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00:02Next on Secrets of War.
00:04It was the longest, most crucial battle of World War II.
00:08The struggle for the Atlantic pitted Germany's lethal U-boat fleet
00:12against every weapon the Allies could muster
00:15to protect their vital supply routes to Great Britain.
00:19The story of naval intelligence, code-breaking and code-stealing
00:23in the Battle of the Atlantic is next on Secrets of War.
00:40The story of naval intelligence, code-stealing in the Battle of the Battle of the Battle of the Battle of
00:42the Battle of the Battle of the Battle of the Battle.
01:09The story of naval intelligence, code-stealing in the Battle of the Battle of the Battle of the Battle of
01:11the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle
01:11of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the
01:11Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of
01:17the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle
01:19of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the
01:19Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of
01:19the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle
01:19of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the
01:20Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of
01:20the Battle of the Battle of the Battle of the Battle of the Battle of the Battle of the Battle
01:36On the 1st of September, 1939, Germany invaded Poland.
01:43Two days later, England declared war.
01:47Almost immediately, the legendary Battle of the Atlantic was joined.
01:52This was a conflict neither side was prepared for.
01:56There were only 27 ocean-going U-boats in the German fleet,
02:00and the Allies had barely enough anti-submarine warships to counter even this small threat.
02:09Both sides braced themselves for the onslaught.
02:17After France fell to Hitler's Blitzkrieg in 1940,
02:20the balance of power at sea as well as on land shifted strongly to Germany's advantage.
02:30Britain was dependent on the supply of men, equipment, and food from North America to continue her war effort.
02:40German bombing raids had battered England's weapons production.
02:44Britain could not stand alone.
02:48Supplies had to cross the Atlantic, and that could be achieved by shipping alone.
02:55Convoys, which had been started on a limited basis at the outbreak of war, were rapidly expanded,
03:00and additional escort ships were scraped together in desperation.
03:06Grand Admiral Karl Dönitz of the Kriegsmarine, the German Navy, had one mission.
03:12To eliminate these convoy supply routes and throttle the British enemy.
03:18All available German U-boats were ordered to attack the convoys on their way to England.
03:31The Battle of the Atlantic was a secret war for information.
03:36In a vast ocean, coded communications made the difference between finding the enemy or being found.
03:48The Battle of the Atlantic was the most important battle of World War II, the most fundamental battle.
03:53Germany needed to win the Battle of the Atlantic because it was the only way that it was going to
03:58be able to destroy Great Britain.
04:02Following Germany's defeat in World War I, the Allied nations were eager to ensure that carnage of such bloody magnitude
04:09would never happen again.
04:12The war to end all wars would be the last.
04:19To ensure peace, the Allies subjected Germany to the strict Treaty of Versailles.
04:26This agreement severely limited weapons production.
04:30The Germans attempted to circumvent these restrictions by establishing shell companies in Holland
04:36and by developing treaties with the Soviet Union.
04:42In the Treaty of Versailles, it was prohibited for Germany to build aircraft and submarines
04:49because the Germans had great experience in submarine building in the First World War.
04:54And they constructed some submarines for Finland, for Sweden, for the Netherlands, for Turkey, and also for the Soviet Union.
05:06These agreements allowed Germany to develop technology for battleships and U-boats,
05:11as well as to adopt various strategies instrumental in the Blitzkrieg and radio war.
05:18When Hitler came to power in 1933, he made it fairly clear that he was going to rearm Germany come
05:23what may.
05:25This was a total violation of the Treaty of Versailles, the Allies laid down, they didn't say anything about it,
05:30and Germany continued to rearm.
05:33The Allied nations were exhausted and in disarray.
05:37They'd lost an entire generation to one war.
05:41Surely such devastation could not be repeated.
05:47After World War I, Britain reduced funding for its navy.
05:51A choice was made to manufacture fewer, larger ships.
05:57It was a smaller navy that entered World War II.
06:02The unfortunate reality was that at the outbreak of war, Britain had no more than 200 destroyers available.
06:09And destroyer has many other roles in the navy, quite aside from convoy escort.
06:13So there had to be compromises.
06:15So Britain adopted smaller ships that were much simpler and could be built more quickly.
06:21Churchill at one point referred to the corvettes, which were the most numerous for the early part of the war,
06:26as cheap and nasties.
06:30With the fall of France to the Germans, the British Navy's major ally, the French fleet, became the enemy.
06:37In an effort to help England, the U.S. provided 50 destroyers.
06:41In exchange, Britain provided the U.S. with sites on which to station their military bases,
06:47in Bermuda, Newfoundland, and the British West Indies.
06:52The American destroyers joined the ranks of the convoys that crossed the Atlantic from various North American ports
06:59to Liverpool and Glasgow in Great Britain.
07:05The convoy system was critical for transporting much-needed men and supplies across the North Atlantic.
07:11The principle of the convoy was to sail the merchant ships in a large group of 40 or more,
07:18and to provide a surrounding escort in the form of warships and aircraft.
