On November 1, 2009, at 1610 eastern standard time, an experimental L-13 Blanik glider, N1142, sustained substantial damage when it impacted terrain after it released the tow line about 200 feet above ground level during takeoff climb from the Geauga County Airport (7G8), Middlefield, Ohio. The certified flight instructor (CFI) and student pilot received serious injuries. The 14 Code of Federal Regulations Part 91 instructional flight was departing 7G8 on a local flight. Visual meteorological conditions prevailed and no flight plan was filed. The CFI reported that he was following the student pilot on the controls during the takeoff climb. He observed the tow plane rock its wings indicating to the glider to “wave off”. The CFI took control of the glider and stated, “It’s my airplane.” He released the tow line and turned 180 degrees to return to the airport. The CFI lowered the nose to increase aircraft energy. He reported that the student pilot grabbed the controls and pulled back on the stick. He could not overpower the student on the controls and the airplane started to spin left. He picked up the left wing by applying opposite rudder. The glider impacted a tractor dealer’s parking lot. Meanwhile, the tow airplane returned to the airport without incident. A Federal Aviation Administration inspector interviewed the student pilot. The student pilot stated that she observed several puffs of black smoke coming from the tow airplane. The CFI told her that he had the controls and started a turn back to the airport. She stated that she felt they were too low to the ground and she panicked, grabbed the controls, and pulled back on the stick. She heard the CFI shout, “Don’t stall, don’t stall,” but it was too late and the airplane impacted the ground. The inspection of the glider revealed that it sustained substantial damage to the fuselage and wings. No pre-impact anomalies were noted.