Interesting. What is the greatest number of days you’ve been submerged at one time?
My longest time submerged was 74 days on a Lafayette-class boomer, but we snorkeled to run the diesel a few times during the patrol, so the air got replaced then. The rest of the time, it was all scrubbers, burners, and O2 generator for life support. Like someone else posted, we could only take 15 cartons of smokes on a patrol, so the non-smokers would help out by taking 15 cartons and then we would sell them to the smokers towards the end of the patrol.
63 days. But I was on a Fast attack boat. Boomers do 90+