07:2440 or 50 ships sailing together are not visible at sea from much farther away than a single ship.
07:30The Germans would have maybe one chance to attack.
07:33So instead of sending out 40, 50, or 60 ships independently,
07:37where the Germans would be able to shoot at them like ducks in a barrel,
07:41instead all of the ships would sail together under protection.
07:46Watching the convoys head out to sea was one of the most magnificent sights in all of World War II.
07:53The ships would file out of the harbor and form a line 20 miles long.
07:59They would organize into as many as six short columns, roughly three-quarters of a mile apart.
08:06Generally, six escort ships would be assigned to the convoy.
08:09Two would be stationed ahead of it, one on either flank, and two sweeping around the stern.
08:17From shore, there would be ships as far as the eye could see,
08:21since the perimeter of a convoy could stretch to more than a hundred miles.
08:27When convoys left Nova Scotia, seaplanes of the Royal Canadian Air Force circled
08:32until they reached their maximum range of 400 miles from land.
08:38Then, when the ships approached England, British seaplanes and land-based bombers would meet the convoy,
08:45and patrol above it.
08:48If aircraft were present, the convoys were safe.
08:53World War II submarines are very slow underwater,
08:56and if they are running on the surface and sight an aircraft,
08:58they immediately have to dive, so it wouldn't be sighted by the aircraft.
09:02The convoy would move off into safety.
09:07At the start of the war, it was almost pitiful, the shortage of escorts.
09:13Convoys used to go out with half a dozen escorts, not nearly enough to protect a convoy.
09:19Also, we went out without equipment.
09:22I mean, my first convoy trip, which was a very short one, I'm glad to say,
09:27and not very far, it was along the coast,
09:29but we had a wooden gun,
09:32which could appear to be a real gun through a periscope,
09:35but it was just there to say we're in business.
09:42The escort ships acted as highly effective, well-armed, protective shields to the convoy.
09:48They never sailed a straight course.
09:51Instead, the escort ships swept back and forth in their sectors,
09:56searching for the enemy by sonar and radar.
10:00But radar had difficulty picking up the very low profile of submarines on the surface,
10:05and sonar's maximum range was only about 2,000 meters.
10:10These were not perfect solutions.
10:14Due to the fall of France and increased U-boat activity in the North Atlantic,
10:19Britain tried to perfect and expand the system of shore-based,
10:24high-frequency direction-finding stations,
10:26codenamed Huffduff.
10:29Stations were soon developed in Iceland, Canada, Bermuda, and the Caribbean.
10:36Within time, the Allies found that when a German warship signaled,
10:40it could be detected from three or four different directions,
10:44revealing a relatively accurate location.
10:52Escort-by-air was not ideal.
10:56Bombers and escort aircraft on both sides of the Atlantic
10:59could only fly 400 miles offshore before they had to turn back.
11:04This limited range created an area in the center of the ocean known as the Black Hole.
11:11It was here that the major battles between convoys and U-boats took place,
11:16beyond the prying eyes of Allied aircraft.
11:22A key component of Durnitz's U-boat strategy were the deadly clusters of submarines,
11:28known to the Allies as wolf packs.
11:33At night, Durnitz would deploy as many U-boats as possible on the surface,
11:38allowing swift and almost invisible movement.
11:43If one of them identified a convoy,
11:45it became what was known as a shadower,
11:48hanging back to send signals about the location to Durnitz's headquarters.
11:54The way it was done was,
11:56Durnitz would begin in the fall of 1940
11:59to put his U-boats on patrol in patrol lines,
12:04so the U-boats would be at visibility distance from each other,
12:08say, 30 miles apart.
12:10A typical communication sent to headquarters as an encoded message might read,
12:15we have contacted a convoy at grid number C-12, section 4.
12:22Durnitz had devised a scheme of grids
12:25which would inform the U-boats of a convoy's location.
12:30The speed and range of communication gear was vital in the Atlantic.
12:35The technology was perfected during the interwar years
12:38when Germany committed to a radio-based infrastructure.
12:42From this, all military commands flowed.
12:46Since radio dispatches traveled through the air,
12:49they were vulnerable to interception.
12:52Secret codes had to defy decryption.
12:56Durnitz used radio more than practically any other naval commander
13:01in order to personally lead the U-boat campaign,
13:04to concentrate in a single spot all of the available information,
13:08a very sound principle of war,
13:10and to make sure that each of the individual U-boats
13:14had a fairly full picture and knew exactly what it was to do
13:18based on that full picture.
13:21Germany's total dependence on radio communications
13:24proved to be a deciding factor in the Battle of the Atlantic.
13:30Durnitz realized that the only way in which the U-boats could work effectively
13:34was in concerted action.
13:38He personally commanded all U-boat radio communications
13:42from his headquarters located in the tiny village of Bernal.
