On April 21, 2000, at 1500 mountain daylight time, a Beech A36TC, N305MM, sustained substantial damage when the main landing gear collapsed during landing roll at Monument Valley, Utah. The private pilot and his passenger were not injured. The flight was operating under Title 14 CFR Part 91 and no flight plan was filed. The flight departed Farmington, New Mexico, at 1300. According to the pilot, during landing roll a wind gust ("whirlwind") was encountered which turned the aircraft 90 degrees and the main landing gear collapsed. Although no weather reporting stations were located in the area where the accident occurred, the National Weather Service had issued an Alert Bulletin, stating that turbulence was forecast for the area. The pilot provided information that the wings, fuselage, propeller, and the landing gear sustained damage. According to the FAA inspector who examined the pilot's log after the accident, the pilot was not current in landings in the past 90 days.