The Marder or “Pine Marten” was not a mature U-Boat like the Molch or Seehund. This midget submarine was an advanced design of the Neger submarine. These type of submarines were manned torpedo’s. It was a 5,5 ton vessel with a Plexiglas cockpit with a 360 view. It is about 8 meters long and halve a meter wide. While the Neger could not fully submerge the Marder could reach a depth of 30 meters although it could not stay submerged for a long period. The Marder lacked a periscope. The pilot sat in the front of under the Plexiglas dome, beside the excellent view it had a compass inside the dome for navigation. The pilot wore a rubber suit and used an oxygen mask to avoid carbon dioxide poisoning.
Underneath the vessel was one G7e torpedo attached, after firing the torpedo the pilot could come back to port with the top compartment. Submerged it had a speed of almost 3 km/h, on the surface it could reach 3,5 km/h. Its operational range was about 55 kilometers, due to its limited reach and diving depth it only saw action in the Mediterranean and the English Channel.
The Marder entered service in 1944. It fist action was on the night of 2 till 3 Augustus in 1944. With a fleet of 58 manned torpedo’s the Kriegsmarine attacked the invasion shipping o f Coureulles-sur-Mer, fleet had a mixed built up of Negers and Marders. Only 17 of the 58 returned to port, the others destroyed by a counterattack from the Allied forces. The manned torpedo’s sank a liberty ship, en mine sweeper and a destroyer and damaged a cruiser and transport ship on this attack.
Although the Marders had limited success the pilots considered them as suicide vessels. They often took Pervitin, a powerfull amphetamine before a mission.