In the early 1930s Hellmuth Walter had designed a small, high-speed submarine with a streamlined form propelled by high-test peroxide (HTP) and in 1939 he was awarded a contract to build an experimental vessel, the 80 ton V-80, which achieved an underwater speed of 28.1 knots (52.0 km/h; 32.3 mph) during trials in 1940. In November 1940 Admirals Erich Raeder and Werner Fuchs (head of the Kriegsmarine's Construction Office) witnessed a demonstration of the V-80; Raeder was impressed, but Fuchs was slow to approve further tests.