13:48Reports from the submarines would contain information on their location,
13:52the convoy's location, and the convoy's speed and direction.
13:58This information would never be sent back to Durnitz unencrypted.
14:03Nor could he direct the submarines without taking security precautions.
14:08Otherwise, the Allies would intercept communications
14:11and react with lethal countermeasures.
14:15Secret communications required an elaborate encoding procedure,
14:20and the Germans were perfecting an encryption technology to perform it.
14:36As the Battle of the Atlantic continued through the summer of 1940,
14:39it was clear that the Allies were in trouble.
14:42Britain was unprepared for the Code War.
14:46Although they knew the importance of reading the German ciphers,
14:49the British had no idea that their own codes were being read.
14:53Code-breaking is a terrifically useful form of intelligence
14:56because it enables you to get the actual very words of the enemy.
15:03It's kind of like sticking your head into the enemy football huddle.
15:08Allied transmissions were regularly decoded by the Germans,
15:11who often discovered the convoy's location
15:14almost at the same time that Allied headquarters did.
15:18The main problem for the British was that they were still relying
15:22on a kind of World War I-era system of communication security,
15:27basically on codebooks,
15:29which they distributed widely through the fleet
15:31and through their own merchant marine and to their Allies.
15:34The Germans could read these codebooks, could reconstruct them,
15:36and so had a good sense of the general disposition of the convoys
15:40and their routes and the composition of the ships
15:42and which were the major targets and so on.
15:45The German code-breaking unit, the B-Dienst,
15:48had been decrypting British naval codes
15:50throughout the early stages of the war.
15:55To conceal and encrypt their own messages,
15:57the German armed forces purchased an electric coding system
16:01known as the Enigma machine.
16:07Developed in Holland in the early 1920s,
16:10Enigma was able to encrypt messages so thoroughly
16:13that the Germans were convinced it was infallible.
16:21Codes were entered into the Enigma machine
16:23using typewriter-like keys.
16:27Pressing any key would produce a different letter in code.
16:32For example, the letter B would appear as an H one time,
16:36an X the next time, and so forth.
16:41The heart of the machine was the wired code wheel.
16:45It was capable of turning 26 times,
16:48which is why a different letter would appear
16:51each time a B was pressed.
16:55But the Enigma had three wheels working together,
16:58allowing 26 to the third power,
17:01or more than 17,000 different combinations for each letter.
17:09In order to decipher the message,
17:11it was essential to have the starting position
17:13or setting for each wheel.
17:18Despite the challenge,
17:19the Poles, working with the French,
17:21had some success breaking the original Enigma.
17:27However, Dönitz intended to make his Kriegsmarine Enigma
17:31even more difficult to decipher.
17:35He remembered an incident from World War I
17:38when a German light cruiser, the Magdeburg,
17:40ran aground in the Baltic Sea.
17:43The Russians, near whose territory this was,
17:47captured this ship
17:48and found in it
17:49the German Navy's secret code book.
17:54The Russians delivered the code books
17:56to the first Lord of the Admiralty
17:58at the time, Winston Churchill.
18:02The British deciphered the books
18:04and read German naval messages
18:06throughout the war.
18:09This intelligence coup
18:11was instrumental to the Allied victory
18:13in World War I.
18:16Churchill echoed these sentiments
18:18in his book,
18:19The World Crisis After the Great War.
18:23When the Germans read this
18:26in Churchill's memoirs,
18:27they realized that
18:29if there were ever going to be another war,
18:31they had to have a system
18:32of secret communications
18:34which would prevent anybody
18:36from using any captured documents.
18:41Upon reading Churchill's history,
18:43Dönitz swore that his Enigma settings
18:45would never be compromised.
18:50So far, he had kept his promise.
18:53Essential to the U-boat strategy
18:55was the use of Enigma
18:57to keep the messages secret.
18:59Therefore, it was almost central
19:01to all of Germany's naval strategy
19:04in whatever war might come.
19:07Bletchley Park was the center
19:08of Britain's code-breaking activity.
19:12Here, people such as Alan Turing,
19:14inventor of the world's first computer,
19:16plied their highly technical
19:17and demanding trade.
19:22The cryptanalysts had succeeded
19:24in breaking the Luftwaffe
19:25and Wehrmacht Enigma codes.
19:30Due to better security,
19:32their Kriegsmarine enigma
19:33was still a frustrating mystery to them.
19:37The Navy's use of it
19:39was more complicated
19:40than the Air Force's use of it.
19:42Their signaling discipline
19:44was superb.
19:48They had special extra features
19:51which our boffins led by Turing
19:56could not, could not get into.
19:59Though we had this sophisticated machinery
20:01which was reading the Air Force,
20:03we could not get into the Navy.
20:07So early on in the war,
20:09and one of the reasons
20:10that Dönitz had great success
20:12in 1940 and early 1941,
20:14the so-called first happy time
20:17of the U-boat commanders,
20:18was that they had a great advantage
20:20in the intelligence war
20:21and that they were able to read
20:22a significant proportion
20:24of the convoy signals
20:25in time to get U-boats
20:27into a position
20:28to take advantage of.
