"Hitler's Lost Sub"
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NARRATOR: In the dark of night, a team of divers prepares for a dangerous expedition. Their journey will take them 60 miles offshore and a half century back in time.
During World War II, a German U-boat is stalking the coastline of New Jersey, hunting for American ships. Suddenly, an explosion rocks the boat. In an instant, thousands of gallons of freezing water flood in. She sinks to the bottom, taking her crew to a watery grave.
For decades, salt water eats away at the submarine until it is barely recognizable. So close to our shores. No one has any idea that this U-boat was ever here.
But one day in 1991, a fisherman loses his net—snagged by something on the bottom. A group of divers goes down to see what's there.
JOHN CHATTERTON (Dive team leader): The first thing that I saw was a hatch opening, and I looked inside, and I saw what was obviously a torpedo.
NARRATOR: These divers have been exploring shipwrecks off the coast for years, but they've never heard of any submarine at this location. Not knowing how old the wreck is, or what nationality, they report it to the US Navy.
BERNARD CAVALCANTE (US Naval Historical Center): And I checked some of my sources that I have here, of known wrecks off the East Coast, and there was no known wreck at that exact position.
NARRATOR: What began with a fisherman's accident now starts these divers on a journey through the dark history of World War II. When they're through, part of the record of the 20th century's worst war will stand corrected, and families around the world will finally learn the truth about their lost loved ones.
Their six-year quest to solve this mystery begins with a startling discovery.
JOHN CHATTERTON: On my second dive I went down, penetrated inside the wreck, and I brought back two bowls.
RICHIE KOHLER (Dive team member): And on the back of the dishes, plain as day, was the eagle and swastika, with the year 1942.
JOHN CHATTERTON: That proved that the wreck was a German U-boat from World War II.
RICHIE KOHLER: It shouldn't be there! According to the war records, there isn't supposed to be a U-boat for a hundred miles in either direction. And that's when the mystery really started.
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NARRATOR: In December, 1941, German submarines U-boats depart on a secret mission. They cross the Atlantic undetected, and take up positions a few miles off the East Coast. Their target is the United States.
HORST VON SCHROETER (Watch Officer, U-123): It was quite risky, because we didn't know what anti-submarine warfare had to be expected.
NARRATOR: Horst von Schroeter is Watch Officer on U-123.
HORST VON SCHROETER: We closed the shore within, say, two or three nautical miles. We smelled the forest ashore, and we saw the autos—the cars—running on the shoreway.
NARRATOR: The German plan is code-named "Paukenschlag," or "Drumbeat." It calls for an all-out surprise attack on American merchant ships. At war for barely a month, few suspect German U-boats are lurking within sight of shore. The attack begins January 13, 1942.
After fighting the British for two years in the Atlantic, the Germans find America easy.
Commander of U-552, Erich Topp:
ERICH TOPP (Commander, U-552): Compared with the difficulties in the Atlantic war, it was a shooting of hares.
HORST VON SCHROETER: It took one week, as I remember. Only one week all the time (sic), and we sank, I think, about ten ships.
NARRATOR: America is completely unprepared.
ERICH TOPP: And so, we had a very easy game there.
BERNARD CAVALCANTE: January was just a slaughter.
NARRATOR: January is just the beginning.
GORDON VAETH (US Navy Intelligence): And this went on all the time. Bodies and wreckage. And oil was constantly coming ashore—down the coast as far as Florida.
BERNARD CAVALCANTE: We were really afraid of them. We were scared. It was an unseen weapon.
NARRATOR: The US Navy assures the public it has the U-boats under control.
GORDON VAETH: Naturally, in time of war, you put your best foot forward. The Navy was saying, "Don't worry, we're taking care of these submarines, we're sinking them." In actuality, we hadn't sunk a single one.
NARRATOR: In 1942, at the height of Operation Drumbeat, the German U-boat seems almost unstoppable. But was this machine as effective as it seemed?
In a remarkable reversal, the hunters become the hunted. Barely two years after Drumbeat, the U-boats are suffering staggering losses. What then accounts for the U-boat's deadly reputation? If it truly was as lethal as its image would have us believe, how is it possible it was so decisively defeated?
By the end of the war, the Allies sink three-quarters of Germany's combat U-boats. To this day, some 68 are still unaccounted for.
A mere sixty miles from New Jersey, this is one of the lost U-boats. But no one knows which one.
RICHIE KOHLER: First we went down...dropped our stage bottles. At that point, he went forward. I recovered some objects, but it's (sic) all fused together.
JOHN CHATTERTON: Look's like they're spare gauge faces. They might have something written on them, so...
NARRATOR: For six years, the group of divers that discovered the wreck has been trying to learn which U-boat it is. The team leader is professional diver John Chatterton. John's partners are Richard Kohler, a businessman, and John Yurga, also a professional diver.
JOHN CHATTERTON: There you go.
JOHN YURGA (Dive team member) : Oh, boy. That didn't sound good.
JOHN CHATTERTON: We're going to see if we can find something here that's got an identifying mark on it, a U-boat number, a hull number, something like that.
RICHIE KOHLER: John, you know what this is? It's got commands from the commander to the engineer, or from the engineer to the commander.
JOHN CHATTERTON: After an attack where they've been heavily depth charged—this would be replacement parts for that. Here you go, Patrick.
NARRATOR: Every summer, these divers come here and search for artifacts, hoping one will identify the wreck. During the winters, they read and study blueprints, learning details about U-boats that will guide their diving.
JOHN CHATTERTON: That is going to be the determining factor.
NARRATOR: They do this work not for money, but out of stubborn curiosity. After six years, they still have no answer.
JOHN CHATTERTON: We're not archaeologists, but you don't see archaeologists out here trying to do this work. What we're trying to do is identify the wreck. There's no treasure. There's no loot. The payment for us is solving the mystery.
RICHIE KOHLER: We just want to positively identify this wreck. And then basically, our search would be over. Do you agree?
JOHN CHATTERTON: The first day I dove on this wreck, I said, "What? What is this thing doing here? How did it get here? What is it?" And we're still... we're six years later and we're still trying to answer those...those questions.
NARRATOR: The questions are simple, but finding answers means overcoming enormous obstacles. Every trip to the wreck takes eight hours. The divers leave at midnight to arrive by dawn. They average a half-dozen trips every summer.
But this far offshore, the weather is unpredictable. More than half the time, rough seas at the wreck site mean they cannot dive. Even in good weather, the diving is difficult and dangerous. The wreck is 230 feet down, in cold, murky water.
RICHARD KOHLER: The National safe diving maximum limit is supposed to be 130 feet. This is another 100 feet deeper. If anything goes wrong, you've got to fix it right then and there.
NARRATOR: Their bodies can only tolerate two dives a day, and no more than 30 minutes on the bottom. At this depth, any mistake can be fatal.
But for these divers the quest has become an obsession. No matter what it takes, they are determined to identify this U-boat.
This wreck will not give up its secrets easily. After a half-century underwater, it now scarcely resembles a U-boat. But some of its original features, like this gun mount, can still be discerned.
The port side rudder, one of two which steered the boat...a massive propeller, halfway buried in sand...the stove, where the lone cook prepared meals for 57 men...the officers' quarters...a rubber-soled shoe, worn to minimize noise and escape detection...valves for the diesel air intakes...gauges for the diesel engines...one of the torpedo tubes, probably still loaded...a torpedo.
Germany built more than 1100 of these stealthy machines during the war. Today, only a handful remain. One of them is on display in Chicago. U-505 was captured by the US Navy in 1944. 250 feet long, 22 feet wide, weighing 1100 tons, this boat had only one purpose: to destroy.
Looking at it from the outside reveals almost nothing about what made it work. Inside, it is a claustrophobic tube crammed with weapons and machinery.
Torpedoes. These half-ton underwater guided missiles were the U-boat's primary weapon. They were stored and launched from two torpedo rooms, one at each end of the boat. Twenty-five to 30 men would live crowded among the torpedoes for up to three months at a time.
On the surface, two nine-cylinder diesel engines drove the boat up to 18 knots, with a range of 11,000 miles. Underwater, electric motors took over, running off batteries located under the floor. But they had less than a quarter the power of the diesels. Submerged, the boat rarely went faster than two or three knots, with a range of barely seventy miles. Nor could it stay down long. Twenty hours was about the limit before the batteries ran out and the crew starved for oxygen.
