Crash Dive Question

Originally Posted by Sailor Steve

Another drawback, as I said, is that there is no way you're going to open up everything, diving as quickly as possible, and then pull out at periscope depth, or even thirty meters. As to your <shudder>, did they ever 'pull the plug' without a green christmas tree?

I agree! I don't see how you can set everything for a max-rate of dive and expect to abort that half-way through and level off at periscope depth, or even 30 meters for that matter. That's a lot of inertia driving you at that point.

I've never read of an account where a dive was started intentionally without a properly functioning green board. I'm almost positive that that's considered 'against the Book'. But I have to wonder if that didn't happen in wartime a lot. Shaving seconds here and there might be risky, but so is being a sitting duck half-submerged as ashcans rain down around your ears.

I've seen several war footage videos on-line (mostly on youtube). Mostly they've been propaganda ones. From the films it does seem as if they're already setting dive planes and flooding tanks even while the watch crew is still clearing the bridge. As an open conning tower hatch would definitely red-light the board, it appears as if they are starting to dive without a full green board.

With regards to SHIII, the game certainly lets you start a dive without full green. There's no way the diesels should run as long as the game has them run. The main induction (the air intake that ventilated the submarine on the surface, and in particular, supplied external air to the diesel engines) is one of the biggest --and potentially fatal-- openings through the pressure hull, and diving with it remaining even partially open is deadly.

The S-5 sank due to the main induction being left open. That sinking was also the driving force to design and implement automated indicator boards (the Christmas tree).*

I'll keep researching. :hmm:

*ref: http://www.chinfo.navy.mil/NAVPALIB/...ssue_23/s5.htm

[Steeltrap]

Originally Posted by Segwin

How did you do that?

It's in the .cfg files. There is a folder for each u-boat type. Each contains a line "crash dive = x". I'd give the specific folder/sub-folders but I'm at work, not home.

Just change that to whatever you want and that's where it levels. NYGM 2.2 set it to 20m (stock is set at 70m). I believe that was to allow you to dive quickly and then not have the "interrupt" problem. You end up levelling at whatever depth is there. Diving after that is done by selecting the depth per usual or just pressing "D".

As for diving before a green board, Cremer says he usually opened the main vents himself after dropping down from the bridge. On some occasions he says there was already water starting to wash around the base of the tower, but I'm not sure how that would happen without the vents being opened first (not a submariner, so I don't know.....). He also tells a story of how one colleague ended up diving so quickly that he had his cap knocked off in the scramble down the hatch, didn't have time to grab it, so the boat dived and left his cap floating on the surface! Quite an amusing scene after the fact, but probably a bit more nerve wracking at the time.

Originally Posted by Steeltrap

. . . On some occasions he says there was already water starting to wash around the base of the tower, but I'm not sure how that would happen without the vents being opened first (not a submariner, so I don't know.....). . .

Perhaps the dive planes were already set to dive? That would begin forcing the boat under even with the tanks empty.