0:00:03 > 0:00:06Londonderry is famous for a remarkable siege.
0:00:07 > 0:00:10But there's an extraordinary time in the city's more recent past
0:00:10 > 0:00:13that's been forgotten.
0:00:13 > 0:00:15The years when Derry was at the centre of World War II's
0:00:15 > 0:00:19longest and most decisive battle.
0:00:19 > 0:00:22The Battle of the Atlantic.
0:00:22 > 0:00:25To reveal this story, we begin not in the city,
0:00:25 > 0:00:27but on the waters off its coast.
0:00:30 > 0:00:34Out there, on the horizon, hidden deep beneath the waves,
0:00:34 > 0:00:37lie hundreds of forgotten shipwrecks.
0:00:37 > 0:00:41Together, they tell the story of an extraordinary conflict.
0:00:41 > 0:00:43It lasted nearly six years.
0:00:43 > 0:00:47100,000 men died and 4,000 ships were sunk.
0:00:49 > 0:00:52Wrecks from the battles still litter the seabed here,
0:00:52 > 0:00:56lost, forgotten and out of reach, until now.
0:00:57 > 0:01:01One underwater explorer has compiled a unique map.
0:01:01 > 0:01:05It charts the lost wrecks of the Battle of the Atlantic.
0:01:05 > 0:01:09Now he and a team of expert divers are going in search of them,
0:01:09 > 0:01:11to uncover the lost stories of the battle.
0:01:13 > 0:01:15All hatches are closed.
0:01:15 > 0:01:19There's an open locker with live ammunition in it.
0:01:19 > 0:01:23What they discover, will restore Derry's lost place in the history
0:01:23 > 0:01:25of World War II.
0:01:25 > 0:01:27The Battle of the Atlantic could not have been won
0:01:27 > 0:01:32if the bases on the Foyle had not been available to the Allies.
0:01:32 > 0:01:35The residents of Derry had been on the front line
0:01:35 > 0:01:39so this is an opportunity for them to see the U-boat gotten rid of.
0:01:39 > 0:01:43And over 70 years later, the generation who witnessed
0:01:43 > 0:01:48first-hand this extraordinary time in Derry, share their experiences.
0:01:48 > 0:01:53He was so badly injured. His body was covered in splinters.
0:01:53 > 0:01:57To me, this was part of the U-boat coming alive, you know?
0:01:57 > 0:02:00The dancing and the courting and coming home with boys.
0:02:02 > 0:02:06I feel like I want to take him out of the screen and give him a hug.
0:02:06 > 0:02:09All you think about is what the people back home will think
0:02:09 > 0:02:12when they know I'm dead.
0:02:12 > 0:02:16In this series, we'll dive back through history to uncover
0:02:16 > 0:02:20how one city helped forge victory in the Battle of the Atlantic.
0:02:29 > 0:02:31Late 1941.
0:02:31 > 0:02:33Derry had spent two years on the battle's front line
0:02:33 > 0:02:37and had seen the Germans hammer Allied shipping.
0:02:37 > 0:02:38In just three months that year,
0:02:38 > 0:02:43their U-boats sank more than 280 ships off the Northern Irish coast.
0:02:43 > 0:02:46But the Allies were determined to fight back.
0:02:46 > 0:02:50Warships crammed the Foyle and Derry filled with 30,000
0:02:50 > 0:02:53British, Canadian and American military personnel.
0:02:55 > 0:02:58The residents of Derry found themselves living
0:02:58 > 0:02:59in extraordinary times.
0:02:59 > 0:03:03The U-boats had brought the battle right to their doorstep.
0:03:03 > 0:03:06The people of this city came face-to-face with the tragedy
0:03:06 > 0:03:10and reality of World War II, but they dug deep and they got stuck in.
0:03:14 > 0:03:17Northern Ireland's war effort brought full employment to Derry,
0:03:17 > 0:03:19as the demand for exports increased.
0:03:19 > 0:03:22For the women, this meant new jobs making ammunition,
0:03:22 > 0:03:24linen and uniforms.
0:03:25 > 0:03:29They were in the factory and they all sort of went down for a smoke.
0:03:29 > 0:03:31It was all, "Where did you go last night?"
0:03:31 > 0:03:35And, "Who did you come home with?"
0:03:35 > 0:03:41Every morning, we had music while you worked, so life was good.
0:03:41 > 0:03:44There may have been hardships, but Derry's men and women
0:03:44 > 0:03:47met these with cheery resourcefulness.