At the center of the boat: the conning tower. And below it, the control room—a confusing maze of controls for steering, diving and surfacing.
It took about nine months to build a boat like U-505, and it cost roughly half a million dollars. Compared to any other warship it was cheap and quick to make.
But it was built to attack. Its only defense was to hide deep in the ocean. There, its survival depended on its pressure hull. Not visible from the outside, the pressure hull is the submarine's only protection against the ocean—a long tube of circular ribs covered with steel plate. It's all that stands between the crew and thousands of tons of seawater. To destroy a submarine, it just takes one break in the pressure hull—the ocean does the rest.
On the mystery wreck, the nature of the damage holds clues as to how the boat met its end. It must have been cataclysmic. The top of the pressure hull reveals an enormous crack—a giant split in the one-inch steel. This boat must have suffered a massive explosion. The damage is centered in the control room. The conning tower is blown completely off the wreck.
Whatever caused the explosion...with its pressure hull split wide open, the boat sinks like a stone, taking its crew to a death that cannot come fast enough.
Whichever U-boat this is, its crew must have known the risk of venturing into the deep. For as long as submarines have existed, men have been dying in them. But despite the danger, the submarine has a powerful attraction: stealth—a goal as ancient as war itself.
For centuries, designers around the world struggle to perfect a ship that can hide underwater. Submerging is easy. Early designs, like the one-man Turtle used in the American Revolution, dive by flooding ballast tanks with seawater. To surface, this water is pumped out again. Today's modern submarines use the same method.
But propulsion and a weapon are far more difficult problems.
Early submarines rely on inefficient hand-cranked propellers. To attack, they must attach a bomb to the bottom of an enemy ship, and try to get away—hopefully, before it goes off. These limitations make early submarines far more dangerous to their operators than to their enemies.
But the submarine is rescued from obscurity in 1866. An English engineer, Robert Whitehead, invents a bomb that can drive itself to the target from a safe distance—the torpedo.
Unlike the gun—the traditional naval weapon—the new torpedo strikes below the waterline, where ships are most vulnerable. Early torpedoes only go in the direction they are pointed. But in the 1890s, when the gyroscope is added, the torpedo can now steer itself.
ARTHUR BURKE (Engineer, US Naval Torpedo Station): When the gyro was installed in the torpedo, the torpedo became a smart weapon. It was guided, so that even if the target was 90 degrees bearing from where you were pointing, you could turn the gyro 90 degrees, and as soon as the torpedo was fired it would do a 90-degree turn and proceed to the target.
NARRATOR: Whitehead originally intends his torpedo to be launched from tubes on land. But this underwater guided missile turns out to be the perfect weapon for the stealthy submarine.
Now that it has a weapon, the submarine's remaining weakness is propulsion. At the dawn of the 20th century, motors replace hand cranking. Gasoline or diesel engines, which need air, are used on the surface. When submerged, electric motors run off batteries.
By a fateful accident of history, the stealthy submarine and the smart torpedo are perfected just on the eve of World War I. Ironically, Germany is the last naval power to adopt the new vessel, in 1906.
The German term for it is untersee boot—an underwater boat. In just a few years, the whole world will come to know and fear its abbreviation: "U-boat."
As World War I begins, the submarine is not expected to play a pivotal role. But only six weeks into the war, a single German U-boat, U-9, sinks three British cruisers in less than an hour. The world is astounded.
CLAY BLAIR (Historian): The loss of all these cruisers and 3000 men was a shock. It was like a Pearl Harbor for the British.
DR. GARY WEIR (Historian): This is the first time the submarine ever showed its...sort of...raised its ugly head, you know? In a warfare situation. And nobody was prepared for it.
NARRATOR: In Germany, the commander of U-9, Otto Weddigen, becomes a new kind of hero: the daring submariner, who can bring down the mighty British with this marvelous new machine.
DR. TIMOTHY MULLIGAN (Historian): For the German public, the image of the German submariner became very similar to what the American astronaut became for the United States public in the 1950s and 60s. That (sic) these men were warriors, but they were explorers. They were technicians. They were scientists. They were men who were able to do anything.
NARRATOR: One of thousands of young Germans mesmerized by the exploits of Weddigen is Erich Topp.
ERICH TOPP: There was a picture of him hanging in my sleeping room, and every night I saw Weddigen there. And, well, he was attacking. In the North Sea, he was attacking three cruisers...light cruisers...and he was sinking them! And of course at that time, that was fantastic success.
NARRATOR: Weddigen's success is especially remarkable given the primitive nature of his vessel. U-9 is not very stealthy. Its engines emit clouds of smoke that can be seen for miles. It takes seven minutes to dive just 30 feet. But it only needs a crew of 24. And any weapon that lets 24 men take down thousands of the enemy is hard to resist. Germany quickly capitalizes on this unexpected success.
Shocking the world, U-boats start attacking the cargo ships that keep England alive. But shock turns to outrage when a U-boat sinks the passenger liner Luisitania in May, 1915. 1200 people are killed.
Now, a different image of German submariners is born: U-boat men are bloodthirsty monsters, preying on innocent women and children. But despite the world's condemnation, the stealthy submarine is too effective not to use. There is nothing to stop it.
In Britain and America, scientists rush to develop weapons for anti-submarine warfare, or ASW. The first new device that results is the depth charge. A bomb, set off by water pressure, it explodes once it reaches a certain depth.
But the ships can only guess where the U-boat is. Tthere is still no way to find a submerged submarine. In April, 1917, U-boats sink one out of every four ships that sails for England. But the solution to the U-boat threat has been available all along. Not a new technology, it is a centuries-old naval tactic: convoying—putting ships in groups protected by escorts.
ARTHUR BURKE: That's the bait. That's what the submarines are looking for. So they're forced to go to the convoy if they're going to sink any ships.
NARRATOR: By concentrating ships into a few large groups, convoys empty the oceans. Most U-boats now go days without spotting a target. If a U-boat does find a convoy, when it attacks it reveals its position to the escorts.
ARTHUR BURKE: And the escorts are all armed, so it shifted the balance. A well-protected convoy would lose ships, but at the same time the escorts would get submarines, and it shifted the whole calculus of the equation.
NARRATOR: After three years of war, the British finally adopt the convoy system. It is a smashing success. In 1917, U-boats sink 3,000 ships; in 1918, only 134 ships are lost in convoys.
In November, 1918, Germany surrenders. The first submarine war in history is over. In only four years, this new weapon has sent over 5,000 ships to the bottom of the sea.
ARTHUR BURKE: And that was one-quarter of all of the ships that existed at that time. So this unproven experimental submarine, at the turn of the century, turned into a major maritime threat.
NARRATOR: When Germany surrenders, the Allies confiscate all her U-boats. But as the world celebrates peace, one U-boat captain is sitting in a British prison camp, planning a response to the convoy. His name is Karl Dönitz, and he is already preparing for another submarine war. In less than twenty years the U-boat will be reborn. And once again, thousands of sailors on both sides will die in watery graves.
There are hundreds of U-boat wrecks lying on the ocean floor. Five were sunk off the American coast, their positions recorded by the US Navy. The Navy's World War II records, still on file in Washington, list some 10,000 attacks on U-boats, but none at the location of the New Jersey wreck.
BERNARD CAVALCANTE: I had a pretty good handle on where the U-boat wrecks were, but not in the position that John Chatterton gave me.
NARRATOR: Nor do German records mention any U-boat lost here. The identity of this boat will have to be found in the wreck itself.
The divers begin making regular trips to the U-boat. They start searching randomly for any object that might contain information. At first, they are confident, even overconfident.
JOHN CHATTERTON: We'll come out here and we'll identify the wreck. How hard could it be? I think I might have even been the guy that...to say it...is, "how hard could this be?" Like, another...another day or two out here and we'll have this thing positively identified.
RICHIE KOHLER: It was like a flurry of activity. We figured we'd have this thing identified in no time. But events six years hence have proved us wrong.
NARRATOR: By the end of their first season the divers have learned little.
RICHIE KOHLER: Take up bowling.
JOHN CHATTERTON: Yeah, bowling. Bowling would be good.
RICHIE KOHLER: Golf...
NARRATOR:Over the winter, they gather information to better focus their search.
JOHN CHATTERTON: We pored over historic photographs of U-boats, propaganda films. The other thing we did was, we spoke to veterans and people who are knowledgeable in U-boat life. And we said (sic), "well, what could we bring up from the wreck site that would give us positive identification on this wreck?"
