On July 28, 2009, about 1330 Pacific daylight time, a North American AT-6G tailwheel equipped airplane, N555Q, sustained substantial damage during landing roll and subsequent ground loop at the Ely Airport (ELY), Ely, Nevada. The private pilot, who occupied the front seat, and his passenger who occupied the rear seat, were not injured. Visual meteorological conditions prevailed for the cross-country flight, which was being operated in accordance with Title 14 Code of Federal Regulations Part 91, and a flight plan was not filed. The flight departed the Livermore Municipal Airport (LVK), Livermore, California, about 1045, with ELY as its destination. The pilot reported to the Safety Board investigator-in-charge (IIC) that he made a normal visual approach and smooth landing on Runway 30, lowered the tail at about 30 to 40 miles per hour, and applied brakes to slow the airplane. The pilot stated that after applying the brakes the airplane pulled to the right, and as the airplane was going off the right side of the runway onto what appeared to be hard ground, he turned off the fuel, mixture, mags, and master switch. The pilot reported that after the airplane exited the runway to the right onto softer desert ground, the left [main landing] gear "…caught in the soft sand, then failed. This caused the aircraft's left wing tip to touch the ground and bent the [propeller] on one side." The pilot also reported that the wind at the time of the accident was from 300 degrees at 7 knots. A post-accident examination of the airplane's left wing revealed that it had sustained substantial damage. The pilot reported to the IIC that prior to the accident he had discovered three separate reports from three separate owner/pilots of the accident airplane, which detailed multiple, ongoing "brake lock-up" problems and brake system incidents. No maintenance records were provided to the IIC during the investigation to indicate that there had been a previous problem with either brake. During a post-accident investigation, a Federal Aviation Administration (FAA) airworthiness aviation safety inspector examined both the left and right brakes. The inspector reported that both brakes had normal wear at the time of his inspection, the left and right wheel bearings had fresh grease and were in good condition, and that the left and right spindles had fresh grease with no sign of damage. Post-accident inspection of the airplane did not reveal any preexisting failure/malfunction which would have resulted in the loss of control.