How did those nukes get on this plane?

The US Air Force is scrambling to explain how it mistakenly flew six nuclear warheads over the United States on August 30th.  We are still in the dark as to how the warheads were loaded on the plane and flown 1,100 miles without anyone noticing this mistake:

Thus far, it’s unclear where, in this elaborate string of checks and protocols, procedures failed.

Ironically, the error comes just six months after the Air Force announced that Minot’s 5th Bomb Wing won two service-wide safety awards during fiscal 2006, including one for its responsible handling of nuclear weapons, the Nuclear Surety Award.

“I just can’t imagine how all of this happened,” said Philip Coyle, a senior adviser on nuclear weapons at the Center for Defense Information. “The procedures are so rigid; this is the last thing that’s supposed to happen.”