The Shipwreck Hunter

by David L. Mearns

  The Bay of Biscay has a reputation amongst sailors for the fierce stormy weather that can turn it in an instant into a cauldron of treacherous wind-whipped waves. I had been through such a storm years before during a search for a different shipwreck, so I knew it could happen at any time of the year and had made a contingency in my schedule for just such an event. Unfortunately my bad luck was repeating itself, as the Northern Horizon was slammed by a Force 10 storm (winds 45–50 knots, six-metre seas) as soon as we arrived at Bismarck’s location. Standing down for bad weather is never good, but it is especially painful at the start of a project because it doesn’t allow the crew, especially those who haven’t been to sea before, to settle in and get accustomed to the movements and routines of the ship. No meaningful work could be done and the only form of amusement was watching the documentary film team run to the rails to be seasick, or visiting the bridge to watch the largest waves crash over the bow. Really bad Biscay storms have been known to last a week, but this time the blow was short and sharp and only two days were lost.

  To make up the time, I really needed to find Bismarck’s wreck as quickly as possible. My problem, however, was that she had sunk in seriously deep water, over 4,600 metres, which meant everything would take longer than usual. My promise to C4 was that I’d find the wreck in no more than four search lines, but since every line and turn in this depth of water could take up to fifteen hours, I was aiming to find it on the very first line. I’d hired my old company, Oceaneering, as the search and ROV contractor for the project, which meant I was reunited with the Ocean Explorer 6000 sonar search system and some of the guys I used to go to sea with. As nice as it was to be with old mates, I was most pleased to have the Ocean Explorer at my side again. I knew the system so well, and the best way to maximize its ability to search huge expanses of sea floor at a rapid rate. Finding shipwrecks was what the Ocean Explorer was built to do, and since its first success with Lucona nearly ten years before, I had personally used the system to find fourteen shipwrecks, including the Rio Grande, a World War II German blockade-runner officially certified by Guinness World Records as the deepest shipwreck ever found, at 5,762 metres.

  The Ocean Explorer’s key feature was that she was equipped with two different frequency sonars optimized for two very different purposes: a 36 kHz unit for wide-range reconnaissance searching, and a 120 kHz unit for higher-resolution, close-in imaging. This was the absolute perfect blend of sonars to use when searching for wrecks, especially in ultra-deep water. It was akin to having a camera with both wide-angle and telephoto lenses without having to change out one for the other. I knew that if operated properly, the Ocean Explorer could initially detect a wreck at the extreme range of 2.4 kilometres (nearly 1.5 miles), but then zoom in during a second pass and resolve something as small as the ship’s anchor. One revelation from Ballard’s 1989 expedition was that all four of Bismarck’s 15-inch gun turrets had fallen out when the ship capsized and were now scattered around the hull. With so much heavy wreckage littering the seabed, there was every chance the debris field would give us the first indication of the wreck’s location.

  Sure enough, about three hours into line 1, the first sign of a definite hard target started to light up my screen, followed by a handful of bright yellow rectangular shapes characteristic of wreckage. In the place where I expected Bismarck’s 251-metre-long hull to be was a large crater at the head of a long curved chute, which I optimistically interpreted to be a slide scar representing the path the hull took as it slid down the steeply sloping seabed. Ballard had described Bismarck’s final resting place as the lower slope of an extinct undersea volcano, and the sonar image in front of me matched that description to a T. While others were thrown by the missing hull, I was confident we had found the wreck site and wasted no time in aborting the current search line and getting the ship and sonar to turn around to line up a second higher-resolution pass. There was a smattering of dissenting voices but they didn’t understand the navigational clues like I did. Bismarck’s hull simply had to be near this debris field; it was just a matter of pinpointing its location.

