Cika wannan jumla: A 1941, an fara gina sansanin jirgin ruwan karkashin ruwa na DORA 1 a Trondheim. Shekaru biyu bayan haka, a watan Yunin 1943, an mika shi ga kwamandan jirgin ruwa, "Korvettenkapitän" (daga baya "Fregattenkapitän") Rolf Rüggeberg. Jirgin ruwa na 13 na jirgin ruwa na jirgin ruwa ya kasance na gaba, kuma jimlar 55 Type VIIC da &lt; a href="German%20Type%20VII%20submarine%23Type%20VIIC.2F41"&gt; VIIC/41&lt;/a&gt; ya yi aiki tare da shi har zuwa
karshen yakin a watan Mayu 1945.