NARRATOR: A U-boat veteran suggests looking for an escape lung—an emergency breathing device used to leave a sunken submarine. U-boat sailors often wrote their names on their escape lungs and a name might help identify the wreck.
RICHIE KOHLER: Right where those shelves were, there is an escape lung there. What I'd like to do is to go to recover that.
NARRATOR: In dive after dive they sift through the debris and locate several escape lungs.
RICHIE KOHLER: I'm just trying to see if the mouthpiece is in here guys.
JOHN YURGA: You know, according to the guys in Germany, all these guys' escape lungs had their names on them.
RICHIE KOHLER: I don't see any writing. Do you?
JOHN YURGA: Whatever they wrote it on doesn't seem to have lasted.
JOHN CHATTERTON: We recovered several of them, none of which had any identifying marks on them.
NARRATOR: The escape lungs prove disappointing. By now, the divers have been through most of the wreck without result. But there are two crucial areas they have yet to search.
JOHN CHATTERTON: We've been everywhere inside the wreck with the exception of the diesel motor room and the e-motor room. And unfortunately, we just haven't been successful.
NARRATOR: The electric motor room may hold the key. The divers have learned that boxes of spare parts stored here were often marked with tags bearing the U-boat's number. But reaching the electric motor room means passing through the diesel room. And the divers learned early on that the diesel motor room is perhaps the most dangerous place in the wreck.
RICHIE KOHLER: I got my body halfway in the opening. I saw the cables hanging and all the debris just jutting out at angles. I kind of lost my nerve. It...it...it spooked me. You've got exhaust manifolds, pipes, plumbing, flanges, what? Cables galore. All these objects just trying to grab you, it seems at times. And not only that. Because the diesel motor room has all this huge equipment, you could bump into it, and that's when it chooses to break free—on top of you.
JOHN CHATTERTON: We're going over ground that we've already, like, looked at.
JOHN YURGA: Right.
JOHN CHATTERTON: We're rehashing it.
JOHN YURGA: You didn't come out with anything, did you?
(VOICE OFFSCREEN): No.
JOHN CHATTERTON: Everywhere else, we've been to at least once...
NARRATOR: Having exhausted all other possibilities, the divers feel they have no choice. They will attempt the dangerous passage into the e-motor room.
JOHN CHATTERTON: We've got to go where we haven't been.
NARRATOR: The plan is to enter the hatch, pass between the diesel motors, and continue into the electric motor room.
The attempt begins. They pass through the hatch as planned. But as they approach the diesels, they discover their path is blocked. A large oil tank, normally bolted to the ceiling, has fallen. The space below the tank is too shallow to permit a diver to pass. Above, the gap between the tank and the pressure hull is also too small.
Unable to continue past the tank, they abort the dive. A significant area of the wreck cannot be searched. It is a major setback. But the dive is not a total loss. On his way out of the diesel motor room, John Chatterton notices a sheet of metal that seems to have writing on it.
This sheet of aluminum is marked with a schematic diagram. But it's the small print in the lower corners that interests the divers.
RICHIE KOHLER: "Nine C, Deschimag-Bremen" That told us that this U-boat is definitely a Type 9C-40 German U-boat, built at the Deschimag plant in Bremen, Germany.
JOHN CHATTERTON: We know that it's a Deschimag-Bremen boat; that's our limiting factor.
RICHIE KOHLER: From there, we were able to say, "Okay, there's only, like, 25 boats of this type that were built at that plant."
NARRATOR: At last the divers have a clue that narrows the field. For this wreck to be a Type IX is not surprising. The Type IX was a long range boat, used to patrol distant waters—off Africa or America. It is designed in the 1930s, as Germany starts to rearm.
After World War I, the Germans are banned from having any submarines. But in 1935, the British allow Germany to once again build U-boats. The British are confident they have nothing to fear, because they now have ASDIC, or sonar, to locate submerged submarines.
But Karl Dönitz, commander of Germany's new U-boat force, thinks ASDIC is overrated. It only works underwater, so he will use his U-boats in a way the British are not expecting.
DR. TIMOTHY MULLIGAN: Dönitz wanted to use the boats more as surface torpedo vessels—vessels that could submerge and escape danger, but which would do most of their damage on the surface.
NARRATOR: To overcome convoys Dönitz will use group attacks. Large numbers of U-boats will silently stalk convoys by day and swarm in at night for the kill. Dönitz calls this "the wolfpack."
DR. GARY WEIR: Like an antibody in the bloodstream destroying a virus they will converge on a convoy. So what he needs are massive numbers of U-boats to accomplish that.
NARRATOR: But Hitler doesn't wait for the boats to be built. On September 1, 1939, Hitler invades Poland. Two days later, England declares war on Germany.
The German navy has only 57 U-boats—a fraction of what Dönitz needs. Still, he has not forgotten the lesson of Weddigen in World War I, who showed the world the power of a single U-boat.
Dönitz plans a daring mission. He will send Gunter Prien in U-47 into the home port of the British fleet. Six weeks into the war, Prien sinks the British battleship Royal Oak in its own harbor. It is a stunning victory.
In Germany, Prien becomes a legend—the greatest U-boat hero since Weddigen. Just as Dönitz predicted, ASDIC has made the British overconfident.
DR. WERNER RAHN (German Naval Historian): The British Admiralty, I think, overestimated their anti-submarine warfare capabilities, especially the ASDIC. And the first tactical approach of German U-boats was attacking not in a submerged stage, but on the surface.
NARRATOR: It takes a lot of nerve to attack on the surface. But Dönitz hammers home his message: the way to win is to be daring.
DR. GARY WEIR: He is going to be the kind of leader who will constantly push his people to be as aggressive as possible, on the edge of being caught, of being sunk, always on the brink of perhaps, recklessness. But he believes that only that will bring them victory in the end.
ERICH TOPP: Well, you always...you always have to take risk, that is clear. But it was a thin line. I had to be aware that I was responsible for my crew. On the other hand, my task was to sink ships.
NARRATOR: The U-boat men call this "the Happy Time." A desperate Winston Churchill turns to America. The US Navy begins escorting British convoys carrying vital supplies. Six months before Pearl Harbor, America is fighting an undeclared war against the U-boats.
One of those U-boats is commanded by Erich Topp. In the early morning of October 31, 1941, he spots a target.
ERICH TOPP: A convoy—in my eyes, of course, a British convoy.
NARRATOR: He fires a torpedo at what he assumes to be a British destroyer.
ERICH TOPP: Then, after a certain time, I saw a big explosion. Like a volcano!
NARRATOR: But the destroyer Topp has sunk is the USS Reuben James—technically, a neutral ship. It is a mistake Topp will never forget.
ERICH TOPP: After the war, I heard more than 100 men had been...were killed in the fire...in the explosion...in the cold water. And that, I never forget in my life. It is like a shadow that is lying over my life.
NARRATOR: Topp's tragic error might have had grave political repercussions. But five weeks later it doesn't matter. America enters the war anyway.
<ARCHIVAL TAPE>FRANKLIN D. ROOSEVELT (U.S. President): Since Sunday, a state of war has existed between the United States and the Japanese Empire.
NARRATOR: Two days after the Japanese attack Pearl Harbor, Hitler declares war on the US without consulting his navy.
DR. WERNER RAHN: When Germany declared war on the US it was, at this exact time, a surprise for the naval staff. And the navy was unprepared to send a U-boat force to the American East Coast.
NARRATOR: Dönitz has only five U-boats available. But he wants to attack as quickly as possible, before the Americans have a chance to organize convoys.
DR. WERNER RAHN: The German naval staff was, from the beginning, of the opinion, well...the Americans will introduce the convoy system in a couple of weeks, and then there will be no chance for our submarines against the traffic there.
NARRATOR: But weeks become months, and still there are no convoys.
GORDON VAETH: The United States Navy, and the United States generally, was unprepared for their onslaught. The ships, the merchant ships that operated along the coast line used their radios openly, in plain language. They sailed with their navigation lights on. They made it easy.
ARTHUR BURKE: A small number of German U-boats came to the East Coast of the United States and sank almost 400 ships. And that was the most massive military defeat the US Navy has ever suffered.
NARRATOR: As the sinkings mount, the British press the US to protect its coastal shipping with convoys. But Navy commander Admiral Ernest King refuses.
GORDON VAETH: He held to the view that a convoy that was not well-defended, was not well-equipped, was worse than no convoy at all.
