Don't let Shy Torque see your comment, as he had an even closer call when a glider nearly landed on top of his aircraft during the take off roll.
What about all clear above and behind? Did he not look before lining up?
Here we go again. Yes, of course I looked.
I was departing from a military airfield on an instructional flight in very hazy conditions. As we were holding on the eastern side to line up on runway 31 we were looking into a low winter sun to see circuit traffic. There was another aircraft on the runway which was landing and we were instructed by ATC to expedite line up and wait behind it, which we did. There were also three other aircraft joining, or in the circuit, all of which we saw, including one turning to finals behind us. The glider pilot apparently approached the airfield from the west (directly into sun and head-on to us as we had waited to line up, so presenting a minimum profile in the glare). He cut across the downwind leg and in front of two other aircraft. As we were lined up waiting, he was behind us. As we were rolling at close to 50 kts, a white glider flew directly over us with spoilers out and landed very close ahead. I took control from my student, picked up the starboard wing with the aircraft still on the port mainwheel, and narrowly managed to lift it over the port wing of the glider and yawed us left to prevent a collision.
The glider pilot had a radio in working order but didn't bother to use it. He also had the choice of landing anywhere on the 3000 feet plus circular grass airfield, or in the adjacent fields but chose the duty runway. He could easily have landed alongside us, or flown across the runway and landed beyond on the grass. He apparently then blocked the runway with his glider for some time as he was in no hurry to move it.