German submarine U-1105 'Black Panther': The naval archaeology of a U-boat

By Aaron Stephan Hamilton

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 the end of World War II, it was the subject of instense testing and evaluation by the Allies, before finally being sunk to the bottom of the Potomac River.

This highly illustrated book uses many new and previously unpublished images to tell the full story of this remarkable U-Boat, evaluating the effectiveness of its late war technologies, document its extensive postwar testing and detail all the features still present on the wreck site today.

• Language: English
• Publisher: Bloomsbury Publishing
• Release date: Jun 27, 2019
• ISBN: 9781472835802

Book preview

PREFACE

My interest in the German U-boat that rests in the mud off Piney Point, Maryland was driven by a desire to better understand the late-war German technology with which it was outfitted, and how this technology was employed when it conducted its first and only wartime patrol. When maritime archeologists conducted the first survey on U-1105 in the early 1990s, their understanding of this U-boat’s unique features and wartime operational impact was based upon the available published historic record of that time, as well as what could be derived from the Naval Historical Center (now Naval History and Heritage Command) in Washington, DC, and the private German veterans institution known as the U-boat Archive in Cuxhaven, Germany. All of this research, however, was limited. The historic picture that was produced of U-1105 at that time was certainly fascinating, but left many questions unanswered. Key features on the U-boat went undocumented. Aspects of its wartime history that appeared conflicted were not resolved. In the introduction to U-1105’s 1993 site survey for the Maryland Historical Society the main authors and lead maritime archeologists for the project, Michael Pohuski and Donald Shomette, wrote that: Obviously additional research is necessary… Indeed it was.

Like all shipwreck sites, measurements can be made, photographs taken, and drawings rendered. Yet, no matter how many dives are made, the shipwreck’s complete history can never be divined through the interpretation of what rests on the sea floor, or in this case, the river bed. Maritime archeology can be used to answer lingering questions of history, and historical research can provide answers to questions raised during such surveys. However, maritime archeology and thorough archival research are forever critically linked. In this case, neither discipline alone could provide all the answers necessary to complete the history of U-1105.

My first dive on the U-1105, also known as the Black Panther, set in motion a nearly six-year research effort that spanned two continents and nearly a dozen archives, libraries, and private collections. That effort resulted in my forthcoming study Total Undersea War: The Evolutionary Role of the Snorkel in Dönitz’s U-Boat Fleet, 1944-1945. What I came to learn in the course of this research is that U-1105 is not just unique, but one of a kind: it was the only U-boat ever to conduct a wartime patrol equipped with three distinct and transformative late-war technologies that ushered in the evolution of modern submarine warfare. This fact has gone unrecognized to this day.

It was clear to me after my very first dive on U-1105 that this U-boat required its own extensive historical treatment given its unique place in the history of World War II, postwar testing, and the local history of Chesapeake Bay. As my dive partner Fred Engle likes to say: It’s a U-boat in our own backyard. As true as this is, unfortunately, no individual work of history has been published on U-1105 to date. The few published articles and online references to U-1105 are incomplete or inaccurate. May this work serve as a comprehensive historical and maritime archeological guide to one of the most unique submarines of World War II.

Aaron S. Hamilton

Fairfax, Virginia

May 2018

INTRODUCTION

I first became aware of U-1105 in 1995 while a graduate student of military history at Old Dominion University. At the time I was working on a Master’s degree focused on how the German armed forces in Western Europe managed to recover after their disastrous defeat in France during the summer of 1944 and continue to resist for nearly 12 more months. While my research did not focus on aspects of the German Navy, I knew anecdotally that U-boats operated in European coastal waters with ferocity long after they were driven from the North Atlantic.

It was reported in the news at that time of the discovery of a lost U-boat known as the Black Panther had occurred. Its unusual name was derived from a late-war secret rubber coating designed to reduce its sonar signature underwater. Its historic allure only increased as news reports cited its seemingly mysterious disposal by the US Navy in the Potomac River. Being a certified scuba diver, I longed to get wet and see U-1105 for myself, going so far as to call the then director of the Maryland Historical Trust and enjoying a lengthy conversation about U-1105 and how best to dive the site. However, it took me almost 20 years to finally do it and touch down upon its silted conning tower off Piney Point, Maryland.

My first dive on U-1105 was extremely memorable. It took place on a Saturday in October 2013 right after a late-season storm had blown through. My dive partner was Tom Edwards. No person has dived U-1105 more than Tom Edwards. He knows every inch of the dive site and served as a volunteer who placed and recovered the U-1105 floating marker buoy for years for the Maryland Historical Trust. We left the long boat dock in a nearly 60-year-old converted Chesapeake crab boat in the dark, as the storm’s lingering wind whipped the diminishing rain against us and our gear.

