Final Rank

[Raptor1]

Anyone know how to get this rank, exactly (Think it was Kapitan zur See)

[Toltol]

I think the medals symbolize how good you finished that particular patrol and in order to achieve the highest rank possible, you have to finish at least three with the highest possible rating. I'm not sure though which medal represents the best possible rating, but I'm pretty sure it's the Knight's Cross.