0:03:47 > 0:03:52You couldn't get sugar, sweets, cigarettes were very scarce.
0:03:52 > 0:03:58Rationing was pretty strict but Donegal wasn't that far away.
0:03:58 > 0:04:02Oh, smuggling was big. Especially across the border.
0:04:02 > 0:04:04My mother and them had it down to a fine art.
0:04:04 > 0:04:09They got the train in Jones Street and they had bags under
0:04:09 > 0:04:14their skirts and they did quite a lot of smuggling, I'm telling you.
0:04:14 > 0:04:17And the presence of thousands of international troops
0:04:17 > 0:04:20in the city, brought its own advantages.
0:04:20 > 0:04:23American soldiers, they were terribly kind
0:04:23 > 0:04:26and they used to wander around and talk to the children
0:04:26 > 0:04:30and give the children sweets and maybe hand out cigarettes and things.
0:04:32 > 0:04:35An American used to appear every so often
0:04:35 > 0:04:38when the ship was in and one day, he brought us a banana.
0:04:39 > 0:04:43They were absolutely... You never knew what they were.
0:04:43 > 0:04:44But we auctioned it
0:04:44 > 0:04:47and got £3 for it in the middle of the war.
0:04:48 > 0:04:52Between all that and the dancing and the courting
0:04:52 > 0:04:55and come home with boys, and if they got too fresh
0:04:55 > 0:04:57you took to your heels and away you went
0:04:57 > 0:04:59because you were afraid of your mother.
0:04:59 > 0:05:02I must say, I thoroughly enjoyed the war.
0:05:04 > 0:05:07There may have been good times in Derry, but there was no
0:05:07 > 0:05:11escaping the grim reality of a city and a world at war.
0:05:13 > 0:05:20I remember going to dances at the Strand picture house
0:05:20 > 0:05:25on a Saturday night with the girls out of the office
0:05:25 > 0:05:30and Julie Glover, whose father was a chemist in William Street.
0:05:31 > 0:05:33He went away to the RAF.
0:05:36 > 0:05:41And he was shot down and...
0:05:45 > 0:05:49He would only have been about 19, I suppose.
0:05:51 > 0:05:53In military campaigns around the world,
0:05:53 > 0:05:56young men were losing their lives.
0:05:56 > 0:06:00But nowhere more so than in the Battle of the Atlantic,
0:06:00 > 0:06:05where 100,000 were killed. At its crux, were military supplies.
0:06:05 > 0:06:09Every week, huge convoys of cargo ships loaded with weaponry,
0:06:09 > 0:06:13oil and food, left the United States and Canada.
0:06:13 > 0:06:16Without them, the Allied war effort in Europe would grind to a halt.
0:06:16 > 0:06:19So Germany sent its U-boat fleet to sink
0:06:19 > 0:06:22the convoys before they reached their destinations.
0:06:30 > 0:06:33Underwater explorer, Ian Lawler, and his team of expert divers,
0:06:33 > 0:06:36are searching for lost wrecks of the battle.
0:06:36 > 0:06:38I can see the U-boat.
0:06:39 > 0:06:42They've already found the remains of a Corvette,
0:06:42 > 0:06:45a warship still loaded with ammunition.
0:06:45 > 0:06:49It is much more of a jigsaw puzzle than I expected.
0:06:49 > 0:06:51World naval experts, Dr Randy Papadopoulos
0:06:51 > 0:06:56and Dr Axel Niestle, are on hand to unlock the secrets of the wrecks.
0:06:56 > 0:07:00The acoustic homing torpedo would have targeted the loud engines
0:07:00 > 0:07:03of the Corvette and essentially would've blown her stern off.
0:07:03 > 0:07:06Dozens of Corvettes like this one moored up in Derry.
0:07:06 > 0:07:10Their job, to escort the convoys across the Atlantic and protect them
0:07:10 > 0:07:12from the U-boats which were deadly,
0:07:12 > 0:07:14as the team revealed
0:07:14 > 0:07:17when they discovered the wrecks of two German submarines.
0:07:17 > 0:07:20First, U-1003.
0:07:20 > 0:07:24Very capable fighting machines and very dangerous to the Allies.
0:07:26 > 0:07:28Then, U-155,
0:07:28 > 0:07:32a notorious sub that claimed the lives of nearly 1,000 men.
0:07:32 > 0:07:35During the war, all of these things are forgotten about.
