On June 22, 2011, about 1730 mountain daylight time, an Inhofe/Davis (Van's Aircraft) RV-8, N4546Y, departed the runway during landing at Sheridan County Airport, Sheridan, Wyoming. The pilot was operating the airplane under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91. The private pilot and passenger were not injured. The tailwheel-equipped airplane sustained substantial damage. The cross-country flight departed South Grand Lake Regional Airport, Ketchum, Oklahoma, about 1215 central daylight time. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that prior to landing on runway 050 he checked the Automated Surface Observation System (ASOS), which reported light winds from 030 degrees magnetic. He performed an uneventful left downwind approach, with an extended downwind segment. He then selected full flaps, and performed a slip maneuver during the final approach. Just after the main landing gear made contact with the runway, the airplane began to drift to the left. He countered with light application of the right rudder pedal, with unsuccessful results. He then applied increasing right rudder pedal pressure and the airplane began to swerve to the right. The airplane veered across the runway, and onto the opposite verge. As the tailwheel touched the ground, he applied left pedal pressure and the airplane rejoined the runway, coming to rest on a heading of 270 degrees. Examination of the airplane revealed scuff marks on the outer rim of the right wheel, and structural damage to the right side of the fuselage at the intersection of the wing root.