20230722017809A

Pilot stated: finishing up a cross country glider flight. On final glide from wharton to TE-71. I was not in a hurry and had plenty of altitude for final glide. Set up glide at 79 knots, in the green, for this aircraft and began glide and decent from 6000 feet. At 4000 feet straight and level I experienced a severe vibration and shaking of the aircraft. There was no bird strike I saw and no severe turbulance. I thought to myself I am going to slow for a elevator flutter but I decided to pull full spoilers and slow down. At 60 knots the shaking stopped. I tried all the controls and they worked. I slowly increased speed and the vibration returned so I pulled spoilers again and the violent shaking stopped again. At this point, I had to make a decision to either blow the canopy and bail out or continue. I was only about 2 miles from the field and stable so I decided I would stablilize the ship and not overcontrol it and glide in. I called the field and anounced I had an emergency with my plane and I was making a straight in to landing. I called to see if any gliders were around and could check me out but no one was close enought. I landed and rolled to a stop. Got out and found out then I had structure damage to the tail boom.

I inspected the glider and found substantial damage to the carbon fiber structure of the tailboom encompassing 360 degrees around the boom in 2 differant areas separated by approx 12 inches.