Who had the best submarines in wwII?

[VONHARRIS]

Originally Posted by Schwieger

I'd take a B-1/I-15 sub over the 7c or Trench, Gato or Balao... seaplane could really help to spot those targets not to mention it was as fast as the American boats

On the other hand the seaplane would have been spotted by the targets and that means destroyers hunting you.

I believe the Germans had the advantage in submarine warfare (both in weapons and tactics) at the start of WWII and lost it to the Allies ASW technology.

If the XXI type was put to service earlier then they might had a chance to fight back.

IMO the XXI and her little sister XXIII were the best subs of WWII.