NARRATOR: With a two-ocean war to fight and much of his fleet sunk at Pearl Harbor, King simply doesn't have enough escort ships.
DR. GARY WEIR: Admiral King was not a friend of the British, but neither was he a fool.
NARRATOR: Defending cargo ships isn't King's only problem. He also has to worry about American troops sailing for England.
CLAY BLAIR: We had to make a choice of whether we used our resources to protect troop ships or cargo ships. This is the key. And Admiral King said, "We're going to protect the troop ships. We will not lose one troop ship."
NARRATOR: Even as U-boats are sinking hundreds of merchant ships, the navy escorts over 150,000 American troops across the Atlantic. Not one is lost. By May, five months after Operation Drumbeat began, King finally has enough escort ships to begin coastal convoys.
GORDON VAETH: And when they did, the sinkings by U-boats practically dropped to nothing.
NARRATOR: The U-boats pull back into the Atlantic. Drumbeat is the U-boats' greatest victory of the entire war, but in the end it accomplishes little.
DR. DEAN ALLARD (US Naval Historical Center): It did not knock us out of the war. Our oil was coming from Texas by pipelines, and the U-boats couldn't sink the pipelines.
DR. GARY WEIR: Drumbeat was not an Atlantic Pearl Harbor. That's not the case at all.
NARRATOR: Never again will large groups of U-boats attack the US. But until the last day of the war, single boats continue to come right up to our doorstep—lone wolves on the prowl.
757 German U-boats were sent to the bottom during World War II, the vast majority in waters far too deep to dive.
In theory, at 230 feet, this New Jersey wreck is also too deep. Going to this depth on scuba technology is an invitation to trouble. And early on, trouble strikes.
JOHN CHATTERTON: Uhh...we had a fatality. And I can't say it really was unexpected, because we've had fatalities deep diving before on other deep wrecks like the U-Boat.
NARRATOR: While down at the wreck one of the divers, Steve Feldman, becomes unconscious and is swept away.
RICHIE KOHLER: That man's body was not recovered for six months. And when it was subsequently recovered...by that time there was no way that they can ascertain exactly what killed him.
JOHN CHATTERTON: It certainly had an impact on everyone diving the wreck. And some of the guys who were on the trip that day never went back to that wreck. And there were even some that never went back to diving.
JOHN YURGA: We all took a step backwards and said, "hey, we're diving deeper than the US Navy says is safe. We're at a point where oxygen becomes poisonous to the human body."
NARRATOR: Breathing air at extreme depths can cause confusion, called "narcosis," as well as seizures. There is an alternative called "trimix"—a blend of nitrogen, helium and less oxygen than air. But trimix is untested in recreational diving.
JOHN YURGA: The way we had looked at it in the past was that all it did was give you a clearer head, in that it reduced the amount of nitrogen narcosis you'd suffer at depth. But another thing it did was...it lowered the percentage of oxygen in the gas you were breathing.
NARRATOR: For safety reasons, the divers experiment with trimix. But they quickly discover safety is not its only benefit.
JOHN CHATTERTON: On air you've almost got a tunnel vision. Certainly your peripheral vision is not very good. When you go down on mix you...really, the wreck is almost alive and your peripheral vision is excellent.
JOHN YURGA: You can do repetitive dives. You can do two dives a day with trimix. And we were able to get a thirty-minute time on the wreck, whereas eighteen was my maximum time before that.
NARRATOR: Better vision and longer dives make a difference. Searching the crew's quarters, John Chatterton discovers what appears to be an ordinary table knife. But on closer look, it seems he may have found exactly what they have been looking for.
JOHN CHATTERTON: I was running my thumb over it, and I could feel some sort of writing on it.
RICHIE KOHLER: There was a name inscribed into the handle. And the name was Horenburg.
NARRATOR: At last the divers have learned the identity of a crewman. Someone on the mystery U-boat was named Horenburg. Whoever Horenburg may have been, he was one of 45,000 men who served in U-boats. Allied propaganda portrayed them as fanatical Nazis, but this was more myth than reality.
DR. TIMOTHY MULLIGAN: Membership in the Nazi party was prohibited if you were on active duty. You had to yield your membership in any political party.
NARRATOR: Most were in their teens or early twenties, and had started out full of romantic notions of adventure at sea. Not all were volunteers. But theirs was a service with a mystique.
DR. TIMOTHY MULLIGAN: U-boat crews got the best treatment—the best food, the best pay, better promotion potential—and the image of an elite service developed within the minds of the German public and within the minds of those who served aboard German submarines.
ERICH TOPP: You know, when we came back there was a big show in the harbor—flowers and ladies welcoming us! What the submariners did on board became present to the whole population in Germany.
NARRATOR: Newsreels made with actual combat footage were used to glorify the U-boats. But the newsreels never told the terrible truth about the odds of survival. Nearly 70% of the men who went to sea in U-boats died in them. Some 28,000 men shared the same fate as Horenburg.
Now, 50 years after he carved his name into its handle, Horenburg's knife seems to be the key to the mystery. If the divers can learn who Horenburg was—and which U-boat he was on—they may have identified the wreck.
JOHN CHATTERTON: Brad Sheard was standing next to me and he slapped me on the back, and he said, "That's...that's it! You've identified the wreck! All you have to do is find Horenburg."
NARRATOR: To learn more about Horenburg, John and Richie travel to Germany. They take their evidence to the U-boat Archive in Altenbruch, run by U-boat veteran Horst Bredow
JOHN CHATTERTON: Mr. Bredow.
HORST BREDOW (Curator, U-Boat Archive): Hello?
JOHN CHATTERTON: I'm John Chatterton.
RICHIE KOHLER: Guten tag.
JOHN CHATTERTON: We're the divers who...
HORST BREDOW: Have we already had contact?
RICHIE KOHLER: No, I don't believe so.
JOHN CHATTERTON: No. We found a U-boat off the coast of New Jersey.
HORST BREDOW: We must look for it, we must have a look for it. We go first upstairs to look for the boats, jah?
NARRATOR: Bredow's archive is the most complete source of information in the world concerning Germany's U-boats and the men who sailed them.
HORST BREDOW: This is the history of all 1171 boats. I will not say that the history is complete, but almost complete.
RICHIE KOHLER: We have some objects that we'd like to share with you.
JOHN CHATTERTON: The first piece of evidence here, this is a schematic diagram. And here, of course, it identifies it as a Type IX-C
HORST BREDOW: IXC, Deschimag, Bremen.
JOHN CHATTERTON: Deschimag, Bremen.
HORST BREDOW: Do you have an idea what boat it could be?
JOHN CHATTERTON: Yes. Richie, the knife?
RICHIE KOHLER: Ah, sure.
JOHN CHATTERTON: One of the things that we found off the wreck was this knife.
HORST BREDOW: You see on the alphabetical list of the killed men...
NARRATOR: Bredow's records include a file on each boat, as well as a list of all the men who died in U-boats.
HORST BREDOW: Horenburg...
NARRATOR: Remarkably, Bredow finds there was only one man named Horenburg in the entire U-boat service. His first name was Martin.
HORST BREDOW: Look, Horenburg, Funkmeister...Martin.
RICHIE KOHLER: These are alphabetical listings of all...
HORST BREDOW: Yeah. Of all killed men, yeah.
RICHIE KOHLER: And there's only one Horenburg?
HORST BREDOW: Only one Horenburg.
RICHIE KOHLER: Is the spelling the same on the knife?
HORST BREDOW: Yeah, the same. It's just the same.
NARRATOR: It turns out that Martin Horenburg served on several U-boats. The boat he died on was U-869. But according to Bredow 869 cannot be the mystery wreck.
HORST BREDOW: Horenburg was a crew member of U-869, and this is the boat sheet of U-869. And here you see it was lost at (sic) the 28th of February, 1945, in the middle Atlantic. Near Rabat.
NARRATOR: The record shows that U-869 was sunk off North Africa, near the entrance to the Mediterranean Sea.
RICHIE KOHLER: The records record that as off of Gibraltar, right? Off North Africa?
HORST BREDOW: Jah. It cannot be at the shore, or at the coast of New Jersey.
RICHIE KOHLER: It seemed pretty conclusive that this submarine, the U-869, is sunk off Gibraltar. So, how did Horenburg's knife get on this submarine?
JOHN YURGA: We thought that maybe someone stole Horenburg's knife. Maybe he gave it to a friend. Maybe Horenburg was transferred.
