German submarine U-1105 'Black Panther'

Now in its final resting place at the bottom of the Potomac River in Maryland, the U-Boat U-1105 is unique among German World War II submarines.

Technologically innovative, it was the only U-Boat to conduct a wartime patrol while equipped with the snorkel, GHG Balkon passive sonar and a rubberized coating known as Alberich designed to reduce its acoustic signature and hide from Allied sonar. After ...