20:32Dönitz and his U-boats
20:34reigned supreme.
20:36For the first 18 months of the war,
20:38the undersized U-boat fleet
20:39was able to wreak havoc
20:41with the convoys
20:42crossing the North Atlantic routes.
20:49Monthly Allied convoy losses
20:51ranged from about 160,000 tons
20:53in September of 1939
20:55to about 350,000 tons
20:59a year later.
21:04The British needed
21:05a minimum of 17 million tons
21:08of equipment and supplies
21:09a year to survive,
21:11or about 1.5 million tons
21:14a month.
21:30These losses placed
21:32England's survival
21:33in severe jeopardy.
21:40The Germans could easily
21:42detect the convoys
21:43while the Allies
21:44seemed to be completely
21:45in the dark
21:46when it came to locating
21:47the U-boats.
21:52Dönitz, back in Germany
21:54or as it was
21:55later on in France,
21:57would then order
21:58the U-boats
21:59all to concentrate
22:00on that particular place
22:01and send them around
22:03so that there would be
22:04so many U-boats
22:05the escorts for the convoy
22:06wouldn't be able
22:07to attack them all.
22:09Dönitz's headquarters
22:10would alert every submarine
22:12in the vicinity of a convoy
22:13and order them
22:15to converge silently.
22:21Then Dönitz would wait
22:22until sundown.
22:25As darkness fell,
22:26he would issue
22:27the command to attack.
22:42As many as 10 submarines
22:44would converge on a convoy.
22:53Actually getting in between
22:54the rows of the merchant shipping,
22:56blasting away,
22:58creating total chaos,
23:02absolutely nightmare conditions
23:04because ships would be going down
23:05all over the place.
23:06There'd be dramatic explosions.
23:08These battles continued
23:10as the ships moved ahead,
23:12but the slowest convoys
23:14could make only
23:15six or eight knots.
23:19You get near collisions.
23:21There are men screaming
23:22for help in oil
23:23who are going to die
23:24within a few minutes.
23:25The convoys proved
23:26to be easy prey
23:27for the wolf packs.
23:43Once Germany occupied France,
23:45it lost no time
23:46neutralizing the French fleet
23:47and sent its U-boats
23:49to bases on the Atlantic coast
23:50in the Bay of Biscay.
23:54They were very close
23:55so that the German submarines
23:57had to go only one
23:58or one and a half day
23:59to the operational area
24:01to attack the very weakly
24:04defended convoys at the time
24:05and to use all their torpedoes
24:09and go back to the base
24:10to reload the torpedoes
24:11and go out again.
24:13This move allowed Dönitz
24:15to keep more submarines
24:16at sea longer,
24:17which further empowered
24:19the Kriegsmarine.
24:22Churchill's policy
24:23after the fall of France
24:24was to bring the United States
24:26into the war
24:27by any means necessary.
24:29And one of his tools
24:31in bringing the United States in
24:32was to encourage
24:34naval collaboration.
24:35So right from the fall of France,
24:38the American and the British navies
24:40are talking secretly.
24:43In February of 1940,
24:45during a commando raid
24:46on the German trawler Krebs,
24:48the crew of the British destroyer Somali
24:50managed to retrieve
24:51the Kriegsmarine Enigma settings
24:53for that month.
24:56Once the information arrived
24:58at Bletchley Park
24:59and was placed in Turing's hands,
25:01it led to a tremendous number
25:03of solutions.
25:07Needless to say,
25:08Turing wanted more settings.
25:11Harry Hinsley started to devise
25:13a method to retrieve them.
25:17Germans kept two little trawlers
25:20on station in the Arctic.
25:22One off Greenland,
25:23one off Northern Iceland.
25:26For weather reporting,
25:27they had the Enigma.
25:29Believe it or not.
25:31Hinsley knew that if they were at sea
25:33for seven weeks,
25:34the trawlers would have to have
25:35more than one month
25:36setting sheets on board.
25:39The current setting sheet
25:40would be on the operator's desk.
25:43Next to his desk
25:45was a bucket of water.
25:47If the trawler was boarded,
25:49the operator would simply
25:50drop the sheet in the bucket,
25:51and the vital codes
25:52would wash away.
25:54But the next month's settings
25:55were kept in the safe.
26:00The British planned
26:01to raid a trawler,
26:02seize the papers,
26:03and get out,
26:03what they called
26:04a cutting operation.
26:08On the 7th of May, 1941,
26:11they targeted
26:11the weather trawler
26:12Munchen
26:13between Iceland and Norway.
26:18I was the center
26:19of the spider's web.
26:22I had a man
26:23from the Admiralty
26:23come to my section,
26:25to my room,
26:26you see,
26:27and we rehearsed
26:28what I guessed
26:28he would find
26:29when he got there,
26:30you see.
