Here are links to two consecutive videos on a lost atomic bomb. By the way, I got a lot of buffering pauses; that could just be me.
Part 1 (2:30): http://www.wral.com/lifestyles/travel/video/5050531/
Part 2 (2:21): http://www.wral.com/lifestyles/travel/video/5059120/
Briefly, a B-52 crashed in 1961 with two atomic bombs on board. One was found. The other one never has been completely recovered. I’d heard everything on the video before except I don’t remember hearing the size of the bombs (megaton range) or how long they looked for the missing bomb. Oh, my dad said that he and one of his cousins went to the crash site to go looking around.