As we motored out to the dive site around Piney Point, Tom gave me the obligatory safety brief. The dive site would be dark, almost as black as night. If you lost sight of the U-boat you might find yourself disoriented in the inky blackness of the Potomac River. If you did, you would have to launch a surface marker buoy and ascend to the surface on your own, which could be dangerous as this was a high-traffic area of the river. If you surfaced on your own, you might have to drift with the current until the dive boat came and recovered you. The best was yet to come. Tom produced two pictures of bull sharks. Yes, bull sharks. One was caught in the Potomac River just above the U-1105 dive site and the other just below. They were among the largest bull sharks caught in the river to date. Bull sharks, being able to live in salt and fresh water, are common visitors to the Chesapeake Bay in the late summer and early fall. I’ll never forget Tom’s words: They’ll see you before you see them.

By the time we made it out to the site we had noted that the dive ball that allowed you to descend to the conning tower was gone – possibly blown away by the recent storm. Tom decided he was going to dive to the bottom of the Maritime Preserve’s main marker buoy chain then use a compass to make his way to the U-boat and send up a surface marker buoy tied to the wreck that I could then use as a dive guide. He rolled over the side of the boat and into the murky green swells. The rain had stopped by now, but the wind was still gusty underneath the gray sky.

Perhaps ten minutes later he surfaced off the starboard side of the dive boat and began to swim back to us running a thin orange line. When he made it back to the boat he informed me that the original dive ball was there, just encrusted enough with marine growth that the added weight forced it below the surface.

He had tied a line to it and told me to jump in, follow the line to the dive ball, and wait for him at 6m (20ft) below the surface, where he would join me shortly. Once he arrived on the dive line, we would descend to the conning tower of U-1105 together.

I followed his instructions and soon found myself at what can only be described as a stark transition between a deep murky green and inky blackness. Even the line that held the dive ball in place showed no growth below this point, as the lack of light prevented the required photosynthesis. There I waited, staring at the line below as it disappeared into blackness, gently bobbing with the swells.

Minutes ticked by as my air supply diminished. I looked up the line and saw no Tom. I looked down the line again into the inky blackness. I knew I should have stuck around for Tom, but I had waited a long time for this dive. I made the decision to descend down the line on my own and rendezvous with Tom below.

Hand over hand I pulled myself down, armed with only a single canister light mounted to my wrist, its beam barely penetrating the blackness. After a few minutes that seemed much longer, I checked my depth gauge; I was at 18m (60ft) and I knew I was getting close. Then I felt the bump along my left foot. I froze, Tom’s words echoing in my ears: They’ll see you before you see them. I slowly moved my left foot in the hope that I would again bump something stationary, because if I didn’t, I knew instinctively I was not alone. Then I felt it.

My foot had struck cold steel of the port-side conning tower. I breathed a sigh of relief and slowly began to rotate my light around through the blackness as U-1105 finally began to emerge from my imagination into reality. Although the majority of the U-boat is unfortunately submerged under river mud and inaccessible, you can still swim along the conning tower and see its rubber coating and the external snorkel trunking.

The U-1105 Black Panther, a Type VIIC German U-boat, is the only diveable U-boat in the world equipped with three unique late-war German technologies designed to transform what was essentially a submersible at the start of the war into a true submarine and enter a Total Undersea War, as it was called by U-boat command. The most critical technology that U-1105 was equipped with was an airmast device known as the snorkel that allowed a U-boat to obtain fresh air while remaining submerged. Subordinate to that new innovation was an antiacoustic coating known as Alberich that reduced the effectives of Allied sonar, and a new passive sonar array design called the GHG Balkon that gave a submerged U-boat a significant advantage in detecting Allied vessels. In fact, U-1105 was the only U-boat in the entire fleet to conduct an operational patrol while equipped with all three late-war innovations.

After the war, U-1105 was tested extensively by the Royal Navy; in fact, it was tested more so than any other surrendered U-boat. While most might believe its antiacoustic coating was at the heart of this testing, they would be wrong to draw that conclusion. Its snorkel took center stage. The main testing against Alberich occurred in a lab to confirm whether or not it had antiradar or antiacoustic properties. Alberich’s operational relevance was slow to be implemented among Western Allied navies in the postwar period. Not even the US Navy conducted a single operational evaluation of any of U-1105’s late-war technology. They simply treated it as a derelict test subject.

What follows is this U-boat’s fascinating story of its commissioned wartime service in the German Navy; its extensive testing as a Royal Navy submarine; its brief focus as a war prize sought after by the Soviets; its harrowing crossing of the North Atlantic – the