 Late-war additions were limited to the installation of radar, radar detectors and additional AA guns.Although the first few boats were completed at the end of 1939, maintenance problems with the boilers and modifications to the bridge and the normal issues associated with working up boats of a new class, kept them in German waters until mid-1940.Assigned to the 5th Torpedo Boat Flotilla, "T2", "T7" and "T8" began escorting minelayers as they laid a minefield in the North Sea in August.