Incident Overview
During a preflight inspection, the pilot noted that the left brake felt weak. Checking the left brake hydraulic fluid reservoir revealed a low fluid level, which was then refilled. After the refill, the brake operated satisfactorily.
Flight and Landing
The pilot flew the aircraft to KY07 with the intention of further inspecting the brake. During the landing roll, the pilot experienced a loss of pressure in the left brake. In response, the pilot applied the right brake, which caused the aircraft to ground loop. The aircraft departed the side of the runway, struck a fence, and came to rest in a ditch.
Post-Incident Examination
An examination of the aircraft determined that the left brake line had been worn through due to chafing against a screw that secures the strut fairing. This wear led to the loss of brake fluid and subsequent brake failure.