RICHIE KOHLER: All we know is that we have a German U-boat, with a knife, with the name Horenburg on it, and there was only one guy named Horenburg in the whole German navy.
NARRATOR: What seemed to be the most promising of leads has been no help at all.
JOHN CHATTERTON: Forget the Horenburg knife. It's a dead end. Start over. Go back to the wreck. Find something else.
NARRATOR: The more the divers learn about this wreck, the more enigmatic it becomes. Aside from its identity, one of the most puzzling questions is how it met its end. To find out more about what might have sunk the U-boat, John Chatterton shows a videotape of the damage to US Navy underwater demolition experts.
JOHN CHATTERTON: And they looked at the damage to the wreck, and they concluded that it didn't appear to them as though the damage was from depth charges.
NARRATOR: According to the Navy, depth charges would not cause damage this severe. They suggest the boat was sunk by something more powerful than a depth charge—perhaps a torpedo. But whose torpedo?
The records show the Allies never attacked a U-boat at this location. The divers are left to wonder if this boat was sunk by its own torpedo. Perhaps the U-boat spotted a ship, fired at it...only to have something go disastrously wrong.
ARTHUR BURKE: If a steering motor stuck, or a gyro tumbled, or anything else, the natural hydrodynamic trajectory for the weapon is to go into a circle. So once you start a torpedo circling, you become the prime candidate to get hit by your own torpedo.
NARRATOR: If a U-boat crew suspected their own torpedo was circling back, their only hope for escape would be an emergency dive.
It begins with the order "Alarm!"
CREWMAN SHOUTS THE ORDER: "ALARM! "
NARRATOR: To make an 1100-ton boat vanish, a complex series of events must unfold with precise timing. In the diesel motor room, the crew shuts off the diesels and closes the air intakes. Now the electric motors take over.
The commander gives the order "Fluten"—flood the tanks. Valves are opened, letting seawater into ballast tanks. Men who are not on duty run forward. Their weight helps point the boat down. The emergency dive is the most critical test a U-boat crew can face. Seconds mean life or death.
HORST VON SCHROETER (Commander, U-123): From the order, "Alarm," it took 30 seconds—30 seconds to disappear from the surface, and another 30 seconds to be on (sic) a depth of 60 meters. But that was only possible with a well-trained crew, of course. And 30 seconds can be a long time in war.
NARRATOR: For the scuba diver, submerging is also complex. As with a U-boat, diving and surfacing require careful precise timing.
On Columbus Day weekend, 1992, the divers get a grim reminder of how unforgiving the process can be. A pair of experienced divers, Chris Rouse and his son Chris junior are about to search the galley.
RICHIE KOHLER: The plan was that the father would stay outside, and Chris junior would swim into the wreck.
NARRATOR: Inside the wreck, something goes terribly wrong.
RICHIE KOHLER: The son had gotten past the galley, struck something, and it fell on him. And he was in a cloud of silt. He couldn't see and he couldn't move.
NARRATOR: He remains trapped for nearly 30 minutes. Then his father goes in looking for him.
RICHIE KOHLER: He managed to find the boy...extricated the kid...and they both exited the submarine.
NARRATOR: But by now they are running out of air and they cannot locate their spare tanks.
RICHIE KOHLER: I think at this point, they were both panicking. They were extremely low on air, and they made a decision. They just surfaced—from 230 feet.
NARRATOR: But a diver at 230 feet cannot just surface. Under pressure, his breathing forces more gas into his body than it can hold on the surface. At depth, his blood is now like the soda in an unopened bottle.
If the pressure is suddenly lowered, gas that was dissolved now forces its way out of the liquid in the form of bubbles. To avoid bubbles forming in his blood, the diver must decompress—come up in stages, allowing his body to reduce the gas gradually.
RICHIE KOHLER: The longer you stay down, the longer those stages are going to be. You come up to 110 feet, you have to wait for a minute, and so on and so forth, until you finally surface.
NARRATOR: In their panic the father and son come up without decompressing. Their bodies are still saturated with inert gas. No longer under pressure, this gas begins bubbling out of their blood.
JOHN CHATTERTON: The son could not use his legs and we literally had to drag him up the ladder.
RICHIE KOHLER: The father died at the back of the boat, but the last thing he did was tell us to take his son on board first.
JOHN YURGA: ...called the Coast Guard. They flew a helicopter out. We cut our anchor lines and started heading back in towards shore to meet the helicopter.
RICHIE KOHLER: The son lived on the boat. He lived for a couple of hours in the helicopter. And he died in the recompression chamber in the hospital.
NARRATOR: Three divers have now died on the U-boat. John Yurga is starting to wonder if the risk of continuing is simply too great.
JOHN YURGA: When the father and son team died, I looked at those two guys and said, "'I don't know that I belong here. If these guys, knowing as much as they did, died diving this wreck, what am I doing going to these depths and making these kind of dives?"
NARRATOR: The following week, John and Richie go back to the wreck to shoot video and analyze what went wrong.
RICHIE KOHLER: It was a very somber dive—to see their equipment strewn about the wreck with their names on it. They were good divers. And every dive I've ever made since then, that's in the back of my mind.
NARRATOR: The tragedy brings another dive season to a close. Over the winter the team will regroup.
JOHN CHATTERTON: It's not that we didn't think about that incident very seriously, but I don't think there was ever any consideration that maybe we should stop.
NARRATOR: Three more years of diving and research follow. But still they are no closer to finding the answer. Each has his own reason for continuing. For Richie, it is a sense of responsibility to the families of the lost crew.
RICHIE KOHLER: It's not a personal challenge. It's more that I think I'm doing the right thing. I think that if we drop the ball on this and stop, it'll just stay the way it had been for fifty years. No one knew it was there, and not really anybody cared.
NARRATOR: But for John Chatterton, it is the challenge of solving the mystery, finishing what he has begun.
JOHN CHATTERTON: I've corresponded with U-boat men, historians, authors. Nobody can tell me what boat this is. I don't want to give up, and the only other option is to carry it through to its conclusion.
NARRATOR: Now, in the spring of 1997, John Chatterton comes up with a daring plan to get into the electric motor room, where there may be boxes of spare parts that can identify the U-boat.
John will remove all his tanks of gas except one. Pushing this single tank in front of him, he will squeeze his body through the narrow space above the oil tank. Once past the obstruction, he'll put his tank back on and proceed into the e-motor room. To Richie, it seems foolish.
RICHIE KOHLER: It's not worth it to me. I'm not going to do that. It's too dangerous. I have kids. I don't think that it's a safe thing to do.
JOHN CHATTERTON: We have to figure out a way to get in there. Yeah, there's the potential for somebody getting hurt, for pushing a little too hard. I'm not 100 percent sure I can make it. But there's also experience and skill and ability, and I rely on that.
NARRATOR: Tomorrow morning, John Chatterton, with thousands of hours underwater, will make the most dangerous dive of his life.
Morning arrives. The tension is palpable.
RICHIE KOHLER: This is a very dangerous wreck. So far, three men have lost their lives. It's one thing if you're just going on a sightseeing dive, it's another thing if you are going to dive down to 230 feet and penetrate into this broken ship. It takes a lot. It really takes a lot. It takes a lot of nerve, and it also takes a lot of experience.
JOHN CHATTERTON: Richie?
RICHIE KOHLER: Yo.
JOHN CHATTERTON: If it looks like I'm having trouble, you give me as much time as you think you can safely give me to let me work it out myself. Anything that's three taps, three tugs or three punches means trouble.
RICHIE KOHLER: Got it.
JOHN CHATTERTON: And we're out of there.
RICHIE KOHLER: Got it, got it.
JOHN CHATTERTON: Cool?
RICHIE KOHLER: Yeah.
JOHN CHATTERTON: Let's do it.
NARRATOR: If John's plan works, he will soon enter a place unseen and untouched since the day the U-boat sank.
With Richie's help, John secures his decompression gases and removes his single tank. With only twenty minutes of gas, John swims through the hatch into the diesel room. Richie follows.
John squeezes over the collapsed oil tank. Once past the oil tank, he's on his own. He plans to be back in ten minutes.
John and Richie won't reappear on the surface for over an hour. As the minutes pass, the team can only wonder what's happening below.
While waiting for John, Richie searches the diesel room for artifacts.
It's been ten minutes. Richie can see John's light faintly in the distance. He squeezes in for a closer look. Something isn't right. John's blue tank is visible but he's not moving closer. Richie isn't sure what's happening, but there's nothing he can do to help. He has to start back.