  Eleven hours later, the turn was completed and the sonar was at the start of the second line. Any doubts about whether we had found the wreck site soon evaporated. This second set of images matched the first but provided far more convincing detail. The huge crater Bismarck had caused when it impacted the seabed was now well defined, and there were fifteen large targets spread amongst numerous smaller hits. Once again there was no obvious sign of the hull, but I didn’t think it was worth spending fifteen hours running another sonar line. In the same amount of time we could recover the sonar, reconfigure the deck for ROV operations and have the Magellan 725 on the seabed taking actual pictures of the wreckage. I believed that was a better use of our dwindling schedule for the purposes of the C4 documentary. Although the Bismarck had lost a lot of her topside structure (turrets and bridge superstructure) in the sinking, we knew that the beautiful lines of the hull were undiminished, and this was what Gary Johnstone, the documentary director, was especially keen to film.

  Shipwreck sites can be quite confusing, and Bismarck’s was an especially difficult one to decipher. What you finally see on the seabed is an amalgam of damage inflicted during a sequence of events, including the British gunfire and torpedo strikes; the scuttling charges set off by Bismarck’s crew; the violent capsizing and sinking; the crushing forces as the wreckage hit the seabed; the ripping of the hull’s underside as it tobogganed 1,450 metres down the slope; and the corrosive actions of the sea over sixty years. There was no confusion, however, about the first objects we found when Magellan reached the seabed: a single pair of leather boots that foretold a scene of widespread death and destruction. Because leather holds up well in seawater, it is often the only visible material left behind where a human body once existed. Magellan didn’t need to move very far from this spot before another pair of boots was spotted, and then another, along with a leather jacket indicating that the crewman who had worn them might have worked in the engine room. As we paused the ROV to take in this scene, the images were a chilling and poignant reminder that thousands of men had died on this spot.

  We found the boots and jacket near the base of the slope where I wanted to begin the hunt for Bismarck’s hull, as it is easier to search moving up-slope rather than down. What I didn’t know at the time was that we had landed Magellan roughly 210 metres from one end of the hull. At this extreme depth there is zero ambient light, so our cameras could only see as far as the lights on Magellan could penetrate, which was about ten metres. For longer-range searching and navigation beyond the limit of lights, we use a scanning sonar, but the unit we were using only had a maximum effective range of 100 metres. Although we would have been able to close in on the hull in less than an hour if we’d known in which direction to move, we didn’t find it until nearly three and a half days later, having had to make three separate dives because of two equipment failures and another short spell of poor weather.

  While searching for the elusive hull, we did locate and film a lot of other wreckage, like two of the 15-inch gun houses, the mainmast and the bridge superstructure, so the dives weren’t wasted. However, the effort exhausted the entire team and my patience was stretched to the absolute limit. I believed the hull would be found at the bottom of the slide scar, but too many times the ROV pilots were getting sidetracked and chasing minor sonar targets outside the trench. To keep them focused, I told them they needed to be like bloodhounds and to follow the trail the trench laid straight to the wreck. The hut from which the ROV pilots operated was on a different deck from our control room and we communicated via an intercom system. As the ROV descended further down the trench, the tension ratcheted up a notch and became palpable. I spoke over the intercom in short, clipped bursts that reflected the tightness in my chest. The control room was packed, and anyone lucky enough to have a seat was perched on its edge.

  The ROV pilots spotted the hull first in the monitor of th
e scanning sonar, which we couldn’t see, but cheekily kept it to themselves, knowing full well what our reaction would be when it came into view. Suddenly, and without warning from my perspective, the picture in my video monitor changed and I was facing a curtain of black steel. ‘What the hell is that, right in front of you?’ I asked, not understanding how this enormous object hadn’t been picked up by the scanning sonar long before it appeared in my monitor. Richard Daily, the big gregarious Texan who had played this little prank, calmly answered, ‘That’s the Bismarck.’ Instantly, the room erupted in cheers. I dropped the intercom mic and raised both arms as the cheers turned to whoops and then laughter at Richard’s trickery. Mainly, though, I was just massively relieved. It should have been easy, but finding Bismarck had turned out to be a real struggle, and we deserved our brief moment of celebration.

