list of useable subs in game?

[MajorTOM_WLFPAK1]

is there a list of subs u get to use in game. other than the ones at the start of a carr. .

im asking becouse i started out in a 1941 salmon class sub in java.got a promotion and new sub in early 42 and sent to pearl harbor and was given a 41 modle gato class .when i got a promotion and new sub in early 1943 i was given a 1943 balao class sub and sent to brisbane. i exspected to get a new modle of the class i started with , witch would make sence .

unless you wanted a new sub class then it should have been the class you had. is there any way to have diffrent modles of the same
class?

what im asking is when u get a new sub is it always a diffrent class ? why dont u get a new modle in the same class u start a game with. say u start in 42 and get a gato class sub and then in 43 u get a new sub . why not get a new modle of the class sub u have or get a chance to go to a new class of sub and get the balao class . this to me would make sence. say u dont take the new sub and stay with the one u have do u get to add the the diffrent thing from the next modle say a new conning tower ?