On October 30, 2003, at 1500 eastern standard time, a Thocker, Vans RV-4, N44NW, registered to a private owner, operating as a 14 CFR Part 91 personal flight, collided with the runway on takeoff roll at the Causey Airport, Liberty, North Carolina. Visual meteorological conditions prevailed and no flight plan was filed. The airplane received substantial damage. The commercial pilot reported no injuries. The flight originated on October 30, 2003, from Causey Airport, Liberty, North Carolina, at 1500. The pilot stated he started his takeoff roll on runway 20. The first part of the rotation was normal and he continued to release back pressure but shortly after that the stick would not move forward. The airplane became airborne and achieved an extremely nose high attitude. He thought he might have an elevator trim problem and pushed the trim lever forward with negative results. The airplane was approaching a stall, entered an uncontrolled descent and collided with the ground. He exited the airplane and returned a short time later. He reached in the airplane and tried to move the control stick. It moved freely and correctly. A witness stated he observed the airplane on takeoff. The tail came up almost as soon as the takeoff roll began. The rotation was abrupt and the airplane came off the ground in a nose high attitude. The nose of the airplane was observed to pitch up, the airplane stalled, veered to the right and then back to the left. The nose dropped and the airplane continued descending to the left and collided with the ground. The accident pilot stated in a subsequent statement that while the airplane was being taxied to the runway with the tail wheel bumping over the sod, that the prop wash might have moved the seatbelt over the stick in it's rear most position. Examination of the flight control system revealed there was no evidence of a control system failure. Review of the Van's Aircraft RV-4 Performance Data reveals the RV-4 will stall at 54 mph in the clean configuration. No stall speed is listed for the landing configuration.