On May 14, 2010, about 1730 Pacific daylight time, a Cessna 180, N3142C, experienced a right main landing gear collapse during a runway excursion at Oregon's Owyhee Reservoir State Airport near Caldwell, Idaho. The owner/pilot was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The private pilot was not injured, and one passenger sustained minor injuries. The airplane sustained substantial damage to the right wing from impact forces. The cross-country personal flight departed Caldwell about 1700, with a planned destination of Owyhee. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that he landed on runway 13 with a direct left crosswind with a steady half windsock deflection. The airplane bounced once before settling onto the runway. He then went from two notches of flaps to one notch. During the landing roll, he had the ailerons deflected into the wind. He stated that the landing conditions required light right rudder and light right braking. The pilot reported that he had little or no response to the initial right brake application. He applied more pressure, and the brake pedal went all the way down to the cabin floor with no braking action. He pumped the brake several times, but they did not activate. The airplane veered toward the side of the runway. The pilot stated that the airplane was fully loaded, and he did not want to risk aborting the landing at this point and possibly going into the lake, which was along the runway's left side. He had been to this airport many times, and indicated that he was past his preplanned go/no-go abort point for the conditions encountered. The airplane departed the left side of the runway surface into brush and rough terrain. The airplane collided with one ditch that was parallel to the runway, and bounced; the right main landing gear collapsed on ground contact. The airplane bounced across a second ditch, and came down on the right wing. The airplane slid another 30 feet before coming to a stop. The pilot stated that there were no signs of brake fluid leakage during his preflight inspection on the brake assembly or on the hangar floor. The right brake functioned normally during taxi and departure. He noted that although the wreckage was on top of the right main landing gear, the right tire was inflated, and the brake caliper was coated in brake fluid immediately after he exited the airplane. Due to the damage, investigators were unable to determine if a brake anomaly existed prior to the accident, and if so, why the malfunction occurred.