What was a group of german u-boats that operate together to attack allied shipping in the atlantic called?

 A group of German U-boats that operated together to attack Allied shipping in the Atlantic during World War II was known as a "Wolfpack" (German: "Rudeltaktik"). This tactic involved groups of submarines working together to overwhelm the defensive capabilities of merchant convoys and the escorts that accompanied them. The idea was that a coordinated attack by several submarines would increase the effectiveness and success rate of their mission, causing significant disruption to Allied shipping and supply lines.

Extra: The concept of Wolfpack tactics was developed by the German navy, the Kriegsmarine, to maximize the strategic impact of their submarine fleet, known as U-boats. The Wolfpack tactic emerged as a response to the increasingly effective convoy system implemented by the Allies, where multiple merchant ships would sail together, escorted by warships equipped to deal with submarine threats. By hunting in packs, U-boats could use their numbers to penetrate the escorts' defenses and cause chaos, making it easier to sink multiple ships.

Admiral Karl Dönitz, the commander of the German U-boat fleet, was a key proponent of the Wolfpack strategy. The U-boats would spread out across the expected path of an Allied convoy, and once a U-boat spotted the ships, it would shadow the convoy and call in other U-boats using radio communications. When enough U-boats had gathered, often at night, they would launch a coordinated attack.

The effectiveness of Wolfpacks varied throughout the war, with successes peaking during the early years, particularly in the Atlantic. However, as the Allies developed better anti-submarine warfare tactics, including improved sonar detection, airborne patrols, and breaking German communication codes, the success of Wolfpacks declined, and the strategy became increasingly risky for the U-boats.