Brummer was ordered under the contract name C from A.G. Vulcan, which held turbines originally intended for Russia. Germany had the machinery but still needed a hull, armament, and operational arrangement. An iterative line of successors to the Nautilus class could have settled those questions before wartime pressure. Instead, designers had to build the ship around an opportunity created by seized machinery.
Chapter · 20:22-21:31
From seized turbines to a wartime design
Brummer's hurried design process shows how seized Russian-order turbines created an opportunity that Germany had failed to prepare for before the war.