Raider (piracy)

Merchant raiders are armed commerce raiding ships that disguise themselves as non-combatant merchant vessels.

Germany used several merchant raiders early in World War I (1914–1918), and again early in World War II (1939–1945). The most famous captain of a German merchant raider, Felix von Luckner, used the sailing ship SMS Seeadler for his voyage (1916–1917). The Germans used a sailing ship at this stage of the war because coal-fired ships had limited access to fuel outside of territories held by the Central Powers due to the Allied Blockade of Germany.

Germany sent out two waves of six surface raiders each during World War II. Most of these vessels were in the 8,000–10,000 long tons (8,100–10,200 t) range. Many of these vessels had originally been refrigerator ships, used to transport fresh food from the tropics. These vessels were faster than regular merchant vessels, which was important for a warship. They were armed with six 15cm (5.9 inch) naval guns, some smaller guns, torpedoes, reconnaissance seaplanes and some were equipped for minelaying. Several captains demonstrated great creativity in disguising their vessels to masquerade as allied or as neutral merchants. Kormoran sank the Australian cruiser Sydney in one of the most well-known episodes involving merchant raiders during World War II.

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