15 kts was the norm to get to patrol areas. Normally about 8 days from Midway to Japan shipping. They would run on two engines and that would save fuel. Sometimes the bilges were filled with fuel to add range. Once on stations the better part of the day was submerged patrol to avoid aircraft. Night time surface for patrol and battery recharge. It is unfortunate the game fuel is a bugger and we need to travel at around 9 kts. Later on if you are using RSRD there are refits ships you can use to fuel.
Charts? The charts the skippers had were found at the local library and did not have depth. Some skippers had just old maps to work with or a lame National Geographic map that was outdated. Charts showing depth around islands were not available. Anyway, if you are in TC the game will stop you if you are about to ground....most times anyway!
