The Submarine I was the pilot on, and repair tech is the Triton Submarines 3300/3. It is a 3-person sub that can go to 1,000 meters or 3,300 feet for 96 hours. The sub has Main and Reserve Oxygen Tanks and Main and Reserve Air tanks. Oxygen is being added to the cabin and there is a CO2 scrubber that removes the CO2. There is no change in cabin pressure all the way to 1,000 meters. There are 6 different ways to surface the sub and only three of them need power. It has communications with the surface, GPS signal, stereo, air conditioning.
I have done over 220 dives as pilot and several of those dives were to 1,000 meters. I did all the repair work (with lots of support from Triton Submarines) on the sub for over 5 years. The sub is a lot of fun and just needs someone that loves it and is willing to give it the time it needs.
Captain Les in the sub