High Quality Content by WIKIPEDIA articles! The Seehund (German: "seal"), also known as Type XXVII, was a successful series of German midget submarines created during World War II. Designed in 1944, and operated by two man crews, the submarines were used by the Kriegsmarine during the closing months of the war, sinking 9 merchant vessels and damaging an additional 3, with 35 losses mostly attributed to bad weather.