Yup, yup, yup. Everything human-usable is going to be in a pressure hull, because a hundred meters of depth is going to absolutely wreck more or less everything

Yup, yup, yup. Everything human-usable is going to be in a pressure hull, because a hundred meters of depth is going to absolutely wreck more or less everything. Especially seals. Hangar doors give me nightmares. They might pressurize the crew spaces, a little, but it's really not possible to crank up the air pressure meaningfully for any duration, too hard on the body, and totally lethal if they come up too fast. On that subject google up "saturation diving" for some frickin' horrors. Those dudes make bank, but whew, talk about earning it.