These ships could also function as flagships of torpedo boat flotillas. It was transferred to Motor Torpedo Boat Squadron Two on 7 May 1942. Most of the boats were initially assigned to the 3rd Torpedo Boat Half Flotilla. Hartenstein took command of torpedo boat on 20 November 1938. She was later renamed "Torpedo Boat No. 1". Protection against torpedo boat attacks was provided by twenty QF 12-pounder 12 cwt guns. Most of the boats were initially assigned to the 4th Torpedo Boat Half Flotilla. She was supported in this operation by the destroyer "Z25" and torpedo boat . Designed as a fast torpedo boat, the had a top speed over . U.S. Navy PT boats were organized into motor torpedo boat squadrons (MTBRONs). Despite this, Motor Torpedo Boat Squadron Three continued to patrol. Until 1962 this was classified as a large torpedo boat. Hipper then took part in torpedo boat instruction from January to February 1893. Only two survivors were rescued by the German torpedo boat . It accounted for one Italian submarine, nine merchant vessels and one motor torpedo boat (MTB).