Use a gas tank to store high pressure air. I then have this flow to an intermediate tank which only fills if the pressure inside it falls below 1 atm.

Then the intermediate tank connects to your engine or an external air supply (if on the surface.)

You also need to make sure the exhaust goes somewhere. Either store this in another high pressure tank (pack it with a pump) or you can annihilate exhaust by piping it into an air manifold that is not connected to an engine cylinder. (Some might consider this an exploit.)

Exhaust is not a problem anymore, you can use a standard exhaust in 300 meters depth.
The exhaust-tooltip still shows 100 percent. This was not possible before the pressure-update(s).

My underwater-diesel-engine uses the same air like I use....the cabin air.
I have a PID connected to a variable air-tank-valve which set the air-pressure to 1 atm all the time.

Originally posted by superosh:

Exhaust is not a problem anymore, you can use a standard exhaust in 300 meters depth.
The exhaust-tooltip still shows 100 percent. This was not possible before the pressure-update(s).

Intriguing... do we trust that this is deliberate and not an oversight that might get patched out?

Lol, if they patch this out....ofc...without a clou within their "changelogs" as usual, I need to re-design my sub just once more...If I am correct...this would re-design number "7" then. :-)