Scapa Flow is easy to inflirtrate.
You need:
1.Patience.
2.More patience.
3.Moonless Night.
4.Early war times .14 October 1939 is fine, 5 days earlier you can find Hood and Nelson
5.Optional Torpedos if you are in the mood to atack.
Sneak in to eastern Scapa passage (Kirk Sound)on surface by night, swim between wrecks. Voila!
DD`s do not see you if you are carefull...
Optional search for Revenge Class BB , shoot salvo of 3 eels and run for your life...
you not survive this if you still be on surface, so you must shoot that salvo underwater,and then swim on silent running close to the coast from there to exit.
Not really like Prien but still fun.
The End
Played on GWX3