Full transcript
0:00In the spring of 1941, Britain was in the midst of an Atlantic crisis.
0:05German submarine, surface and air attacks
0:08were sinking merchant ships by the hundred.
0:12If those losses continued, Britain could lose a quarter of its fleet
0:16within the year and might just be starved out of the war.
0:20Yet, just a few years later, everything had changed.
0:25By 1943, German U-boats had gone from predator
0:29to prey, as the Allies took full control of Atlantic Ocean.
0:33So how did they do it?
0:35The Battle of the Atlantic was a race of advanced technology.
0:40Skilled German U-Boat captains, coordinated by the famous Enigma system,
0:45hunted down British ships often at will.
0:49The Royal Navy needed to step up.
0:52Innovations in escort vessels, SONAR and RADAR,
0:56and British aircraft, were vital to defeat the U-Boat menace.
1:00This is the story of the race to victory in the Battle of the Atlantic.
1:13Throughout the war,
1:15German U-Boats would sink millions of tons of shipping,
1:18especially along the crucial North America Route in the North Atlantic.
1:23In the display behind me, each ship represents five allied vessels
1:28that were sunk or damaged by German submarines.
1:32It is a visual representation of the enormity
1:36of Allied losses in the Atlantic.
1:39June 1942 was the worst month for the Allies
1:43with the loss of 830,000 tons of shipping.
1:47But we can see that by 1943, this number had dropped significantly.
1:52Before the Second World War
1:56Britain was one the world’s great powers.
1:59It had a sprawling empire and the world’s largest navy.
2:03However, Britain also had a major weakness.
2:07As an island nation, Britain
2:10relied on merchant ships for crucial supplies,
2:13almost all of which had to pass through the Atlantic The German Navy understood
2:19that breaking this chain had the potential to cripple Britain and their war effort.
2:24And whilst the German surface fleet was small,
2:27their submarines were some of the most advanced in the world.
2:31On the eve of war in 1939,
2:35the German Navy were prepared to fight a ‘war of attrition’ against the British.
2:40German Admirals Erich Raeder, Head of Naval Command, and Karl Dönitz,
2:45commander of the U-boat arm, had come of age
2:48during the ‘unrestricted’ submarine warfare of the First World War.
2:53Despite Adolf Hitler’s wish for a short, quick war,
2:56Raeder understood this would be a total war.
3:00Although Hitler aspired to a grand surface fleet to rival the Royal Navy,
3:04Dönitz thought resources should be focussed on submarines
3:08to destroy Britain’s merchant fleet.
3:11In this war of attrition, Dönitz considered every enemy ship
3:15a legitimate target.
3:16Germany began the Battle of the Atlantic with two key weapons.
3:21The Mark VII and Mark IX U-boats.
3:24The Mark VII medium range submarine was the workhorse of the German Navy.
3:29With 14 compressed air or electric torpedoes,
3:32and an operational range of 6,500 miles, nearly seven
3:36hundred of these formidable submarines were built during the Second World War.
3:41The larger, more powerful Mark
3:44IX U-boat was armed with 22 torpedoes,
3:47and had a global range to fight anywhere in the world.
3:51Able to sneak
3:52up on an enemy ship, underwater, undetected,
3:55before unleashing a devastating volley of torpedoes,
3:58both U-Boats were a truly terrifying prospect
4:02to Allied sailors, but they weren’t completely invincible.
4:06This massive aircraft is the Short Sunderland flying boat.
4:11They were introduced by the Royal Air Force Coastal Command in 1938,
4:15a year prior to the outbreak of the Second World War.
4:19The Sunderland is a long-range Maritime
4:21Patrol aircraft, designed to operate at sea.
4:24It flew as a convoy escort, as an anti-submarine
4:28and shipping aircraft, and for search and rescue.
4:31The Sunderland would prove to be one of the key weapons
4:34of the Battle of the Atlantic.
4:35Key to the defence of British merchant shipping was to group ships in convoy,
4:40escorted by long range aircraft and small
4:43anti-submarine ‘escort’ vessels.
4:47The Atlantic covers over 100 million square kilometres.
4:50In such a vast space, finding a convoy was harder than finding a single ship,
4:56as there were fewer targets,
4:58and attacking U-boats could be attacked by the escorting warships.
5:09At the
5:09beginning of the war, the British attempted to hem
5:13the German U-Boats in and stop them reaching the Atlantic.
5:16Allied vessels blockaded German ports while RAF Coastal
5:20Command patrolled the English Channel and the North Sea.
5:23But despite these defences, on the 3rd of September 1939,
5:27the SS Athenia – a British passenger liner - became the first Allied ship
5:32to be sunk in the Atlantic by a German U-boat.
5:35This marked the beginning of the Battle of the Atlantic.
5:38From September 1939 to May 1940, over 300
5:45Allied ships were sunk in the Atlantic, to only 24 U-boats lost.
5:49And things were about to get even worse...
5:57The conquering armies
5:58now stood on the shores of the Atlantic.
6:04France had fallen, and Germany
6:06now had direct access to the Atlantic along the French west coast.
