On June 19, 1996, at 1350 central daylight time, a Schweizer SGS 2-33AK, N65809, operated by the Civil Air Patrol, was substantially damaged when it impacted a sign during takeoff at the Coles County Airport in Mattoon, Illinois. The pilot and student pilot reported no injuries. The local, public use, training flight originated about 1350. The flight was conducted under 14 CFR Part 91 in visual meteorological conditions. No flight plan was filed. According to statements provided by Civil Air Patrol personnel, the glider was being towed by a Cessna 172 at the wing flight encampment. As the glider and tow airplane accelerated down the runway, the glider "drifted left of centerline. The left wing was down and [the wing] collided with a plastic runway apron sign." The glider released from the tow airplane, departed the runway, and came to rest in a grassy area. The two pilots egressed uneventfully. The tow airplane aborted the takeoff uneventfully. Examination of the airplane revealed substantial damage to the left wing. No evidence of flight control malfunction or mechanical anomaly was reported.