Type 7 U-boat

The Allies were advantageous that the Type XXI U-boat accustomed too backward to see combat. Had it been deployed afore the end of war, it could accept had a adverse appulse on the Battle of the Atlantic.
The Type XXI had abundant avant-garde appearance for its time, including high-capacity batteries that enabled it to abide underwater for days, a automated hull, and a snorkel to recharge the batteries while underwater. With an underwater acceleration of 17 knots, it could in fact outrace a lot of apparent warships.