The divers on deck know John is running late, but they don't know why.
RICHIE KOHLER: There was a problem with communications, and then he didn't come out. Which to say...made me a little apprehensive.
NARRATOR: Finally, John appears.
WILL : How you doing, John?
JOHN CHATTERTON: I've been better. I tried to pass you the camera back.
RICHIE KOHLER: Right. Which I figured (sic) you were done filming at that point.
JOHN CHATTERTON: I got in there, I got my tank back on, and pulled a big piece of wreckage from the starboard diesel motor—a piece of manifold or something. It wasn't a pipe.
RICHIE KOHLER: Accidentally?
JOHN CHATTERTON: Well, yeah. I didn't do it on purpose!
RICHIE KOHLER: No, because when you went in, you kicked a piece off...it's going to be on the video...and it hit me.
JOHN CHATTERTON: A big long piece of heavy steel?
RICHIE KOHLER: Yeah.
JOHN CHATTERTON: And I tried to get out from underneath it, and then it, like, swung down around and landed in my lap. You know, it wasn't so heavy I couldn't lift it up, but I couldn't get it off of me!
RICHIE KOHLER: So what did you do for twenty minutes on the other side of the engine? I'm not being a wiseguy...
JOHN CHATTERTON: I spent the whole dive trying to get the steel off of me!
RICHIE KOHLER: Did you see my light? Every so many minutes, I'd come by and swing the light?
JOHN CHATTERTON: Yeah. Somehow it didn't warm my heart any, but...
NARRATOR: Pinned down by a piece of wreckage, John is lucky to escape with his life.
RICHIE KOHLER: I knew something wasn't going right.
NARRATOR: The next morning, John tries again. With John past the obstruction, Richie hands him the camera.
Now holding the camera, John passes through the door to the rear of the diesels and, for the first time, enters the electric motor room.
On the right, controls for the electric motor...a fuse panel...spare parts boxes. If John can break them loose without causing debris to collapse, one of these may finally identify the wreck.
Back at the obstruction, Richie has been waiting nearly twenty minutes, the memory of yesterday's near disaster fresh in his mind.
At last, John reappears with a box. He hands it to Richie. They send it up on a lift bag.
RICHIE KOHLER: The bag make it up, Jen?
JENNIFER : Bag's up!
RICHIE KOHLER: Alright! It went right according to plan. John went in, I stayed on top of the obstruction, it seemed like forever. Then, all of a sudden, he came back. I see his light flickering in the distance. He just hands me this big green bag and I had to, kind of like, lump myself out of the wreck.
JOHN CHATTERTON: I got the one box out, handed it to Richie, and I went in for the second box. I couldn't break it free, then I went to go out.
JOHN YURGA: Did the bag come up?
JOHN CHATTERTON: Well, we got one box out, there's a bunch more down there. I wanted to get as many shots at this as we can, but we'll take a look, we'll see what we got.
JOHN CHATTERTON: A tag—117.
JOHN YURGA: That's not a U-boat number, though.
JOHN CHATTERTON: No, no.
(VOICE OFFSCREEN): Down at the bottom corner.
JOHN CHATTERTON: Whoa, whoa, wait a minute! Wait a minute right here!
JOHN YURGA: What's it say?
JOHN CHATTERTON: U-869!!!
JOHN CHATTERTON: Interestingly enough, I think it took us longer to identify this wreck than it did to actually fight the war!
JOHN CHATTERTON: Absolutely, positively, this is the U-869. We've got the schematic diagram showing it's a Type IXC-40. We've got the Horenburg knife, which places Martin Horenburg on this ship. We've got the tag here that says "U-869," which was, historically speaking, the ship that Horenburg was on. But, the U-869 is listed as being sunk off Africa. This rules it out. It's definitely, beyond any shadow of a doubt, the 869. The page of history that has the 869 being sunk off the coast of Gibraltar has got to be rewritten!
NARRATOR: After six years, and three deaths, the divers have finally identified the mystery wreck: U-869.
But now, a new mystery emerges: why was U-869—Martin Horenburg's boat—here, instead of Africa?
The final entry in U-869's war diary has the boat leaving for her first patrol on the 23rd of November, 1944, just two and a half years since the U-boats' triumph in Operation Drumbeat. Now, Drumbeat and the Happy Times were little more than distant memories from a far different war.
U-boat Commander Dönitz had originally planned only to fight England. He never envisioned what it would mean to face the United States as well.
DR. WERNER RAHN: Most of the German military and political elite underestimated the capacity and the resources of the United States of America.
NARRATOR: One of America's most important resources is science. At universities and research centers scientific teams are developing new technologies to hunt U-boats.
ARTHUR BURKE: And they initiated a fairly heavy effort on this, including MIT, Harvard Underwater Sound Laboratory, Columbia University, Western Electric, Bell Labs—sort of an all to the wall effort.
NARRATOR: One focus of the scientific effort is radar. Since the 1930s, German scientists have also been working on radar. Though aware of this work, Dönitz fails to appreciate the magnitude of the threat.
DR. TIMOTHY MULLIGAN: He rather ignored the comments of an observer, who pointed out that much of his surface operations would be detected by radar, which was then being developed by all the navies. And Dönitz sloughed that off, saying, "Well, we're not going to worry about that."
WERNER HIRSCHMANN: All of the sudden during the war, there was a tendency that we were surprised by aircraft without knowing how they could find us. Slowly, slowly, it developed that yes, they must have radar.
NARRATOR: Beyond radar, Dönitz's greatest miscalculation is his obsessive use of radio. He sends some boats as many as 70 messages a day.
WERNER HIRSCHMANN: Dönitz was rather nosy. He wanted to know from us quite often how we were doing, where we were, and that sort of thing.
NARRATOR: The constant radio traffic exposes the U-boats to Allied high-frequency direction finding, or "huff duff." If a U-boat uses its radio, huff duff can pinpoint its position, using triangulation.
WERNER HIRSCHMANN: If we sent any signal whatsoever from our submarine, we practically were giving away our location at that time.
NARRATOR: Together, radar and huff duff force the U-boats to submerge. And a submerged U-boat is too slow to catch a target. It is also too slow to escape. The ships above are hunting it with sound. All the men can do is remain silent.
WERNER HIRSCHMANN: We tried to be as quiet as possible inside the boat. We took our shoes off, and we were only walking around in socks. And anybody who dared to cough or drop a spoon was immediately ostracized and considered to be an absolute enemy of the boat.
NARRATOR: When an escort locates a U-boat the depth-charging begins.
WERNER HIRSCHMANN: It is a scary experience to hear a depth charge dropping into the water, and then expect, in about five or ten seconds, an explosion to go off which one does not know at this particular time one will survive.
After the explosion goes off, then of course the next one is already coming, and this can go on for 10 hours at a time, with hundreds of depth charges. And each one of those is really quite a strain on your nerves, because all you are doing is sitting and waiting for something to happen. There is nothing you can do. You can just sit there and wait.
NARRATOR: Slowly, but inexorably, the Allies are gaining the upper hand. The turning point comes in a single month the U-boat men will forever remember as "Black May."
ERICH TOPP: May '43, when, in one month, 41 submarines were destroyed.
WERNER HIRSCHMANN: The hunters of the early years had become the hunted of the latter years. The "Happy Times" had changed to what we called the "Zauergherkinzeit" or "Sour Pickle Time." We did not have any fun out there anymore.
DR. TIMOTHY MULLIGAN: In the autumn of 1943, a crisis in morale began to develop within the U-boat service, simply because there was the obvious recognition that they were outmatched by the Allies.
WERNER HIRSCHMANN: It became very questionable. Why do we go out there? When our Flotilla Chief could say to us when we left, "Never mind sinking ships, just come back, please."
NARRATOR: Coming back is getting harder and harder to do.
Aircraft now patrol the entire ocean. The only way to avoid them is to remain constantly submerged. But that is impossible.
DR. TIMOTHY MULLIGAN: A U-boat of that period, as earlier in the war, had to spend at least four hours on the surface every 24 hours in order to recharge its battery. By late 1943, the omnipresence of Allied aircraft had eliminated all safe areas in the ocean.
NARRATOR: Even at night or in dense fog, an airplane with radar can detect a U-boat on the surface. Strangely, U-boat Command has long ignored a Dutch device that allows a submarine to remain submerged.
