[KaleunMarco]

Originally Posted by skirich

I started in 1941 with a Tambor class. From what I understand as the war progreses new classes are available. So how do I switch subs classes or is that even possible? Would I need to start a new career?

what jimmbbo says is true.
specifically, you need to be a successful captain in two ways:

• successfully complete your objectives
• sinking tonnage

the game seems to treat a boat upgrade the same as promotion so you need to satisfy those requirements. what exactly are those requirements? no one really knows for sure. a skipper needs at least three or four totally successful missions where his boat has successfully accomplished all of the objectives given and you must sink a good number of ships each mission in order to be promoted or be offered a new boat. how many ships? it depends on their size. each ship has a certain number of points associated with them, based on their tonnage. larger ship=more points. each objective you are given has a certain number of points associated with it also.

that is enough for now. it is time for breakfast and a cup of joe.
good luck and good hunting!