[tedhealy]

Silent Hunter 4 simulates the career of a captain according to real practices of the US Submarine Force of the period. Depending on your performance you can expect your career to last between 5 and 8 patrols. Of course, real silly results such as sinking your own capital ships will lead to a quick and timely termination of your command.
The time spent in base between patrols, it will generally be in the range of 2 or 3 weeks:
a. Returning home with a damaged submarine may lead to longer refit times (and time spent in base) due to repairs that need to be performed.
b. Occasionally your submarine may undergo a longer refit which will bring upgrades but take long to complete, thus lengthening the time spent in base.
e. If you are selected to command another submarine, training with the new crew will delay the next patrol by at least a few weeks.