DR. TIMOTHY MULLIGAN: Finally, belatedly, U-boat command introduced the mass use of the schnorkel, a very simple device and one that did not significantly improve operational performance, but which at least allowed U-boats to recharge their batteries while submerged without danger of attack.
NARRATOR: The schnorkel is a mast that can be raised like a periscope. It sucks fresh air into the boat for the diesels and the crew, and vents poisonous exhaust out.
The schnorkel allows U-boats to stay hidden. But their slow underwater speed cripples their ability to hunt. What Dönitz really needs is a design revolution: a vessel that can remain constantly underwater.
Dr. GARY WEIR: The concept argues that we have a submarine, a vessel whose natural habitat is below the surface and not on the surface. It's a step out of necessity, because on the surface means death.
NARRATOR: A true submarine has long been the dream of Professor Hellmuth Walter. Since the 1930s, he has been working on a turbine that runs off hydrogen peroxide, H2O2. Since this fuel contains its own oxygen, the engine needs no outside air. For underwater speed, he uses a highly streamlined hull.
During 1940, in utmost secrecy, a Walter prototype is tested and reaches an astounding 30 knots underwater—four times faster than any submarine in the world.
But hydrogen peroxide is desperately needed for Hitler's V-2 rockets.
Work on the Walter turbine grinds to a halt. But Walter's use of streamlining becomes the inspiration for a new U-boat that will revolutionize submarine war: the Type 21.
On the surface it uses ordinary diesel engines. But its electric motors have five times more power than a conventional U-boat. With its massive banks of batteries, the Type XXI is actually faster underwater than it is on the surface.
Gone are the deck guns, platforms and railings. The Type 21 is not intended to fight on the surface. In the long history of the submarine, this is the first true underwater craft.
DR. GARY WEIR: They could replenish their air through the schnorkel, they could recharge their batteries, and doing 17 knots submerged was absolutely unheard of. The US Navy and the Royal Navy had no way to respond to it. This is what gave ASW officers in surface ships nightmares.
NARRATOR: But the Type 21s aren't ready until the last week of the war.
ERICH TOPP: I had one of these Type 21 submarines, and I was the second boat that went out. First of May, 1945! So it was too late.
NARRATOR: The Type 21 U-boat will redefine the future of the submarine. But it has no effect on the outcome of the war for which it is designed. In the end, the German U-boat is decisively defeated.
WERNER HIRSCHMANN: When you are being told today that German submarines sank two thousand ships and so many millions of tons, they are not telling you what a ridiculously small percentage that actually is of those ships which crossed the Atlantic without ever being bothered by a German submarine.
CLAY BLAIR: In reality, the German U-boat in World War II failed. Failed badly. They sank only about one percent of all shipping by the Allies anywhere. In other words, 99 percent of our ships, no matter where they were going, got through.
NARRATOR: Still, the U-boat threat has tied down Allied resources in the Atlantic that could otherwise bring the war to Germany.
DR. TIMOTHY MULLIGAN: Hitler always said, "The U-boats are my first line of defense." They were to keep the Anglo-American enemy at arm's length while he fought his war in Russia, and in the death camps of Auschwitz.
NARRATOR: To satisfy Hitler, the U-boat crews are deliberately sacrificed. In the closing months of the war, the life expectancy of a U-boat man is barely 60 days, yet Dönitz keeps sending them out.
DR. TIMOTHY MULLIGAN: The U-boat service lost 28,000 dead and 5,000 captured, out of a total force of perhaps 45 to 48,000 men. A permanent casualty rate of over 70 percent. No branch of an armed forces has ever sustained those kind of losses and kept functioning.
WERNER HIRSCHMANN: In spite of the fact that of ten submarines leaving port perhaps two were expected to come back and eight were not, when we left we were absolutely sure we were going to be one of the two which would come home. This of course is a totally irrational approach to the problem, but it helped us go out time and time again.
NARRATOR: But even the most optimistic U-boat man might have hesitated to go out had he known the greatest secret of the U-boat war. The Allies have broken the German code. By decoding Dönitz's radio messages, they know where each U-boat is headed even before it gets there.
A machine called Enigma encodes all German messages. Because it uses millions of random letter combinations, German experts assume Enigma cannot be broken. But British intelligence cracks the code.
ERICH TOPP: They were able to decode, within half a day round about, they were decoding all the messages that were sent from the submarine center to the boats!
NARRATOR: Some U-boat commanders suspect the Allies are reading their messages, but they cannot convince Dönitz.
ERICH TOPP: We had always the meaning that something must be happened in this field (sic)! But Dönitz and his experts said, "Impossible. There are millions of possibilities we can put into the Enigma machine, and it's impossible for somebody to break it."
NARRATOR: The Allied codebreaking, called Ultra, is one of the greatest secrets of World War II. At the time, Ultra enabled ASW forces to track and hunt down individual U-boats. Today, Ultra can help NOVA piece together the story of U-869's last patrol.
Radio is central to the story. And so is Martin Horenburg. On U-869 he is the Chief Radioman.
The story begins on the 23rd of November, 1944. After 11 months of training, U-869 is ready to go. Her captain is 26-year old Helmut Neuerburg. This is his first command.
December 8th, 1944. U-869 leaves Norway on her first patrol. She sails for the Atlantic.
Three weeks later, U-boat Command sends 869 her assignment: patrol the approaches to New York harbor. U-869 is required to signal back, and acknowledge her orders. But after several days, U-boat Command has heard nothing.
In fact, U-869 has answered, but Command has not heard her. The problem may be weather, or perhaps trouble with 869's radio. Whatever the reason, both 869 and U-boat Command are trying to communicate, and not hearing each other.
But Ultra codebreakers are hearing both of them. They now know U-869 is heading for New York. Meanwhile, U-boat Command has grown concerned that 869 may be low on fuel. They change her orders to someplace closer, Gibraltar.
CLAY BLAIR: U-boat Headquarters wrongly assumed that she had used up a great deal of fuel. So they said, "Okay. She'll never be able to get to America with the fuel she has, and get back."
NARRATOR: U-boat Command is now expecting 869 to arrive off Gibraltar by February 1st. But she never acknowledges her new orders. The codebreakers wonder if perhaps 869 missed the signal, and is continuing to her original assignment off New York.
Throughout February, the Allied codebreakers remain confused. Is U-869 patrolling off Gibraltar? Or New York? Wherever U-869 went, by March 5th, the codebreakers assume she is now probably homebound.
May 8th, 1945. The war in Europe is over. Germany signs the surrender. The ground troops lay down their arms immediately. U-boats at sea are ordered to surface and surrender, but the Allies fear many may disobey.
Hundreds of boats fail to return. To be sure none have escaped, the Allies review the German loss records.
In the case of U-869, German records show she was ordered to Gibraltar and presumed lost there sometime around February 20th.
The US Navy looks at its records for the Gibraltar area. They find three attacks that might have sunk U-869, and conclude she was probably sunk by the USS Fowler and the French ship L'Indiscret on the 28th of February.
Their conclusion becomes the official record of U-869's fate. It is this story that is engraved on the wall of Germany's U-Boat Memorial, and told to the families of her crew.
But in all probability, U-869 never receives her new orders. She does not go to Gibraltar, but continues on to New York and disappears. Until, half a century later, the divers uncover her story.
Three months after identifying the wreck, John and Richie return to Germany. Again, they visit Horst Bredow's U-boat Archive—this time, to correct the official record of U-869.
JOHN CHATTERTON: When I came here to see you last, we had the Horenburg knife.
HORST BREDOW: And that is a problem, because Horenburg...I will show you...
RICHIE KOHLER: We've done some, ah, research on this.
HORST BREDOW: Yeah, but look. Horenburg...
NARRATOR: Bredow is not easily convinced. He has a hard time believing his records are wrong.
HORST BREDOW: He was killed on U-869...
RICHIE KOHLER: That's the U-boat that we've been working on.
HORST BREDOW: ...on U-869. And now I will show you, U-869 has not been in the area you found this boat!
JOHN CHATTERTON: If you go back, and you research the original documents, you...
HORST BREDOW: But, it isn't...what? I don't believe here!
JOHN CHATTERTON: ...you might come to the same conclusion.
HORST BREDOW: But I don't believe it. It's not ...I, I cannot believe it. It's...it...it...it is impossible, because we exactly know, exactly know the position where it was lost!
JOHN CHATTERTON: Herr Bredow, what we did was, um...