  After the congratulations ended, we got down to business straight away and I asked the ROV pilots to start by conducting a full circumferential inspection of Bismarck’s fractured stern. In the sinking, or possibly when she crashed into the seabed, a section of her stern aft of the rudders detached from the rest of the hull. Whatever the cause, the fracture was remarkably clean, cutting straight across the full breadth of the ship in a way that exposed the welded construction of the after bulkhead. It was the one section of the ship where we could study its internal construction without having to make any penetrations with the ROV, a practice I had forbidden along with intentional touching of the wreckage.

  Channel 4 had invited two experts – Bill Jurens, a Canadian consultant on battleship design and gunnery, and Eric Grove, a British historian – to join the expedition and assess the damage suffered by both ships in an attempt to answer some basic questions, such as: how did Bismarck’s armour hold up against the British onslaught; was the Bismarck sunk or scuttled; and what actually caused the catastrophic explosion that ripped Hood apart and led to the death of every man on board save three? This was going to be a tall order in view of our limited schedule for forensic-style examinations, but at the end of the day C4’s sponsorship of the expedition was predicated on the making of television documentaries whose objectives were to inform, educate and entertain audiences. It was my job to balance all these different aspects, in addition to keeping control of the budget and schedule, so I had to take a pragmatic view about what was achievable and what was not.

  My approach in managing the various objectives was to make the most of the fact that we were running a 24/7 expedition, and that except for equipment or weather downtime the Magellan would be in the water filming the wrecks on a round-the-clock basis. I gave preference to the documentary film team for the daylight hours, while Bill and Eric’s detailed battle damage investigation was done mostly in the evenings, when activity on the Northern Horizon had quietened down. Our control room was completely blacked out from ambient sunlight, a necessity especially in the Denmark Strait, as we never had complete darkness there, with only about three hours of dusk each night. The rigid mealtimes on board were the best form of timekeeping, as nothing was more upsetting than missing your favourite meal of the day.

  Devoid of her 15-inch gun turrets and bridge superstructure, Bismarck was still one of the most magnificent-looking shipwrecks I had ever seen. The lines of the hull, especially the way her mid-ship girth narrowed to the knife-edge of her stem, were especially pleasing. As we looked more closely, however, the extraordinary pounding she had absorbed at the hands of the British fleet was plain to see. Considering the great number of shells fired at her (2,876) and the large number estimated to have hit (300 to 400), relatively few appeared to have been aimed at her side or waterline, where the damage could have led to a sinking. It wasn’t that the British shells didn’t penetrate Bismarck’s stout armour, because they did; even the 320 mm main armour belt had been impressively pierced by a large-calibre shell. Yet far more hits were scored on the superstructure, guns and deck. Whatever their reasons, the gun directors of the four British ships that shelled Bismarck aimed high at her superstructure and gun turrets. Admiral Tovey was absolutely right when he radioed, ‘Cannot get to sink her with guns’, although this signal would later plant the seed that the British had not sunk her at all. He was also right to stop the brutal slaughter of the escaping Germans and order, ‘Any ships still with torpedoes to use them on Bismarck.’

  Although Tovey’s unfortunate signal has led some to mistakenly believe that the British guns were not up to the job of defeating Bismarck, our expedition showed exactly the opposite. In fact, the surgical accuracy of the British gunnery was wholly remarkable. We found devastatingly destructive hits on Bismarck’s conning tower; on the barbettes for turrets ‘Bruno’ and ‘Dora’; on the aft gun director; on one of the main rangefinders found in the debris field; and most impressively on five of the ship’s six secondary 150 mm gun houses, which were all neutralized by a single well-placed shell. Tovey’s view from the King George V ‘after half an hour of action’ was that as a fighting unit Bismarck was essentially defeated. The shelling continued – almost as a form of target practice, which some British officers considered wasteful and humanly unpleasant – for another twenty minutes before torpedoes were called on to finish Bismarck off.