0:07:35 > 0:07:37They're just incidental.
0:07:37 > 0:07:41But it's generally the divers that start to make the discoveries
0:07:41 > 0:07:44and try and shed light on what happened.
0:07:44 > 0:07:47When you find what you're looking for,
0:07:47 > 0:07:49that's what makes it all worthwhile.
0:07:51 > 0:07:54The wrecks also revealed Derry's role in the conflict.
0:07:55 > 0:07:58As Britain's most westerly port, it was essential,
0:07:58 > 0:08:01a key naval base for the armed escorts.
0:08:01 > 0:08:04It was the battle's frontline.
0:08:04 > 0:08:07And the city's hospitals were the first chance for the wounded
0:08:07 > 0:08:09to get life-saving treatment.
0:08:11 > 0:08:13Lexie Edgar was a nurse who volunteered
0:08:13 > 0:08:16with the St John's Ambulance.
0:08:16 > 0:08:18He met the battle scarred convoys at Lough Foyle
0:08:18 > 0:08:22and rushed their injured crews to hospital.
0:08:22 > 0:08:26We went down to where the heavy cruiser
0:08:26 > 0:08:29was protecting against submarines
0:08:29 > 0:08:36and we took the injured people off into smaller boats
0:08:36 > 0:08:39and brought them up to the Foyle.
0:08:39 > 0:08:44Any injuries we could help out with, we gave them... We dressed them up.
0:08:44 > 0:08:47Where there were more severely injured,
0:08:47 > 0:08:50we sent them off to city and county.
0:08:50 > 0:08:56I remember having to travel down and help a chap back.
0:08:56 > 0:09:01He was so badly injured and he was strapped from head to toe.
0:09:02 > 0:09:06There wasn't a lot left of him.
0:09:06 > 0:09:10His body, as I say, was covered in splinters.
0:09:12 > 0:09:15Lexie and his colleagues kept a logbook of the real human cost
0:09:15 > 0:09:17of the Battle of the Atlantic.
0:09:17 > 0:09:21On the face of it, this is a fairly simple record.
0:09:21 > 0:09:23Three columns, the date, the name of the ship
0:09:23 > 0:09:27and the number of passengers and crew that Lexie actually treated
0:09:27 > 0:09:29that came off it.
0:09:29 > 0:09:31And it does begin to tell you a fairly detailed story
0:09:31 > 0:09:33as to the growing human cost
0:09:33 > 0:09:38and human tragedy that was unfolding across the Atlantic.
0:09:38 > 0:09:42Broadly speaking, each page covers about five or six months
0:09:42 > 0:09:46and as it goes through the war, the numbers tell the story.
0:09:47 > 0:09:51Page one, he's treated 432 individuals.
0:09:51 > 0:09:53Here, 470.
0:09:53 > 0:09:59555, moving into 1943, 490.
0:09:59 > 0:10:01When you add it all together,
0:10:01 > 0:10:07you get a total of 3,401 recorded throughout the war.
0:10:07 > 0:10:10And on the back of this,
0:10:10 > 0:10:15is an interesting list of the sorts of cases that Lexie was treating.
0:10:15 > 0:10:20Fractured spine, fractured skull, concussion, machine gun wounds,
0:10:20 > 0:10:23bullet wounds, burns, of course,
0:10:23 > 0:10:27from the burning oil when the ship sank.
0:10:27 > 0:10:31And as you would expect, pneumonia.
0:10:31 > 0:10:33It's a simple book.
0:10:33 > 0:10:36When he wrote this, he never would have expected that this would
0:10:36 > 0:10:39become an important historic document.
0:10:39 > 0:10:40But it is.
0:10:43 > 0:10:47The injured who made it to Derry for treatment were the lucky ones.
0:10:47 > 0:10:51100,000 never came home from the battle.
0:10:51 > 0:10:554,000 shipwrecks on the Atlantic seabed remind us of their sacrifice.
0:11:00 > 0:11:02Adding to the deadly threat of the U-boats,
0:11:02 > 0:11:04was the Atlantic weather.
0:11:04 > 0:11:07High winds and violent seas could be deadly.
0:11:07 > 0:11:10For underwater explorer, Ian Lawler, and his team of divers,
0:11:10 > 0:11:12it's no different.
0:11:12 > 0:11:16It's September and they're on the Rosguill Peninsula in north Donegal
0:11:16 > 0:11:20hoping to dive a wreck 20 miles offshore.
