On November 3, 1993, at 1446 mountain standard time, a Bellanca BL17-31ATC, N9516E, was substantially damaged when the right main landing gear collapsed after the airplane departed the side of the runway at Stevens Field, Pagosa Springs, Colorado. The pilot and his passenger were not injured and the aircraft sustained substantial damage. Visual meteorological conditions prevailed and no flight plan was filed for this personal flight which departed from Plainview, Texas, at 1246 central standard time. According to the pilot, the left brake locked during the landing roll and the aircraft went off the left side of the runway. The pilot said that during this excursion, the right main landing gear collapsed and the nose gear was distorted. The airframe sustained damage around the right main gear mount. Examination of the aircraft by an Federal Aviation Administration inspector provided no evidence of a brake system malfunction. Examination of the runway provided witness marks of skidding of both main tires and scrubbing of the nose tire in a curve to the left.