Print this page MADRID - After 55 years, a group of U.S. veterans may be closer to securing disability benefits denied to them following a Cold War-era accident they say has now left them with serious medical conditions. The accident involved the collision of two U.S. aircraft over Palomares in southern Spain and the ensuing discharge of radioactive materials from hydrogen bombs. On January 17, 1966, a B-52 left a U.S. base in North Carolina on an airborne alert mission called Operation Chrome Dome. The flight path took the aircraft east across the Atlantic Ocean and Mediterranean Sea toward the eastern borders of the Soviet Union. The lengthy mission required two refueling flights over Spain.