway when the tail wheel made runway contact. The pilot attempted to maintain directional control by applying full left rudder, but his rudder control inputs were ineffective. The airplane sustained substantial damage to the left wing tip, the left landing gear, and the tail wheel. The pilot stated that the airplane and engine had no mechanical failures or malfunctions during the flight. The pilot submitted a Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) on September 16, 2008. On October 3, 2008, the pilot submitted a modification to the original report following further examination of the airplane. The pilot reported that it appeared that the AN3 through bolts, which attach the tail wheel assembly to the tail spring, were sheared. According to FAA Advisory Circular AC 20-27F, Certification and Operation of Amateur-Built Aircraft, "Amateur builders are free to develop their own designs or build from existing designs. We do not approve these designs and it would be impractical to develop design standards for the wide variety of design configurations, created by designers, kit manufacturers, and amateur builders."