A “Broken Arrow” is defined as an unexpected event involving nuclear weapons that results in the accidental launching, firing, detonating, theft or loss of the weapon.
A US B-36 bomber experienced mechanical difficulties over the Pacific Ocean, resulting in the need to jettison the nuclear bomb on board before it crashed on Vancouver Island. No nuclear explosion was set off. The US military uses the term “Broken Arrow” to refer to an accident that involves nuclear weapons or nuclear weapons components, but does not create the risk of nuclear war.
Further materials:
https://www.atomicarchive.com/almanac/broken-arrows/index.html
