I've only heard of two incidents. One was investigated by the NTSB and (IMO) both the pilots of the manned aircraft and the RC aircraft were partially at fault.

I've only heard of two incidents. One was investigated by the NTSB and (IMO) both the pilots of the manned aircraft and the RC aircraft were partially at fault. NTSB report blamed the RC pilot. No injuries but the manned aircraft was damaged, and the RC aircraft destroyed. This occurred at low-level ( < 50 ft) over the runway. The second was that the small military UAV was blown off course due to changing winds, while a jet was doing a ground power run. The RC aircraft crashed short, with some debris hitting the aircraft wing. UAV operations were authorized, although the Tower controller and Ground (Movement) controller didn't foresee the hazard.