Ares has the latest on the B-2 crash investigation, with video of said crash! According to this AvWeek summary, the cause was moisture in some of the wing sensors of the plane. Crews long ago learned a quick and simple fix, but nobody bothered to write it down. Considering the consequence was the loss of a very expensive bit of weaponry, something tells me there's a whole chain of noncom maintenance people who are in one helluva lot of trouble.