  Never before had anyone been able to document the damage caused by the torpedo strikes on Bismarck’s hull, which subsequently became the subject of a contentious debate about who could take the credit for sinking the ship. The fundamental question was whether Bismarck was sunk by the British or scuttled by her own crew. This question was first raised by Bob Ballard following his initial discovery of the wreck site in 1989. In an interview for the New York Times, he was quoted as saying he was satisfied that the Germans scuttled Bismarck, because ‘only scuttled ships tend to make it to the bottom in one piece’. I knew this was untrue because Blue Water Recoveries had found many ships sunk during both world wars in one piece on the seabed even though they had been sunk by enemy action, whether it was gunfire or torpedoing. A ship sinks when it loses all the reserve buoyancy keeping it afloat because its internal spaces have become flooded. It matters not whether that flooding is due to holes opened up in the hull by the enemy or by scuttling actions.

  I also knew that Ballard was unaware of the true extent of the torpedo damage, because in using a towed camera platform to photograph the wreck, he had only been able to look down on the main deck from above and couldn’t see the sides of the hull below the armour belt where the torpedoes would have hit. My advantage in using a free-flying ROV like Magellan was that we were able to look at all surfaces of the wreck from every angle. I could ask Oceaneering’s pilots to fly the ROV to any point on the wreck and basically have them hover in that position while we collected the best video footage possible. I also had the advantage of superior lighting and camera equipment that wasn’t around in Ballard’s day.

  In order to see the torpedo damage, we needed to position Magellan near the lowest part of the hull, where it was buried deep in the muddy seabed, and fly along both the starboard and port sides looking for breaches. I wasn’t surprised to find four gaping holes below the armour belt – two on the port side and two on the starboard – at locations that closely matched where eyewitnesses observed torpedoes to have exploded. Two of the holes were larger than normal but could have been caused by either multiple torpedo strikes or by being enlarged in the course of Bismarck’s slide down the volcano slope. The other two exhibited the unmistakable and classic signs of a torpedo explosion: hull plates splayed outwards by the internal explosion and the misalignment of heavy armour plates immediately above the hole. Despite my confidence in what I saw, others disagreed. Dr Alfred McLaren, a former US Navy submarine officer and ex-president of the Explorers Club – a club I have been a fellow of since 1991 – who dived to the wreck in a manned Russian submersible the month before us and again in 2002, appeared to completely discount the torpedo damage. In a second New York Times article to highlight the scuttling claims, he said: ‘We conclusively proved there was no
way the British sank that ship. It was scuttled.’

  When McLaren’s views were relayed to me by the journalist writing the article, I got the feeling that in addition to discounting the unmistakable torpedo damage, he was also overlooking the accounts of British and German eyewitnesses to the battle. For example, Baron von Miillenheim-Rechberg wrote in great detail about the extensive flooding Bismarck suffered before the final action; the two 14-inch shells from the Prince of Wales that struck the port bow caused the ship to be ‘down 3 degrees by the bow and have a 9 degree list to port’. As for John Moffat’s aerial torpedo that struck Bismarck’s stern on the evening of 26 May, Miillenheim-Rechberg wrote:

  The torpedo hit shook the ship so violently that the safety valve in the starboard engine closed and the engines shut down. Inspection by the damage-control parties revealed that the hole blown in the ships hull was so big that all the steering rooms were flooded and the occupants had been forced to abandon their stations. Then the after depth finder tube broke and water rushed through to the main deck. The after transverse bulkheads had sprung leaks and the upper and lower passageways on the port side of Compartment III and the centreline shaft alley were making water.

  By itself this information proves that an aerial torpedo was able to penetrate Bismarck’s defences and cause significant structural damage and flooding. Other reliable accounts reveal that Bismarck was hit by a minimum of six torpedoes and possibly as many as nine (three aerial and six ship-launched, with the ship-launched torpedoes carrying 90 per cent more TNT than the aerial types). On top of the flooding that resulted from the British attacks, German damage control parties were also flooding the ship to correct lists and to extinguish the fires that were raging throughout.