0:11:20 > 0:11:23But today's rough seas could make it too dangerous.
0:11:25 > 0:11:27It's not looking good.
0:11:27 > 0:11:29You're trying to stagger around in a pair of fins on the back
0:11:29 > 0:11:32of a rolling boat with the equivalent of your own body weight
0:11:32 > 0:11:34on your back.
0:11:34 > 0:11:39The boat is rising and falling a metre to two metres.
0:11:39 > 0:11:43That is not an option. It could remove people's heads.
0:11:43 > 0:11:46With the best skipper in the world, the best will in the world,
0:11:46 > 0:11:48that is very dangerous.
0:11:48 > 0:11:52Anybody gets it wrong, through attention or a mistake,
0:11:52 > 0:11:55you know, you could be seriously injured.
0:12:03 > 0:12:06Skipper, Michael, goes to check conditions one last time
0:12:06 > 0:12:08but the weather has got worse.
0:12:08 > 0:12:12Even the sheltered waters of the bay are looking choppy.
0:12:14 > 0:12:17The day is lost. Gone, nothing.
0:12:25 > 0:12:29Deepwater veteran and dive supervisor, Rich Stevenson,
0:12:29 > 0:12:30is in charge of safety
0:12:30 > 0:12:34and used to assessing the dangers of an expedition.
0:12:34 > 0:12:36It's a force of nature, isn't it?
0:12:36 > 0:12:40When you can't stand up against something that you can't see.
0:12:44 > 0:12:46You've got to pit your wits against the weather
0:12:46 > 0:12:50and everything else that you're up against, as well.
0:12:50 > 0:12:53You can topple over at a moment's notice.
0:12:53 > 0:12:56It's unthinkable to try and dive in these conditions.
0:12:56 > 0:12:59It's a reminder of the bravery of the Atlantic crews,
0:12:59 > 0:13:01who fought on, whatever the weather.
0:13:01 > 0:13:04Very aware of the historical significance
0:13:04 > 0:13:08of this area of water and what lies beneath the waves.
0:13:08 > 0:13:11You can't even imagine what it must be like to be caught out
0:13:11 > 0:13:13in the open ocean in those conditions.
0:13:14 > 0:13:17But weather like this and worse,
0:13:17 > 0:13:21was a fact of life for men working the Atlantic convoy routes.
0:13:21 > 0:13:23The busiest of them all passed through some of the Atlantic's
0:13:23 > 0:13:27wildest water, from Newfoundland in Canada to Derry.
0:13:27 > 0:13:31Over the war, it introduced thousands of Canadian sailors
0:13:31 > 0:13:32to the city.
0:13:32 > 0:13:35The Royal Canadian Navy, which had been very small,
0:13:35 > 0:13:38just a coastal patrol service at the beginning of the war,
0:13:38 > 0:13:41burgeoned to the point, where by 1943,
0:13:41 > 0:13:44it's the third largest Navy in the world.
0:13:44 > 0:13:48If you look at the 100 plus escort ships that are based on the Foyle,
0:13:48 > 0:13:52the vast majority of them are Royal Canadian Navy.
0:13:52 > 0:13:55To Canadian sailors, the route was legendary,
0:13:55 > 0:13:57known as the Newfie Derry run.
0:13:58 > 0:13:5918-year-old Gilbert Davis,
0:13:59 > 0:14:03was a stoker on the Canadian escort ship, Merrittonia.
0:14:03 > 0:14:07Wherever he went, he brought his camera.
0:14:07 > 0:14:10The camera was a small camera. It was a dollar 50 camera.
0:14:10 > 0:14:12It was one of the first things he ever bought.
0:14:12 > 0:14:15But Gilbert put it to good use, documenting his life
0:14:15 > 0:14:19during the Battle of the Atlantic and not just at sea.
0:14:19 > 0:14:21Every month he spent time in Derry
0:14:21 > 0:14:24and his pictures give a sailor's view of the city.
0:14:25 > 0:14:28Approaching the packed docks from the Foyle,
0:14:28 > 0:14:32the Allied escort ships moored four deep.
0:14:34 > 0:14:35And wartime Bishopsgate.
0:14:38 > 0:14:40One place that struck Gilbert,
0:14:40 > 0:14:44as a unique spot in Londonderry, was Bishopsgate,
0:14:44 > 0:14:47because he understood it was built some time in the 16th century.
