 Complete the following phrase:  Z21 Wilhelm Heidkamp was one of six Type 1936 destroyers built for the Kriegsmarine German Navy in the late 1930s. Completed a few months before the start of World War II in September 1939, the ship served as a flagship throughout her career. She briefly patrolled the Skagerrak where she inspected neutral shipping for contraband goods. Z21 Wilhelm Heidkamp later helped to laid four offensive minefields off the English coast that claimed two British destroyers, 2 fishing trawlers, and twenty-seven merchant ships. During 