What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
While in level flight at approximately 4000 feet AGL, the glider began a serious of strong to severe lateral oscillations lasting for 10 to 15 seconds. The pilot stated that his airspeed at the onset was about 80 KTS and during the oscillations the airspeed increased to around 90 KTS. The pilot stated that he had made no significant control inputs and that the level of turbulence at the time was not significant. The pilot slowed the glider and returned to his home base, 89TA. After landing significant damage was observed on the fuselage aft of the cockpit and forward of the tail empannage. The tail cone of the fuselage had several serious longitudinal cracks and a lateral crack on the underside of the tailcone that clearly penetrated through the skin of the tailcone. (This is the second known event of this nature for this make and model of glider).
As the FAA filed it
WHILE IN LEVEL FLIGHT AT APPROXIMATELY 4000 FEET AGL, THE GLIDER BEGAN A SERIOUS OF STRONG TO SEVERE LATERAL OSCILLATIONS LASTING FOR 10 TO 15 SECONDS. THE PILOT STATED THAT HIS AIRSPEED AT THE ONSET WAS ABOUT 80 KTS AND DURING THE OSCILLATIONS THE AIRSPEED INCREASED TO AROUND 90 KTS. THE PILOT STATED THAT HE HAD MADE NO SIGNIFICANT CONTROL INPUTS AND THAT THE LEVEL OF TURBULENCE AT THE TIME WAS NOT SIGNIFICANT. THE PILOT SLOWED THE GLIDER AND RETURNED TO HIS HOME BASE, 89TA. AFTER LANDING SIGNIFICANT DAMAGE WAS OBSERVED ON THE FUSELAGE AFT OF THE COCKPIT AND FORWARD OF THE TAIL EMPANNAGE. THE TAIL CONE OF THE FUSELAGE HAD SEVERAL SERIOUS LONGITUDINAL CRACKS AND A LATERAL CRACK ON THE UNDERSIDE OF THE TAILCONE THAT CLEARLY PENETRATED THROUGH THE SKIN OF THE TAILCONE. (THIS IS THE SECOND KNOWN EVENT OF THIS NATURE FOR THIS MAKE AND MODEL OF GLIDER).
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.