RICHIE KOHLER: At great difficulty, we've been able to get inside the wreck...
HORST BREDOW: Yeah, yeah
RICHIE KOHLER: ...and recover an object that, hopefully, would have the U-boat's number. Now, as you can see, it's deteriorating terribly.
HORST BREDOW: Yeah, yeah, yeah.
JOHN CHATTERTON: But on the face here...
RICHIE KOHLER: Was two tags.
JOHN CHATTERTON: One tag was mounted there, with that number on it, and Richie's cleaned up the other tag.
RICHIE KOHLER: And, as you can see, sir, it says "U-869."
HORST BREDOW: (Whistles)
RICHIE KOHLER: This came from the New Jersey coast. Somehow, an error was made, and the U-869 operated off the coast of New Jersey...
HORST BREDOW: That's right.
RICHIE KOHLER: ...where she ultimately died.
HORST BREDOW: If this is original, I would say you are real right, real right.
RICHIE KOHLER: We have photographic evidence of the recovery.
HORST BREDOW: This is original, jah?
RICHIE KOHLER: Yes, sir.
JOHN CHATTERTON: Yes, sir.
HORST BREDOW: That is...that shows real...that it must be...must have been U-869. Jah? This is a 'beweis...'
RICHIE KOHLER: Evidence.
HORST BREDOW: ...a proof, a real proof. Now I believe you are right.
RICHIE KOHLER: Fantastic.
HORST BREDOW: I believe you are right.
JOHN CHATTERTON: Well, thank you. It took us six years, but, um...
HORST BREDOW: Six years for one boat?
JOHN CHATTERTON: Yes, sir.
HORST BREDOW: I took 50 years for 1171 boats. Do you understand my problem? (laughter)
JOHN CHATTERTON: Yes, sir. You have a better average than I do. (laughter)
HORST BREDOW: You should be my cooperators at the U-Boat Archive.
JOHN CHATTERTON: Well, thank you very much.
HORST BREDOW: It's really true. Jah, thank you.
RICHIE KOHLER: She's come home.
HORST BREDOW: Jah, thank you very much.
RICHIE KOHLER: You're very welcome, sir.
HORST BREDOW: Thank you for these words. Thank you. Coming home, jah.
NARRATOR: Half a century after she vanished without a trace, the final resting place of U-869 is now a matter of record. But questions about U-869 linger. Why she missed the message redirecting her to Gibraltar and what caused her to sink will always remain mysteries.
What can be said is that U-869 went out on a nearly suicidal mission late in the war. She survived barely two months, and like one-third of all U-boats sunk, was lost on her first patrol.
Radioman Martin Horenburg had been in U-boats since the war began. It was practically a miracle he was still alive when 869 sailed. Little is known about the other crewmen, but three families have been located.
Willi Rothsprak was a machinist on U-869. His brother Johann was put to work at the Deschimag shipyard when he was fourteen. It's possible Johann helped build the boat his brother died in.
Hellmut Neuerburg, Captain of U-869, left behind a three year old son, Jurgen. Today, Jurgen is a doctor in Hamburg. Before his father left, he wrote Jurgen a farewell letter.
DR. JURGEN NEUERBURG (Son of U-869 crewman): Soon, Poppi must go with his U-boat in the sea, and we all hope that he will see us again in peaceful times. That's the last I see of my father.
NARRATOR: Seaman Otto Brizius would have had his twentieth birthday in February, 1945, right around the time that 869 sank.
Today, Otto's sister lives in Maryland, a few hours from the New Jersey coast. Her name is Barbara Bowling. All she has ever known about her brother's death is that he was lost in a U-boat off Gibraltar.
Richie Kohler has gotten her address from sources in Germany. Now he's come to tell Barbara what the divers discovered about her brother's boat.
RICHIE KOHLER: When he was born, where was he...
BARBARA BOWLING (Sister of U-869 crewman): Well, he was born in a little village in Germany, and the name of the village is Dernbach, and his name was Otto Brizius.
He was very skilled. He was very good with his hands. So I don't know whether they picked him because of his background...of his schooling he had...
NARRATOR: Otto is picked for the U-boats when he is barely seventeen. He never returns. The family is told only that Otto was lost off Gibraltar. That is what Barbara still believes.
BARBARA BOWLING: They were declared missing, but my Dad needed to know more. So he wrote them, and this is basically the letter coming back, saying that U-boat U-869 was running low with fuel. And it was declared missing the 20th of February, '45. And then it says, "I had hoped that I would have had better," you know, "news for you about this." So I guess my Dad always hoped...he wanted to know, you know?
RICHIE KOHLER: Ah...I found an unknown German U-boat off the coast of New Jersey.
BARBARA BOWLING: Uh huh.
RICHIE KOHLER: And, ah, me and my partners were diving, and one day we went out and we accidentally stumbled on this U-boat. So we tried for the next few years to recover items from the wreck. And we found a knife, and on the knife's handle was a name, and the name was Horenburg. And I wrote to the Wast organization in Berlin, and I requested information about this.
BARBARA BOWLING: Right.
RICHIE KOHLER: Well, they gave us a U-number based upon that. But they said it can't possibly be that U-boat because that U-boat was not ordered to New Jersey.
BARBARA BOWLING: Don't tell me it's that one? Don't tell me that was Otto's U-boat!
RICHIE KOHLER: Ah, we positively identified the U-boat last year by bringing up tags out of the engine room that say "U-869." And I came here because I wanted to tell you that I found your brother's boat. And I'm positively...
BARBARA BOWLING: (crying) I'm sorry.
RICHIE KOHLER: That's all right.
BARBARA BOWLING: I mean, all these years, we had thought...I mean, my father...I mean he was...he believed, you know, he was there. And now, he...he made it to the coast of New Jersey?
RICHIE KOHLER: Yes. Sixty miles off shore.
BARBARA BOWLING: But basically, nobody...I mean, they all perished?
RICHIE KOHLER: They all perished. It's my theory, and I have backing from many naval experts, that the explosion which sank this U-boat was most likely self-inflicted. Ah, the torpedo failed, and came back in a circle, and they sank. I have brought for you my report on the U-869 which documents everything that we've done for the last seven years. And on the cover is a drawing of...
BARBARA BOWLING: Okay, that's how it was? That's how you found it?
RICHIE KOHLER: That's exactly how we found it.
BARBARA BOWLING: Unbelievable. It's just, it's just mind boggling. He made it all the way over to here, over to America. I'm just totally stunned. I mean, yeah, he's close! He's actually close. That's all I can say. He's close to us. And, um, that's a good feeling.
In 1999, this film was broadcast in Germany.
Following the broadcast, a man contacted the producers with a remarkable story.
He had survived U-869.
NARRATOR: Out of the 57 men assigned to U-869, one was saved by a twist of fate.
Just before the boat left, Herbert Guschewski was hospitalized with pneumonia and missed her departure.
Like the families of 869's crew, he always believed his boat was lost off Africa—until he saw this program.
HERBERT GUSCHEWSKI (Crewman, U-869): I couldn't believe it. I just couldn't believe it. For 55 years, I thought the boat was off Casablanca, off Morocco. Knowing it's in a different location doesn't really change anything. But since I saw this film, I've been very moved. I feel all stirred up inside. I have nightmares. It's all come back to me..the war...all we went through, all we had to endure for no reason.
I think of the ones I was close to. Radioman Horenburg, Leo Platt. They were all close to me. Our lives were intertwined. Somehow, I was saved. I don't know why. It was fate, destiny, I don't know.
NARRATOR: For most of us, World War II exists only in photographs and moving pictures, distant in time and place. But the cost of the war is still being paid today...by survivors..by relatives of those who lost their lives...by those who were only children at the time...and by some who were not even born when the storm was raging.
Like U-869, the scars of the Second World War are still there, hidden beneath the surface, yet closer than we realize.
Announcer: Hitler's lost sub lies 100 feet below the Navy's limit for recreational diving. On NOVA's Website descend to the wreck of U-869 yourself and encounter the hazards these divers are up against. At PBS.org or America Online keyword PBS.
To order this show or any other NOVA program for $19.95 plus shipping and handling, call WGBH Boston Video at 1-800-255-9424.
Einstein called it his greatest blunder but now his abandoned theory may be coming true. A mysterious force is pushing against gravity. The universe is beginning to accelerate in its expansion. Runaway Universe, next time on NOVA.
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Hitler's Lost Sub
Narrated by Roy Scheider
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