What happened
On August 5, 2017, at approximately 13:50 EDT, a Burkhart Grob Flugzeugbau G-102 Club Astir IIIB glider, registration N102BK, was being towed from Marion Municipal Airport (MNN) in Marion, Ohio. During the initial climb, the pilot experienced an issue with the canopy and subsequently released the tow line. The glider struck a tree and impacted a bean field, resulting in one serious injury and no fatalities.
The pilot reported that due to an error during pre-takeoff checks, the canopy was not properly latched. After climbing a few hundred feet, the canopy opened. While attempting to secure the canopy, the pilot lost sight of the Cessna 150 tow airplane and released the tow line to perform a right turn.
A witness observed the flight and noted that the glider's left and right-wing spoilers were extended during the climb. The witness stated that the glider released from the tow plane at approximately 150 to 200 feet above ground level (agl) and attempted a 180-degree turn back toward the runway with the spoilers still deployed. The tow pilot also reported feeling the aircraft being jerked during the climb and observed the glider in a high nose-up position before the release occurred.
The investigation
An examination of the glider at the accident site by the FAA revealed that the spoilers were in the deployed position. Maple leaves were found inside the spoiler wells. The aircraft sustained substantial damage, including impact damage to the mid-span of the right wing and damage to the flight controls consistent with impact forces.
While the canopy attachment pins and surrounding composite material were torn from the fuselage during the crash, the canopy attachment handle and bayonet pins were found to be in proper working order. The damage to the canopy was consistent with the canopy being in a latched position at the moment of impact.