I heard a tall story about a DC-8 in Hong Kong that needed to dump (fuel that is!), it was put in a hold, and decended in the hold while dumping.
Apparently it flew through its own vapour and exploded.
Sound like allot of bs to me. But you never know, anyone heard of this one?
ps what would happen if a jet engine ingested fuel vapour, just a bit of a surge I would imagine?
cheers