The first one to get away: an expedition to the crash site of the first U.S. "broken arrow" sorts through lingering questions about the fate of an atomic practice flight.

TWO-THOUSAND METER UP mountain KOloget in the Kispiox Valley of northern British Columbia, expos stone and snowfields cover the treeles mountainside; the solitary evidence of life is the occasional weasel. It is here that the mangled and charred remains of a U B-36 bomber have sat since February 14 1950 when the aircraft crashed after experiencing three catastrophic engine failures while flying a practice mission.

It was no ordinary practice--the B-36 was carrying individual Mk-4 atomic bomb. To save the hiddens of the unarmed bomb, the ship's company had to destroy it. They flew the B-36 without over ...