26:32I was the chap
26:33telling them
26:33what to look for
26:34and where to go for it,
26:36and so on.
26:37Of course,
26:37the Navy did
26:38a beautiful job.
26:40The raid
26:41was a glorious success.
26:43Later,
26:44they repeated
26:44the operation
26:45on another weather ship,
26:46the Lohenberg.
26:50And these poor little ships,
26:52just little trawlers
26:53cruising along,
26:54and then suddenly
26:55over the horizon
26:56would come
26:56a British cruiser
26:58supported by
26:59two super destroyers
27:00swooping in,
27:02and they moved fast.
27:03They were coming in
27:0440 kilometers an hour
27:05again
27:06in order to
27:07capture the ship
27:08before the crew
27:09could destroy
27:10their coding books.
27:13Two days
27:13after the raid
27:14on the Munchen,
27:15a convoy battle
27:16took place
27:16on the other side
27:17of Iceland.
27:20The U-110
27:21was forced
27:21to the surface
27:22during the fight.
27:25Joe Baker Cresswell
27:27was the commander
27:27of the closest
27:28Allied ship.
27:32And he set course
27:34immediately
27:34to ram this U-boat
27:36and sink it
27:36and send it
27:37to the bottom.
27:38As he headed
27:39toward the hapless
27:40U-110,
27:41a thought
27:42flashed
27:42into Baker Cresswell's
27:43mind,
27:44the story
27:45of the saved
27:45codebooks
27:46of the Magdeburg.
27:50So he called
27:51out full stop.
27:53The ship
27:53came to a full stop
27:55and he sent
27:56over then
27:57rapidly
27:57a boarding party.
28:00The U-boat
28:01survivors
28:01were quickly
28:02rescued
28:02and taken below.
28:05Then
28:05Sub-Lieutenant
28:06David Baum
28:07climbed down
28:08a lower
28:08conning tower.
28:10Once he was
28:11inside the U-110
28:12he discovered
28:14that all
28:14was silent.
28:17Except for
28:18some kind
28:19of a hissing
28:19sound
28:20and the noise
28:20of the motors
28:21maybe ticking over,
28:22he managed to get
28:23not just the
28:24Enigma machine
28:25but had
28:25some of the
28:26keying documents.
28:30The U-110 papers
28:31were quickly sent
28:32to Bletchley Park.
28:35These were the final
28:37pieces of the
28:37naval Enigma puzzle.
28:41With the captured
28:42papers from the
28:43Munchen,
28:44the Lorenberg
28:44and the U-110,
28:46Bletchley Park
28:46was finally able
28:48to crack the
28:48Craig's Marines
28:49Enigma machine.
28:54This was the moment
28:55the Allies had been
28:56waiting for.
28:59Now they could
29:00locate the U-boat
29:00packs and more
29:01importantly,
29:02know where they
29:03were going
29:03and how to
29:04avoid them.
29:08Convoys could be
29:09rerouted and made
29:10invisible to the
29:10German fleet.
29:13The Allies were
29:14back in the Battle
29:15of the Atlantic.
29:18With this
29:19information,
29:20the British
29:21were able to
29:22route convoys
29:23clear of the
29:25concentrations of
29:26German submarines.
29:28We were steered
29:29towards a convoy
29:30and when we got
29:31there, the convoy
29:32wasn't there.
29:33In other words,
29:34somebody apparently
29:35expected us to
29:36appear.
29:39We were attacked
29:40in the middle of
29:41the night by
29:42airplanes,
29:44which in our
29:45opinion couldn't
29:45see us somehow,
29:47but they knew
29:47we were there.
29:48And so somehow
29:49we had the feeling
29:50that the enemy
29:51had some means
29:52of locating
29:53of where we were.
29:56Dönitz's victories
29:57dropped from
29:58325,000 tons
30:00of cargo in
30:00May 1941
30:02to 90,000 tons
30:04by July.
30:07Despite this
30:08enormous decrease,
30:09the Craig's Marines'
30:10faith in the
30:11Enigma machine
30:11did not waver.
30:14They could not
30:15imagine that the
30:16code had been
30:17broken.
30:19Dönitz convened
30:20committees to
30:21review all possible
30:22ways in which the
30:23British were
30:23discovering the
30:24locations of his
30:25submarines.
30:28Blame was usually
30:29attributed to
30:29French spies or
30:31British spies in
30:32French ports
30:33where the U-boats
30:34were based.
30:37We were, at that
30:39time, totally
30:40convinced that
30:41nothing could
30:42break that
30:43code, even if
30:44somebody would
30:45receive it and
30:46try to decode it.
30:47Only after the
30:48war, of course,
30:49did we find out
30:50that we were very
30:50wrong with this
30:51kind of attitude.
30:52The irony is, by the
30:54end of the war,
30:55virtually every
30:56Enigma code was
30:57being read as
30:58fast as the
30:59Germans themselves,
31:00the recipients,
31:01were reading it.
