What happened
During a pleasure flight, the pilot transmitted that they intended to perform maneuvers beyond straight and level flight. Witnesses near the scene reported hearing a loud pop, followed by observing the Schweizer sailplane entering a vertical descent without its left wing. The aircraft subsequently collided with the terrain.
The investigation
Investigators examined the wreckage and found that the left wing spar had broken two feet from the wing root. A metallurgical examination of the spar determined that the failure was caused by a positive (up) overload.
Findings
Post-accident investigation revealed that the aircraft was placarded for a pilot weight not to exceed 166 lbs, while the pilot in command weighed 210 lbs. Additionally, a Schweizer service bulletin restricts this specific sailplane from performing aerobatic maneuvers.