9. The U.S. Air Force jettisoned two nuclear bombs into the Atlantic Ocean
On July 28, 1957, a USAF C-124 aircraft was transporting three nuclear bombs from Dover Air Force Base, Delaware across the Atlantic Ocean when it experienced a sudden loss of power to both the number one and number two engines. Although maximum power was diverted to the remaining engines, the aircraft remained too heavy to maintain level flight. As a result the decision was taken in the interest of crew safety to lighten the craft and jettison two of the three bombs into Atlantic Ocean.
With their cores removed the first device was ejected at approximately 4,500 feet in altitude, whilst the second followed at about 2,500 feet. It is believed neither weapon detonated, and both are presumed to have been damaged from impact and sunk instantly. Neither the weapons themselves, nor any debris, have ever been recovered, whilst the C-124 returned safely to an airfield near Atlantic City, New Jersey, with the remaining nuclear weapon.