31:05The Allies saved
31:07hundreds of
31:07thousands of
31:08tons of
31:09merchant marine
31:09ships carrying
31:10men and material
31:11to Great Britain.
31:20Dönitz's
31:21dependency on
31:22radio transmissions,
31:23which had led to
31:24so many successes
31:25in the early
31:26months of the
31:26war, was
31:27proving to be
31:28his downfall.
31:33Then, in December
31:341941, the
31:36high seas battle
31:37took a new
31:37turn.
31:45On the 7th of
31:46December 1941,
31:48Japan attacked
31:48Pearl Harbor, and
31:50the United States
31:51declared war on
31:52Japan.
31:53That since the
31:54unprovoked and
31:56dastardly attack
31:58by Japan on
32:01Sunday, December
32:037th, 1941, a
32:07state of war has
32:11existed.
32:17Hitler promptly
32:19declared war on
32:20America.
32:21Churchill's prayers
32:22of bringing
32:22America's wealth,
32:23resources, and
32:25technological
32:25expertise into
32:26the war were
32:28answered.
32:28Then, when the
32:29United States
32:29comes into the
32:30war in December
32:32of 1941, the
32:33curve just takes
32:34off.
32:37And as the
32:38U.S.
32:39industrial machine
32:40mass produces
32:41ships, using
32:42mass production
32:43techniques for the
32:43first time on a
32:44grand scale, you
32:45can see that
32:46Germany's days in
32:47any material sense
32:48are numbered.
33:06Having found no
33:07convoys all the
33:09way through the
33:09second half of
33:101941, and having
33:12declared war on
33:13America, Dornitz
33:17says, the best
33:19thing to do is to
33:19send all the
33:20boats to the
33:21American seaboard.
33:23For two years,
33:25American ships had
33:26been traveling
33:26unescorted along the
33:28Atlantic coast.
33:38Now that the
33:39United States was
33:40in the war, merchant
33:41ships on the
33:42east coast were
33:43fair game for the
33:44U-boats on the
33:45prowl.
33:45U-boats on the
34:00So he had them all
34:01strung out from the
34:02St. Lawrence down to
34:03the Caribbean, where
34:04there was no convoy
34:06system, where all the
34:07lights were still on,
34:08and the boats just
34:09sitting off New York
34:11Harbor, or the St.
34:12Lawrence entrance, or
34:13war among the islands
34:14in the Caribbean, and
34:16shooting the ships as
34:17they came along, in
34:17full electric light,
34:19you see.
34:21Dornitz's U-boats
34:23sank 137 ships, or
34:25about 828,000 tons of
34:28supplies, a
34:29catastrophic number.
34:31Then another major
34:32setback for the Allies
34:33occurred.
34:35Dornitz upped the
34:37difficulty of solution
34:39by adding later on
34:41another wheel, so
34:42instead of three
34:43wheels, there were
34:43four wheels in the
34:45Enigma, and made a
34:46number of other
34:46technical complications
34:48to this.
34:50The fourth rotor
34:51added a tremendous
34:52number of new
34:53possibilities, and
34:54made decryption of
34:55the Krieg's marine
34:56signals almost
34:57impossible.
35:00But where this was
35:02somewhat positive for
35:04the Allies is that
35:06their convoys doing
35:07the absolutely critical
35:09transport across the
35:11North Atlantic were not
35:12coming under attack, so
35:14that the German
35:16intelligence advantage was
35:17not as critical as it
35:19might have been during the
35:20first half of 1942.
35:23America's entry into the
35:24war was timely for Bletchley
35:26Park.
35:27To solve the fourth
35:28world, Alan Turing required
35:30enormous decryption
35:32machines called bombs, which
35:34were far beyond the
35:35resources of the British.
35:36British.
35:38Bletchley Park welcomed the
35:39Americans into the process by
35:41sharing more intelligence
35:42information.
35:44In turn, the U.S.
35:46government began to build
35:47Turing's massive calculating
35:49machines to tackle the four-rotor
35:52combination.
35:58Without current Enigma code
36:00settings, it became clear that
36:01the Allies required a more
36:03robust anti-submarine strategy.
36:06The Air Force was marshaled to
36:08the defense.
36:11One of the most important aspects of
36:13this development has been the
36:15construction of air bases on the
36:17periphery of North America and
36:19way out on the North Atlantic
36:21Islands, in Iceland and even in
36:24Greenland.
36:25And the Allies used these bases in
36:27order to operate bombing
36:29aircraft to provide aerial
36:31protection over convoys.
36:34Durnis was back in the high seas of
36:36the North Atlantic.
36:37The convoys had been blinded and
36:40the Allies were suffering heavy
36:41losses.
36:43Then Bletchley Park got a break.
36:47We got back into the U-boat
36:50Enigma in December 1942.
