A detailed study of history and marine archaeology of a U-boat.

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. It was the only U-Boat to conduct a wartime patrol while equipped with three technological innovations that revolutionized submarine warfare in the post-war world.

These were- the snorkel (air-mast) that allowed the U-Boat to remain submerged indefinitely; the GHG Balkon passive sonar mounted forward of the keel that increased listening range by 70%; and a rubberized coating known as Alberich designed to reduce its acoustic signature and hide from Allied sonar.

This is the first book to analyse the U-1105 combat record using primary documents in order to evaluate the effectiveness of its late war technologies, document its extensive postwar testing and detail all the features still present on the wreck site today. The U-1105 remains the only U-Boat in North America that someone can dive and still see remnants of its snorkel trunking and Alberich coating.

The book gives details of the U-Boat's construction, training, first and only combat patrol, and extensive postwar testing and evaluation by both the Royal and US Navies. It contains c. 50 images of U-1105 from wartime, postwar testing and of its condition at the bottom of the Potomac. Many of the images are new and previously unpublished anywhere.