The shutter animations took me all morning and I still havnt got a working solution, I shoud've spent it doing something more productive oh well.
Dont think I'll get much/anything else done today and the weekend will proibably be slow but I found some great deatils on hte Balao class
http://maritime.org/doc/fleetsub/chap4.htm#4A
regarding the tanks and how much water they hold plus their locations so I'm going to simulate their locations exactly and see how she handles as well as make up a formula/do the math for pumping water/air into/out of the tanks for that many many tons of water. Should be easy knowing the weight of water per cubic cm