Incident Details
On 28 September 2014 at 09:54 LMT, a glider (SZD-9bis Bocian 1E) was conducting a training flight at Kruszyn airport near Włocławek (EPWK). The flight was part of the SPL training program, exercise SPL/IV-3 'Landing with tailwind.' The aircraft was crewed by a 71-year-old instructor-pilot and a 43-year-old student-pilot. The takeoff method was aerotow. After a correct touchdown with tailwind, during the final stage of the landing roll, the screw securing the main landing gear axle attachment failed. The airport surface, crew actions, and weather conditions did not influence the occurrence.
Cause
The cause of the incident was the breakage of the screw securing the axle of the main landing gear wheel to the landing gear arm. The reason for the screw failure was not established; no fatigue marks or corrosion were found on the broken screw.
Contributing Circumstances
Circumstances that may have contributed include operation of the aircraft in training flights, which involved a high number of landings, and the touchdown with higher ground speed due to the tailwind landing.
Aftermath
The incident was discussed with the flying personnel. They were reminded to exercise particular caution when performing tailwind landings. No safety recommendations were issued by the investigation commission.