What happened
On June 6, 2011, at approximately 11:00 UTC, a TST-10 M Atlas ultralight glider (registration OK-A707) was performing a thermal flight from Ústí nad Labem (LKUL) to Chomutov (LKCH). During the approach to runway 14 at Chomutov, the pilot misjudged the aircraft's altitude and distance from the runway threshold.
As the aircraft descended, the left wing struck tall grass located approximately 52 meters before the start of the runway. The impact caused the glider to rotate to the left, resulting in the left wing spar breaking. The aircraft subsequently overturned onto its back, with the cockpit making contact with the ground. The pilot, who was the sole occupant, sustained no injuries.
The investigation
The ÚZPLN investigation focused on the sequence of events leading to the impact and the condition of the aircraft. Investigators examined the wreckage and found no evidence of mechanical failure or issues within the flight control system. The pilot's medical certification and flight experience—totaling over 544 hours, with over 300 hours specifically on the TST-10 M Atlas—were found to be sufficient for VFR operations. Additionally, the aircraft's technical certificate was valid, and no evidence of structural defects prior to the accident was identified.
Findings
The investigation concluded that the accident was caused by a short landing distance combined with the presence of tall grass at the landing site. The pilot's misjudgment of the aircraft's height and the impact with the vegetation led to the loss of control and subsequent structural failure of the wing.