6:11German U-boats could now attack convoys even further away
6:14and spend much more time at sea than before.
6:18This had a devastating impact on Allied shipping,
6:21and immense losses continued through to early 1941.
6:25Among German submariners, this period would become known
6:29as the ‘First Happy Time’.
6:31Meanwhile Britain had lost a huge amount of military equipment in France
6:36and was becoming increasingly depended on American Lend Lease support,
6:39which made the Battle of the Atlantic an even more important theatre of war.
6:44But it was a battle the British were losing.
6:47They could only build 1.25m tons of shipping each year,
6:51but if the losses for March, April 1941 continued,
6:55they were set to lose 7.3m tons
6:58by the end of the year A solution was needed and fast.
7:03Asdic,
7:04later known as sonar, was a secret device for locating
7:08submerged submarines by using sound waves.
7:12It consisted of an electronic sound transmitter and receiver.
7:16This was housed in a metal dome beneath the ship’s hull.
7:20High-frequency soundwaves were sent out
7:22and bounced back as an audible ping when they hit a submarine.
7:27This stopwatch was used to time the pings heard
7:30when a U-boat was detected by ASDIC.
7:33The number of seconds between pings
7:35corresponds to a distance shown on the stopwatch,
7:39and the pitch of the echo revealed if it was approaching
7:42or moving away.
7:45That sound on the deck detected
7:47the engines of a submarine.
7:51Definitely a sub, sir.
7:52Quite close to us.
7:55That's it.
7:56Keep after it.
7:57Swing right over and start blasting.
8:00There goes the underwater blast.
8:05Despite these
8:06advantages, a highly trained operator was required
8:09to use the equipment effectively, and even then, the system
8:13initially proved useless when U-boats attacked on the surface at night.
8:18However, as the war progressed, the technology improved.
8:22Making ASDIC easier to use and improving its success rate.
8:26The feared U-boats had now lost their most important weapon
8:29– the element of surprise.
8:41By March 1941,
8:43the campaign had become a focal point of the entire war.
8:47Churchill publicly named the campaign ‘The Battle of the Atlantic’
8:51and created a new War Cabinet Sub-committee to address the issues
8:54with the losses in shipping.
8:56Meanwhile, the Royal Navy began to bring in extra maritime patrol aircraft.
9:01These were fitted with long-range radar,
9:04to detect any U-Boats operating on the surface,
9:08as well as automatic machine guns, bombs and depth charges to destroy them.
9:13British aircraft such as the Short Sunderland,
9:16were used alongside US built aircraft including the Lockheed Hudson,
9:21Consolidated Catalina flying boat, and the Consolidated Liberator.
9:25Along with new Coastal Command bases, including one in Iceland,
9:30these pushed the U-boats into an area where Allied aircraft
9:33could not reach them, this ‘mid-Atlantic gap’ was effectively
9:37a safe zone for U-Boats, and became known as ‘the black pit’ to Atlantic convoys.
9:44The posters on display here
9:45were used to remind the British public of the importance of the battle
9:49going on in the Atlantic, whilst in Germany, aerial propaganda
9:54leaflets such as these were dropped by the Allies.
9:57They show U-boat service leading to a cold grave – and they weren’t wrong, once
10:03a U-boat was sunk the chances of survival for its crew were incredibly slim.
10:08In May 1941, the Royal Navy successfully sank
10:12the German Battleship Bismarck after a prolonged chase the night before.
10:17British ships rescued 110 survivors
10:19but had to withdraw due to a U-boat sighting.
10:22This left hundreds more German sailors to their fate.
10:27The sinking of the Bismarck was an enormous blow to German morale,
10:30and for Hitler it validated his fears of facing the Royal Navy in open warfare.
10:37But for the
10:37British, the sinking, combined with an increase in escort vessels
10:41and the growing effectiveness of RAF Coastal Command,
10:44gave the second half of 1941 a much more positive outlook.
10:49But that optimism would be short lived...
11:01In December 1941 the United States joined the war,
11:05and the Kriegsmarine immediately dispatched U-boats to the Americas.
11:10The Germans opened unrestricted submarine warfare.
11:17The US were not yet ready to deal with U-boats and what followed
11:21was an open season on Allied shipping from the East coast to the Carribean.
11:26This was the ‘Second Happy Time’ between January and August 1942.
11:31868 ships totalling
11:343.1 million tons of shipping were lost,
11:37against only 42 German U-Boats.
11:43Back in Britain,
11:44the Admiralty were pushing for an increased allocation
11:47of long-range aircraft, but despite the skyrocketing losses in shipping,
11:51Churchill rejected these proposals.
11:54He thought it was more important to take the fight directly to Germany,
11:58and build up the RAF’s bomber force, rather than Coastal Command.
12:01American shipbuilding efforts were beginning to increase, and Churchill
12:05believed they would soon be producing enough ships to replace British losses.
12:10This would soon be proven not to be the case.
12:12By now the United States had managed to set up several
12:17new air bases in South America, the Carribean and Greenland forcing
12:21the U-Boats to return to the familiar hunting grounds of the mid-Atlantic gap.
