On January 31, 2012, at 1142 central standard time, a Piper Aircraft, Inc., PA-22-135 single engine airplane, N2677A, impacted terrain and obstructions during initial climb at Sheridan Municipal Airport (9M8), Sheridan, Arkansas. The airplane was registered to and operated by an individual as a personal flight under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed. The private pilot was seriously injured and the passenger suffered minor injuries. The airplane was substantially damaged. At the time of the accident the flight was originating from 9M8 for a local flight. During climbout the nose of the airplane started to skid sharply to the left and the pilot lowered the nose to avoid stalling. The airplane descended and impacted terrain on the left side of the runway coming to rest upright in the edge of a tree line. The impact completely separated the engine and propeller from the fuselage and there was substantial damage to both wings, the forward fuselage, and the empennage. The pilot reported that during the initial climb the passenger had suddenly tensed up and the pilot was unable to move the rudder pedals to correct the nose-left skidding because of interference from the passenger who was stepping on the passenger side rudder controls. The passenger reported this was his first flight ever in any aircraft and added that he was certain that his feet were clear and he was not pressing on the rudder pedals. A postaccident examination confirmed flight control continuity and revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.