The helicopter was positioned on a trailer when the pilot initiated a takeoff from the trailer. The pilot reported that the helicopter began a yaw to the right upon liftoff. He attempted to correct the yaw, but the helicopter continued to yaw. The pilot managed to regain some control and made a hard landing. The pilot’s supervisor was in his office near the trailer when he heard rapid tone changes in the rotor noise. He ran outside and saw the helicopter settle to the ground. He glanced at the helicopter, and it appeared undamaged. While the helicopter was still running, he climbed into the co-pilot side of the helicopter and performed a functional check. All controls functioned properly, and the gauges indicated normal. He then repositioned the helicopter back onto the trailer without incident. The helicopter sustained substantial damage to the tailboom. The pilot reported that there were no mechanical malfunctions/failures of the helicopter that would have precluded normal operations.