0:14:47 > 0:14:51That kind of history he hadn't seen over in North America.
0:14:51 > 0:14:53Just like all Atlantic crews,
0:14:53 > 0:14:55Gilbert arrived in Derry with relief.
0:14:55 > 0:14:57It marked the end of another perilous crossing,
0:14:57 > 0:14:59not only giving U-boats the slip,
0:14:59 > 0:15:03but also surviving the high seas and violent winds of the Atlantic.
0:15:05 > 0:15:09The North Atlantic has some of the most unforgiving sea on the planet, really.
0:15:09 > 0:15:15That makes it very difficult to have any sort of cargo, or naval operation take place.
0:15:15 > 0:15:19Gilbert's photos show the rough seas the Atlantic crews faced.
0:15:19 > 0:15:23With the ships rolling in giant swells, Corvettes like Gilbert's
0:15:23 > 0:15:28still had to attempt essential tasks like refuelling on the move.
0:15:28 > 0:15:33Mountains of water, 30, 40, 60 feet high, and he would be hunkered down
0:15:33 > 0:15:36as close as he could to the security of the ship itself.
0:15:36 > 0:15:39The Atlantic can be savage.
0:15:39 > 0:15:44But wild weather was always preferable to an encounter with a submarine.
0:15:44 > 0:15:48There was always the threat of attack from a U-boat.
0:15:48 > 0:15:52That itself must have frayed the nerves of many a crewman.
0:15:52 > 0:15:56And here we have an example of the aftermath.
0:15:56 > 0:16:00Clearly, a tanker has been hit. The ship itself is obscured
0:16:00 > 0:16:04in billowing clouds of black, acrid smoke,
0:16:04 > 0:16:07and the sea all around it, ablaze.
0:16:07 > 0:16:10The tanker had been carrying thousands of tonnes of fuel.
0:16:10 > 0:16:13He was on the bow of his ship taking photographs.
0:16:13 > 0:16:18He said he had to hold his hand up and guard his face from the heat, it was so intense.
0:16:18 > 0:16:21On the horizon is the tanker burning,
0:16:21 > 0:16:25and here alongside the hull of his ship, one man,
0:16:25 > 0:16:27the only survivor from that attack.
0:16:29 > 0:16:33Dwarfed by the tower of smoke and the vast Atlantic,
0:16:33 > 0:16:35this man had suffered horrific injuries.
0:16:35 > 0:16:38They pulled him aboard the Maritonia,
0:16:38 > 0:16:43and as he was pulled from the water by a seaman,
0:16:43 > 0:16:48all of the skin from his arm had pulled off because he was so badly burned.
0:16:49 > 0:16:53Over 70 years later, the pictures taken by Gilbert Davis
0:16:53 > 0:16:56give a remarkable insight into the reality of a sailor's life
0:16:56 > 0:16:58fighting the Battle of the Atlantic.
0:17:01 > 0:17:03It's one man's record of a campaign
0:17:03 > 0:17:06that cost the lives of thousands more.
0:17:20 > 0:17:23The dive team are getting ready for their fourth expedition.
0:17:23 > 0:17:27They're hoping to uncover the wreck of the U-boat Ian believes
0:17:27 > 0:17:30was sunk in the heat of battle just 10 miles from Coleraine.
0:17:34 > 0:17:37But on the Rosguill Peninsula, another storm is brewing.
0:17:37 > 0:17:40The team are hoping to beat the incoming weather
0:17:40 > 0:17:43by heading for Port Stewart and diving from there.
0:17:43 > 0:17:45I'm not sure just yet.
0:17:45 > 0:17:50This large area of Donegal could give us a bit of shelter.
0:17:50 > 0:17:54That would be a lot better. It is a narrow weather window but it's an option.
0:17:54 > 0:17:57They plan to use a high-speed rib to race out to the wreck
0:17:57 > 0:18:00and back again before the winds hit.
0:18:00 > 0:18:03I think it gives us some advantages in certainly speed getting out of there.
0:18:03 > 0:18:08- But maybe less home comforts. - It's quite a stable boat, but you have to hang on.
0:18:11 > 0:18:15The team has allowed just 30 minutes to get to the dive site.
0:18:15 > 0:18:18And already the winds are picking up.
0:18:18 > 0:18:22The high-speed twin engine rib has to battle through the swirl,
0:18:22 > 0:18:24while do team do their best to hang on.
0:18:29 > 0:18:32With the weather closing in, there isn't a minute to lose.
