how can you get hull repaired?

you pull into port for refitting and rearming but all you get is minor repairs, fuel, and ammo.

i realize ship repairs take time but if i come into port needing serious repair i wont turn around and go back out on patrol when a bird taking a dump on me will sink me lol.

if my ship is no longer seaworthy then i should be able to make the repairs if i spend enough time in port but no repairs are even attempted, why?

is there a way to reset the hull damage when you refit?