Aircraft operating between Britain and Allied-held Norwegian bases can maintain surveillance across the North Sea approaches. A sortie by Bismarck and a Scharnhorst-class partner is therefore more likely to be detected early and met by a complete fleet with carriers, battleships, cruisers, and destroyers. The same geography complicates the initial transit of German U-boats during the period when the submarine arm is still building strength. Control of airfields on both sides of the sea turns detection into a sustained barrier rather than an occasional patrol.
Notable Point · 51:32-53:18
Norwegian bases tighten the Atlantic barrier
Allied airfields in Norway enable denser maritime patrols, making German submarines and surface raiders easier to detect as they enter the Atlantic.