On March 3, 2002, at 1130 mountain standard time, an experimental Fairchild 24W-46, N77618, nosed over during the turnoff from landing at the Marana Northwest Regional Airport (AVQ), Marana, Arizona. The airplane, owned and operated by the private pilot under the provisions of 14 CFR Part 91, sustained substantial damage. The pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. The cross-country flight departed the Casa Grande Municipal Airport, Casa Grande, Arizona, about 1100, and was destined for AVQ. No flight plan had been filed. In the pilot's written statement, he indicated that he made a normal wheel landing. On rollout he applied rudder and then brake to maintain directional control. He stated that the left brake locked up and the airplane went over on it's back. During retrieval of the airplane, the brake pads were loosened. Both the owner and the person assisting with the retrieval noted that there was no clearance of the brake pads. When they attempted to push in the piston to release the disk they found it could not be moved. They also noticed that the brake pads were discolored. No further discrepancies were noted with the brake system.