This was mostly fixed in the VIIB which had additional 33 tons of fuel in external saddle tanks which gave them additional range of about 2500nm at 10 knots. They were also considerably more powerful and slightly faster than the VIIA was. This gave them even more agility. The only major armament difference was that 3 additional torpedoes could be stored for a total of 14. The next development of these series was the mass produced type VIIC with several improvements.
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