I have added a modded submarine that uses the submarinex simulation class. It works perfectly.
I mean:

• It dives and surfaces. The AI recognices it as a submarine and dives when in combat and stealth mode and surfaces when in non combat mode.

There are some issues that prevent me to continue with this project:

1st: In the cfgdiving there is a lines that controls tha diving rate for the submarinex simulation class, which is 2.0 f.
This is OK for the SDV but not for the bigger submarines.
Could it be possible to add separate diving/surfacing speed for the SDV and bigger subs?

2nd: The main problem is that when a man entity is inside a vehicle that follows the submarinex class simulation tis dies due to lack of air, the cargo, driver, commander and such suffocate.
For the moment, I'm using Men (diver) entities for my tests, but... would it be possible to add a config line so the men inside a "dry" submarine don't suffocate?