Determined enemy: The U-47 Scapa Flow Raid

Sometimes we assume that our protective measures are adequate, when, in fact they just haven't been tested by a determined foe. Such was the case of the the German U-boat U-47, which snuck its way through the defenses of the British Home Fleet at Scapa Flow and sank the Royal Oak. It's a cautionary tale and an exciting sea story, too. Start with the introduction and then click on "Scapa Flow" on the left menu.