0:18:32 > 0:18:36Once on site, it's straight into the water.
0:18:36 > 0:18:39The strong surface swell sweeps the divers from the boat.
0:18:50 > 0:18:53Once underwater, they locate the grapple line.
0:18:53 > 0:18:56It should lead them 200 feet straight down
0:18:56 > 0:18:59directly to the wreck on the seabed.
0:18:59 > 0:19:03But the strong current has ripped the grapple off the wreckage,
0:19:03 > 0:19:05leaving them searching blindly through the silt.
0:19:12 > 0:19:18But then, the beam from a torchlight falls on the rusting hull of a U-boat.
0:19:18 > 0:19:24It's over 250 feet long and shows all the hallmarks of a type seven,
0:19:24 > 0:19:27the workhorse of the German fleet.
0:19:29 > 0:19:32But what intrigues the team is the damage to the hull.
0:19:35 > 0:19:38Along its entire length, it's been shattered,
0:19:38 > 0:19:41the thick steel ripped open.
0:19:41 > 0:19:47This wreck shows all the tell-tale signs of a devastating depth charge attack.
0:20:24 > 0:20:28Having had just 20 minutes to gather the evidence they need,
0:20:28 > 0:20:31the team now make a controlled two hour assent back to their boat.
0:20:33 > 0:20:35As they pile aboard,
0:20:35 > 0:20:38Ian can't contain his excitement at what he's seen.
0:20:55 > 0:20:58The extensive damage to the U-boat
0:20:58 > 0:21:01is the first sign that the enormous efforts in Derry
0:21:01 > 0:21:03to win the Battle of the Atlantic were paying off.
0:21:03 > 0:21:08In 1941, the Allies sank just 40 U-boats.
0:21:08 > 0:21:12In 1943, they sank 270.
0:21:12 > 0:21:14But with so many German submarines sunk,
0:21:14 > 0:21:17it could be difficult for naval experts
0:21:17 > 0:21:19Randy Papadopoulos and Axel Niestle
0:21:19 > 0:21:22to identify the wreck Ian and the team have found.
0:21:23 > 0:21:27This is a pretty jagged hole here.
0:21:27 > 0:21:32And all the plate is just pushed inward.
0:21:32 > 0:21:35The pushed in plating that we're seeing here suggests that
0:21:35 > 0:21:38something came in from the outside - an explosion, probably.
0:21:38 > 0:21:44That's heavy structural damage. This is simply crushed.
0:21:44 > 0:21:48- Here we are on the broken end of a snorkel.- Oh, yeah.
0:21:48 > 0:21:55And then the conning tower area is devastated. Absolutely demolished.
0:21:55 > 0:21:57This is quite cataclysmic damage.
0:21:57 > 0:22:01So that needs a depth charge exploding almost on contact.
0:22:01 > 0:22:04- Hundreds of pounds of explosives. - Yes.
0:22:06 > 0:22:09Depth charges were the most common antisubmarine weapon.
0:22:09 > 0:22:12Once Allied ships had detected a U-boat,
0:22:12 > 0:22:16they would target depth charges over the entire area.
0:22:16 > 0:22:18The shockwaves created by the explosions
0:22:18 > 0:22:22could tear open the hull of a U-boat lurking beneath the surface.
0:22:28 > 0:22:33But you see the thickness of the steel has just been torn, like paper.
0:22:33 > 0:22:36- The Royal Navy named it "tin-opener attacks".- Yes.
0:22:36 > 0:22:41That's exactly what has happened obviously to this wreck.
0:22:42 > 0:22:45Axel and Randy use the location of the wreck
0:22:45 > 0:22:47and the knowledge it was pummelled by depth charges
0:22:47 > 0:22:51to search naval records for information to identify it.
0:22:51 > 0:22:53At last, they find a match.
0:22:53 > 0:22:59From what we know, I think we can surely say that this is 1014.
0:22:59 > 0:23:04All what we have found here is consistent with that identification.
0:23:06 > 0:23:11Ian and the team's dive has revealed the wreck as U-1014,
0:23:11 > 0:23:14a late war Type VII submarine.
0:23:14 > 0:23:16It was just 18 days into its first patrol
0:23:16 > 0:23:19when a group of British escort ships detected it
0:23:19 > 0:23:22eight miles off the coast of Northern Ireland.
0:23:23 > 0:23:27They fell into formation and together began to hunt it down.
