[propbeanie]

The real subs did manage to stay down for upwards of 48 hours. They did experience CO2 poisoning, of course, but I do not remember the figures of percentage of atmosphere. It does not take much though. Lethargy is the first sign, as well as a bunch of yawning, as your body tries to bring in more oxygen. For whatever reason, some of the crew tried to smoke a cigarette - nic fit!!! - and their smokes would not stay lit... which was a good thing, because the smoke would have further polluted their atmosphere. Being a former smoker and suffering the effects of my youthful ways the last few years, I wish I would never have started - but that's for a different discussion.

Anyway, you can stay down from first light until after dark in the game, and the effect on your crew is minimal. Much beyond that though, and the game is a bit over-the-top. First signs with the crew, since the 3D world does not change, is a slow response to orders, especially the helm and depth control. You might have to tell the crew several times to come to a given heading, or a set depth. Then they still might "drift" away from that. But that is after a good while of being down. The CO2 meter will light up after maybe six hours? Probably sooner. It does change colors from blue to yellow to red though, to warn you. At yellow is where they really get strange in following "orders". When you hit the red, the crew starts dropping like flies. You won't see them "stagger" at their stations - they just "disappear", and turn "injured" on the crew page. Then they die shortly after. No warning, other than the red icon. Turn on a light switch, and you have it. We had this all timed in FotRSU a few years ago, but have since misplaced the info... I'll see if I can dig that up. Most of the mods don't try to change that from Stock.