36:54We discovered that when they were
36:56using, transmitting these short
36:57signals, either to report the
36:59weather or to report operational
37:02material, they only used the three
37:05wheels of the new machine, because
37:07they were three-letter signals, you
37:10see.
37:11And we could break the three wheels.
37:14But we captured a U-boat in the
37:18Mediterranean, near the Red Sea, near
37:21the Suez Canal.
37:24U-559 had been trapped in the
37:26southeast Mediterranean by the Petard,
37:28a British Navy destroyer.
37:32Its commander, Mark Thornton, was an
37:34energetic officer who craved the
37:36excitement often missing in a naval
37:38patrol.
37:40This time he found it.
37:43The U-559, starved of oxygen, rose to
37:46the surface.
37:49The U-boat's crew immediately
37:50abandoned ship, and Thornton sent a
37:53small boarding party from the Petard.
37:57The crucial documents were retrieved by
37:59Anthony Fasson, a popular officer aboard
38:02the Petard, and Colin Glazier, a young
38:04seaman.
38:10A third sailor took the documents back to
38:12the Petard.
38:14Then Fasson and Glazier went back down to
38:17look for more secret papers.
38:19But earlier gunfire from the Petard had
38:22left holes in the U-559.
38:25Water was pouring in, and U-559 began to
38:29sink.
38:31The people outside shouted down to these
38:34two men who were down there, you'd better
38:36come up, you'd better come up.
38:38But these men started to climb up the
38:40ladder, but suddenly the U-559 went down
38:44very fast, too much water was coming in
38:46the conning tower, and these men went down
38:49with the ship.
38:51Thanks to their valiant sacrifice, British
38:54codebreakers were able to decipher Enigma
38:56messages once again, and thousands of Allied
38:59lives were saved.
39:03Fasson and Glazier were posthumously awarded
39:06the George Cross.
39:13The Allied mariners often faced a fierce North
39:16Atlantic, which could be as dangerous as the
39:18German U-boats lurking beneath the surface.
39:25Winter gales were simply unending.
39:28One came in right after the other, and water
39:31came over green over the bridge.
39:34And if you weren't dressed properly, it was
39:36misery.
39:42It was very hard living, particularly down in
39:45the mess decks, which were small, comparatively
39:47small space, considering the number of men that
39:50were in it.
39:51And the place just reeked of vomit and sweat and
39:54there's lack of air.
39:56You couldn't have anything open, of course, and not
39:59nearly enough air came through the louvers.
40:01It was an extremely difficult condition.
40:06When we compared our life with that of others, like
40:10the ones in the trenches, then we could say, we have it so
40:15much better than anybody else.
40:16We had three meals a day.
40:18We were dry.
40:19We had warm bucks.
40:20We ate from tables with linen on it.
40:24And we were not nearly suffering as much as everybody
40:30else, especially our opponents up on the surface, the
40:33corvettes and the frigates of the Allies.
40:37We sometimes really felt very sorry for them to have to fight
40:40against the Atlantic itself.
40:44These feelings of empathy for the Allies didn't last long as
40:48the Germans continued to decrypt their codes and hammer the
40:51convoys.
40:57By autumn 1942, American single ships were traveling in
41:01convoy.
41:04The Allies developed a top-secret interlocking coastal
41:07convoy system linking South America to the American East
41:10Coast and to the Canadian ports of Halifax and Sydney.
41:15As the war progressed, the Battle of the Atlantic became a
41:19higher priority.
41:21More Allied ships and resources were deployed.
41:24The talent of the Royal Navy was put on the offensive in the
41:27form of the support groups.
41:31Designed to counter Dönitz's wolf packs, the support groups
41:34were an elite fleet of well-equipped, brilliantly
41:37skippered ships that scoured the Mid-Atlantic.
41:42These were groups of the most powerful anti-submarine ships,
41:45and there would be four or five very good destroyers or strong
41:50sloops, and also an escort aircraft carrier.
41:52These support groups operated at mid-ocean, and then when word
41:58got out that a convoy was in trouble, the support group would
42:01dash to assist that convoy.
42:08Normally, the escort group of the convoy tried to push submarines
42:12away, or at least keep them underwater, as they sailed on with
42:15their cargo.
42:19The support groups had no convoy to protect, however.
42:25They hunted and killed U-boats.
42:33Whenever a submarine tried to approach a convoy, the support group
42:37attacked using a variety of sophisticated equipment.
42:45Head-throwing mortars, state-of-the-art sonar, radar, and
42:50onboard high-frequency direction-finding systems were all employed.
42:55The support groups played a crucial role in turning the Battle of the
42:59Atlantic to the Allies' favor in May 1943.
43:05You could usually detect the U-boat at about 3,000 yards.
43:10And then the echoes, which went out and made a ping when they hit the target,
43:18whatever it was, and came back, that measured the distance off of the U-boat.
43:24And as you approached, it was under the water, and of course not moving very much.
