[djmcmath]

Sorry, didn't mean to confuse anyone with facts or technical details. (blushes) It's just that there are so few things I know anything about, when one comes up that I can contribute usefully with ...

Kach -- torpedo doors make a lot of noise when they open. Clankety-clankety-clank, audible from really huge distances. You don't so much "see" the doors open as hear them -- just like anything underwater. Collisions happen when submarines are trying to be really super-quiet (and succeeding). They get closer and closer trying to get close enough to hear something, then they go "bump" in the night. Sort of.

Marc -- oorah. Always good to find another dolphin-wearer. I can hardly wait to get back to a boat. Are you still in?