On January 15, 2011, about 1705 eastern standard time, a Schweizer 269C-1, N21086, was substantially damaged after it became airborne and collided with the ramp at Witham Field Airport, Stuart, Florida. The helicopter was operated by Bristow Academy, Inc. The private pilot-certificated student pilot not injured. Day, visual meteorological conditions prevailed at the time, and a company visual flight rules flight plan was filed for the cross country, instructional flight. The flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. The flight originated at Tamiami, Florida about 1510. According to the operator, the helicopter was involved in a training exercise with another company helicopter. After landing on the ramp at SUA, the flight instructor assisted the student pilot in setting the collective friction and the student pilot set the cyclic friction. The instructor then transferred control to the student pilot and exited the helicopter. The student pilot remained in the cockpit to allow the engine to cool down for shutdown. As the instructor was being driven off the ramp on a line cart, he observed the helicopter become airborne and enter a spin to the left. The helicopter then collided with the ramp surface and came to rest on its right side. A pilot witness estimated that the helicopter attained a height of about 30 feet prior to the collision. The student pilot reported that, after the flight instructor had left the cockpit, he noticed that the helicopter got "light on [the] skids" and began a slight yaw to the right. He confirmed that the collective was all the way down and pushed slightly on the "already stiff cyclic (because of the friction)" to avoid the other helicopter. The helicopter then climbed, rolled right, and the main rotor blades began hitting the tarmac. The engine was still running after the rollover and he shut the engine down and exited the cockpit. An inspector with the Federal Aviation Administration responded to the accident site and inspected the wreckage, assisted by personnel from Bristow Academy. He reported that control continuity was confirmed to the collective, cyclic, and antitorque controls. The cyclic and collective friction adjustments operated normally. The main rotor blades sustained substantial damage from impact with the ramp surface. The fuselage, landing gear skids, and tail boom all exhibited substantial damage. The second helicopter received minor damage from flying debris. The operator reported that there was no mechanical failure or malfunction with the helicopter prior to the accident. Weather, recorded at SUA at 1647, included winds from 090 degrees at 12 knots, visibility 10 statute miles, few clouds at 4,000 feet, temperature 20 degrees C, dew point 10 degrees C, an altimeter setting of 30.15 inches Hg.