0:23:27 > 0:23:31It's a bit of a ballet of ships, if you will.
0:23:31 > 0:23:33All the time moving because the U-boat in addition
0:23:33 > 0:23:37is trying to escape and all the ships are trying to keep in contact with it
0:23:37 > 0:23:39and put the ordnance where it's needed.
0:23:39 > 0:23:42So when they come across a contact, the first thing you do
0:23:42 > 0:23:45is start trying to pulverise it with as many depth charges
0:23:45 > 0:23:47- or Hedgehog or Squid - whatever weapons they've got available
0:23:47 > 0:23:49and make sure you've gotten him,
0:23:49 > 0:23:53rather than take a chance and let it get away.
0:23:53 > 0:23:56It was finally destroyed while being under the water.
0:23:58 > 0:24:02Beneath the surface, the Allied depth charges found their target.
0:24:02 > 0:24:06All 48 men inside u1014 were killed.
0:24:06 > 0:24:10From 1943, German losses like this were increasingly common,
0:24:10 > 0:24:14as the scales began to tip in the Allies' favour.
0:24:16 > 0:24:20But it's just one more reminder to the U-boat crews
0:24:20 > 0:24:22that are still surviving
0:24:22 > 0:24:25that actually their time is going to be limited
0:24:25 > 0:24:28because their losses are just simply unsustainable.
0:24:29 > 0:24:32As the German Kriegsmarine lost more and more of its crews,
0:24:32 > 0:24:37it became harder and harder to replace them with experienced men.
0:24:37 > 0:24:40Most of the crew on U-1014 were younger than 22.
0:24:40 > 0:24:47These were green soldiers, sent out into a battle against an enemy
0:24:47 > 0:24:50which was gaining experience everyday.
0:24:50 > 0:24:54This is the Allied navies at the top of the antisubmarine warfare game,
0:24:54 > 0:24:58with tactics customised to deal with the inshore threat.
0:24:58 > 0:25:01The crew of the British escort ships
0:25:01 > 0:25:04had no idea which U-boat they had sunk.
0:25:04 > 0:25:07They searched the wreckage that floated to the surface
0:25:07 > 0:25:10for anything that might identify their victim.
0:25:10 > 0:25:12One everyday item give them a clue.
0:25:12 > 0:25:16From the debris picked up after the attack,
0:25:16 > 0:25:20there were a pair of underpants picked up with a name on it.
0:25:20 > 0:25:24And this name was Moose.
0:25:24 > 0:25:28By searching German naval records, Axel has been able to reveal
0:25:28 > 0:25:31that Seaman Moose was a 19-year-old engineer mechanic
0:25:31 > 0:25:36and that his last recorded patrol was on-board U-1014.
0:25:36 > 0:25:39So this is just another support
0:25:39 > 0:25:45that the boat being lost in this area is 1014.
0:25:50 > 0:25:55Identifying the wreck is another success for Ian and the team -
0:25:55 > 0:25:58another name to add to his chart.
0:25:58 > 0:26:03But their discovery also marks the war grave of 48 young submariners.
0:26:04 > 0:26:06It reveals how the Allies' determination
0:26:06 > 0:26:08to keep the convoy routes open,
0:26:08 > 0:26:11alongside their growing expertise in hunting submarines,
0:26:11 > 0:26:15was now beginning to overpower the German U-boat fleet.
0:26:20 > 0:26:22'The Allies may at last have been
0:26:22 > 0:26:25'turning the Battle of the Atlantic in their favour,
0:26:25 > 0:26:29'but one fatal chink remained - fully effective air cover.
0:26:30 > 0:26:34'From 1940, Allied airplanes patrolled parts of the Atlantic,
0:26:34 > 0:26:36'flying from coastal bases
0:26:36 > 0:26:39in Canada, Iceland and Northern Ireland.'
0:26:39 > 0:26:43Whenever a U-boat sees an airplane,
0:26:43 > 0:26:46the first temptation for that U-boat commander is to dive.
0:26:46 > 0:26:48Once you've forced him below the water,
0:26:48 > 0:26:52he's reduced to about four to seven knots.
0:26:52 > 0:26:55So it's a brisk walk or a slow trot,
0:26:55 > 0:26:59but it's certainly slower than even the slow convoys
0:26:59 > 0:27:02which are travelling at about nine or 10 knots.
0:27:02 > 0:27:05It means that he cannot pursue the convoy anywhere near as effectively.