43:28As it got closer and closer and closer, you knew the time was coming when your depth-charge
43:35crews would be instructed to fire.
43:38We then are subjected to these series of explosions of depth-charges around us.
43:47And I hope for the best that after the next one we're still alive.
43:51This is really quite, I would say, a terrifying experience to sit there, not being able to do
43:58anything but to wait.
44:00What is the effect of the next depth-charge?
44:02If it comes close enough, then the effect is more or less that of a giant sledgehammer
44:09on an immovable object.
44:12The impact does do all kinds of damage inside the boat.
44:16And then, of course, you would be at speed, because you always had to go faster than you
44:22wanted to go, really, because you had to be ahead of your own depth-charge.
44:26Otherwise, you'd be damaged by them.
44:28So this can go on for six hours, 12 hours, and hundreds of depth-charges.
44:37I claim that anybody who says he is not afraid in those situations is a liar.
44:49I claim that he is not afraid in those situations, and I claim that he is not afraid in those
44:50He is forced to abandon attacks on convoys because, in one of the crucial battles, he
44:57sinks 11 merchant ships out of a convoy of 40-odd merchant ships.
45:01It looks like a brilliant success rate.
45:03He lost six submarines in doing that.
45:07If every time you sink a merchant ship or two merchant ships, you lose a submarine, you're
45:11very quickly going to completely lose your submarine force.
45:16Durnitz was now effectively losing a submarine for every merchant ship he sank.
45:23The United States was building so many ships that the Germans couldn't sink as many as
45:30the Allies were building, sometimes two or three a day.
45:32And in the end, it was America's shipbuilding capability that really won the Battle of the
45:38Atlantic.
45:41The Allies continued to use their industrial and technological might as well as their intelligence
45:46breakthroughs to their advantage.
45:54Longer range Royal Air Force and North American Allied aircraft also managed to fill the treacherous
46:00black hole above the middle of the North Atlantic.
46:06The value of an aircraft is that it would surprise the submarine while a submarine was on the
46:11surface.
46:12And the aircraft could do a very fast dive, a virtually dive-bomb the submarine, and then
46:17try to place the bombs across it.
46:21By 1942, more sophisticated aircraft were capable of patrolling at altitudes of up to 5,000 feet.
46:31The moment they saw a submarine, they would plunge from 5,000 feet to 50 feet right across the
46:38hull of the submarine and drop a stick, a timed stick.
46:42They called it a stick of four or six depth chariots, boom, boom, boom, boom, and hoping
46:48that two of them would be close enough to the hull of the submarine to blow it up.
46:53We attracted them to convoys, went for them.
47:00We knew their refueling points, where a mothership would come in a distant part of the ocean,
47:08kill them off.
47:09They had a miserable time.
47:18On the 21st of September, 1943, Winston Churchill had a most satisfying announcement to make.
47:26He reported that not one merchant ship had been lost to enemy action in the North Atlantic
47:31in the past three months.
47:35Britain cheered.
47:39Britain cheered.
47:39But the war continued to rage on land and at sea.
47:45Even until the end of the war, U-boats lurked off the American coast and throughout the Atlantic.
47:52But with the help of ULTRA, the code name for the secret information Bletchley Park was
47:57able to provide, the Allies finally won the Battle of the Atlantic.
48:05I myself, for the last days before we surrendered, was listening to the Voice of America on our
48:11radio and was being told that the Russians are now fighting about two blocks away from
48:15where my mother lived in Berlin.
48:17And this, of course, was some very, very unpleasant realization of what was going on over there.
48:23In other words, one worried about what was happening in Germany.
48:25On the other hand, the fact that what had finally survived, when so few actually did, was a tremendous relief
48:33somehow.
48:38The key to ULTRA's contribution, I think, in the Battle of the Atlantic was that ultimately
48:43they were able to control the U-boat threat in time to allow the buildup of preparations
48:49for the Normandy invasion in 1944.
48:52It was, really, a supreme intelligence weapon, of a kind that no powers had before and probably
49:00no power had since that time.
49:03The purpose of intelligence is to optimize a commander's resources.
49:09And ULTRA enabled him to do this.
49:11And by optimizing resources, we were able to shorten the war.
49:16And by shortening the war, we saved treasure, we saved lives.
49:20That was the ultimate effect of ULTRA in World War II.
49:25The duel in the Atlantic was the longest battle of World War II.
49:34More than 700 U-boats and over 25,000 German submariners lost their lives, while the Allies
49:43sacrificed 2,600 ships and 80,000 soldiers and seamen for their crucial cause.
49:51Yet, the Battle of the Atlantic was a battle of secrets.
49:56Dernitz's major advantage proved to be his Achilles' heel.
50:00By sending his crucial secret messages through the air and gambling on the infallibility of
50:06the Enigma machine, he unwittingly threw victory to the Allies.
50:11The key to the Enigma codes was the key to victory.
50:20The Battle of the Aceries