The U-boat War in World War Two (Kriegsmarine, 1939-1945) and World War One (Kaiserliche Marine, 1914-1918) and the Allied efforts to counter the threat. Over 40.000 pages on the officers, the boats, technology and the Allied efforts to counter the U-boat threat.
Why Submarine Deck Guns were Eliminated on German WWII U-boats
Why were the guns on submarines still usable after being underwater? Wouldn't the guns rust or jam being exposed to sea water? - Quora
Kriegsmarine U-Boats 1939-45: Essential Submarine Identification
HobbyBoss manufactures static plastic model kits and the company has became an established and very well-regarded brand after many years of hard work.
HobbyBoss 83504 WWII German Type VIIB U-Boat 1/350 Scale Plastic Model Kit
Kriegsmarine U-boats 1939–45 (1) (New Vanguard): Williamson
U-boat Deck guns - Technical pages - German U-boats of WWII
Academy 1/150th Scale German Navy U-boat IX-B
HobbyBoss 83504 WWII German Type VIIB U-Boat 1/350 Scale Plastic
U boat hi-res stock photography and images - Page 3 - Alamy
Submarine Photo Index
U-boat, Military Wiki
Schroder: Kaisers U-boats
Type VII U-boat > WW2 Weapons
Why were the guns on submarines still usable after being underwater? Wouldn't the guns rust or jam being exposed to sea water? - Quora
U boat hi-res stock photography and images - Page 3 - Alamy