12:26It was here that the tide of the battle began to turn.
12:29By 1943 Allied
12:32countermeasures were beginning to take their toll.
12:36That year 284 U-boats were sunk,
12:39in comparison to only 27 in 1940.
12:43The Germans developed new countermeasures of their own to try and stay in the game.
12:48Technology such as ‘BOLD’ decoys, which confused British ASDIC
12:53systems, ‘Alberich’ anti-sonar coating, which reduced ASDIC effectiveness,
12:58and ‘Schnorkel’ which allowed U-Boats to stay submerged for longer.
13:03U-boats were powered by diesel-electric engines,
13:07which required them to remain on the surface for long periods,
13:11drawing in air for the diesel engines. When submerged,
13:15they operated by
13:16battery power, but this only had a short range.
13:20‘Schnorkel’ was a long-extended pipe to the surface,
13:23that could draw down air for the diesel engines when submerged.
13:27However, all of these innovations had limited effectiveness,
13:32when set against experienced British ASDIC operators, or when operating
13:37at a reduced depth due to the limitations of the ‘Schnorkel’ device.
13:41Erich (er-ich) Raeder resigned as Commander in chief of the German Navy
13:46in January 1943 and was replaced by Karl Dönitz.
13:50The German Submarine fleet reached its peak in early 1943,
13:54with around 240 U-Boats in operation
13:57and more than 100 of those out to sea at any one time.
14:00But this was also a key turning point for the Allies,
14:04who cracked the Enigma code at the end of 1942.
14:08Now able to intercept and decipher German messages,
14:11the Allies were able to divert convoys away from U-Boat wolfpacks,
14:15whilst going on the offensive to hunt down U-Boats in known locations.
14:20RAF Coastal Command also began launching a series of attacks
14:24into the Bay of Biscay from February 1943.
14:27The idea was to destroy German U-Boats
14:30leaving France before they could reach the Atlantic.
14:33The effectiveness of these missions is up for debate, Coastal Command suffered
14:37significant losses because the bay was in range of Luftwaffe fighters.
14:42But the missions did successfully put additional pressure on the German U-Boats.
14:48The final piece of the puzzle that turned the tide in
14:51the Atlantic, were Allied advancements in Aircraft and weapons technology.
14:55The Liberator was of particular importance
14:59as they were able to plug the ‘Mid-Atlantic air gap,
15:03when the ‘Very Long-Range’ variant was introduced in May 1943.
15:08This was a variant of the B24 Liberator strategic bomber,
15:13similar to this aircraft on display at IWM Duxford.
15:17This particular aircraft was manufactured
15:20by the Ford Motor company in Detroit in March 1945.
15:24Liberators were the most heavily produced aircraft of the Second World War,
15:29with over 19,000 built in the US, and serving with the USAAF, US
15:35Navy, RAF and allied air forces around the world.
15:39The final nail in the coffin for German U-boats was the introduction
15:44of the British ‘Hedgehog’ and ‘Squid’ devices in 1943.
15:49The ‘Squid’ fired a salvo of three-six large 12-inch mortar
15:53bombs over its target.
15:55A direct hit would almost always sink a U-boat.
15:58The “Hedgehog”, like the one on display behind me, was a mortar
16:03which could fire a salvo of 24 bombs
16:06in a circular pattern ahead of the ship.
16:09This system was much more accurate than stern deployed
16:12depth charges and covered a wider area of damage.
16:16The Atlantic Gap was now effectively closed by Allied Aircraft,
16:21and escort vessels were armed
16:23with the tools to reliably defend against attacking wolfpacks.
16:26Things got even worse for the Kriegsmarine
16:28when Portugal offered an airbase in the Azores to the Allies, further
16:33increasing their command over the Atlantic.
16:35Black May of 1943, saw 34 U-boats
16:40sunk and so, on the 24th Karl Donitz decided to call his forces back.
16:46They would return to the ocean, but their impact would never be the same.
16:59By summer
16:591943, the combination of advanced escort vessels,
17:04ASDIC/SONAR, long-range patrol aircraft,
17:08and weapons such as Hedgehog and Squid,
17:11had finally defeated the U-boat threat.
17:14The vital sea lanes between Britain and North America were now fully open.
17:19This was to prove crucial for the D-Day invasion,
17:22and liberation of Europe over the next two years.
17:26The U-boat threat wasn’t entirely diminished.
17:29By 1945 the German Navy had developed
17:32the advanced, fully submergible, Type XXI ‘Electro-boat’.
17:37But it was all too little, too late.
17:40Over 1,300 Allied ships were sunk in the Atlantic in 1942,
17:46but that number more than halved in 1943,
17:49and halved again in 1944.
17:52241 U-Boats were sunk
17:54in 1943, more than all previous years combined,
17:58and these numbers would continue to the end of the war.
18:02The Battle of the Atlantic was the longest campaign
18:04of the Second World War, running continuously from the first days,
18:09right up until the defeat of Nazi Germany 6 years later.
18:133 out of every 5 German Submariners would die over the course of the war,
18:18along with many more sailors, merchants,
18:21and civilians in this most decisive of battles.