Weapons accidentally dropped by the United States include incidents near Atlantic City, New Jersey (1957), Savannah, Georgia (1958) (see Tybee Bomb), Goldsboro, North Carolina (1961) (see 1961 Goldsboro B-52 crash), off the coast of Okinawa (1965), in the sea near Palomares, Spain (1966, see 1966 Palomares B-52 crash), and near Thule Air Base, Greenland (1968) (see 1968 Thule Air Base B-52 crash). In some of these cases (such as the 1966 Palomares case), the explosive system of the fission weapon discharged, but did not trigger a nuclear chain reaction (safety features prevent this from easily happening), but did disperse hazardous nuclear materials across wide areas, necessitating expensive cleanup endeavors. Several US nuclear weapons, partial weapons, or weapons components are thought to be lost and unrecovered, primarily in aircraft accidents. The 1980 Damascus Titan missile explosion in Damascus, Arkansas, threw a warhead 30 meters from its silo but did not release any radiation.