0:27:05 > 0:27:08His visibility is hindered at the very least.
0:27:08 > 0:27:11But, at best, it means the U-boat will have to break off its contact
0:27:11 > 0:27:15with the convoy and won't be able to pursue it and hunt it any longer.
0:27:15 > 0:27:17But the aeroplanes had limited range
0:27:17 > 0:27:22and a vast area of the Atlantic remained unprotected from the air.
0:27:22 > 0:27:25This was known as the Mid-Atlantic Gap,
0:27:25 > 0:27:28and, for the Germans, the lack of air cover here
0:27:28 > 0:27:30made it a prime hunting ground.
0:27:30 > 0:27:32It was a gap the Allies needed to close.
0:27:34 > 0:27:36So the Royal Navy set about
0:27:36 > 0:27:39creating the largest air squadron in the UK,
0:27:39 > 0:27:41and they based it here in Derry.
0:27:41 > 0:27:44It was a decision that would change the course of the battle.
0:27:45 > 0:27:49The plan was for Swordfish biplanes to fly from Maydown
0:27:49 > 0:27:52at the edge of the city, land on makeshift aircraft carriers
0:27:52 > 0:27:56off the coast, and, for the first time, accompany the convoys
0:27:56 > 0:27:59to fly anti-U-boat patrols in the mid-Atlantic.
0:28:01 > 0:28:05Eventually, 100 of these planes operated from Derry's new airbase.
0:28:07 > 0:28:10We're stepping onto the runways of HMS Shrike.
0:28:10 > 0:28:12And if you'd been here 70 years ago,
0:28:12 > 0:28:15amid the noise and the bustle and so forth,
0:28:15 > 0:28:19you might have been able to see three or four Swordfish biplane bombers
0:28:19 > 0:28:23taking off here on the westerly runway, heading out towards Donegal
0:28:23 > 0:28:25and then turning out into the Atlantic,
0:28:25 > 0:28:28where they would join a small merchant aircraft carrier.
0:28:31 > 0:28:33The merchant aircraft carriers, or MAC-ships,
0:28:33 > 0:28:36were simply cargo vessels with their superstructure removed
0:28:36 > 0:28:39and a few hundred feet of runway welded on instead.
0:28:39 > 0:28:43They may have been crude, but with their Swordfish biplanes,
0:28:43 > 0:28:46these MAC-ships proved highly effective.
0:28:48 > 0:28:51These are very important because they'll provide each convoy
0:28:51 > 0:28:53with its own aircraft carrier protection.
0:28:55 > 0:28:58Right from the very beginning
0:28:58 > 0:29:02of this airfield's existence as a naval base in May of 1943,
0:29:02 > 0:29:06we see the Battle of the Atlantic swing in the Allies' favour.
0:29:06 > 0:29:10From then on, every convoy is covered by Swordfish
0:29:10 > 0:29:15and basically the U-boats daren't operate on the surface any more.
0:29:20 > 0:29:23Bob Lee was a telegraphist air gunner with the Swordfish crews
0:29:23 > 0:29:27based in Derry. He flew every day in any weather,
0:29:27 > 0:29:30standing in the open cockpit at the rear of the Swordfish.
0:29:34 > 0:29:38Cold. I don't know why it was always cold.
0:29:38 > 0:29:43It seemed to be the worst where we were, you know.
0:29:43 > 0:29:48Either in Canada or Northern Ireland. It was always damn cold.
0:29:48 > 0:29:52Bob faced danger too, every day.
0:29:52 > 0:29:56Just landing a Swordfish on an improvised aircraft carrier
0:29:56 > 0:29:58was a hit-and-miss affair.
0:29:58 > 0:30:01More than once, he found himself in the drink.
0:30:01 > 0:30:06He started to dip down and I thought, "There's something wrong here.
0:30:06 > 0:30:12"What's up," you know? And the pilot was pump-pump-pumping.
0:30:12 > 0:30:17Something wrong. "Mayday, Mayday, Mayday. This is Swordfish Ellis 246."
0:30:17 > 0:30:19Bosch.
0:30:19 > 0:30:23And then I heard, "All right, 246, come into land, you're clear.
0:30:23 > 0:30:26I thought he'd got the wrong bloody aircraft!
0:30:26 > 0:30:29Bob's Swordfish had been given the wrong instructions.
0:30:29 > 0:30:33His plane overshot the landing deck of the aircraft carrier
0:30:33 > 0:30:35and smashed into the sea.
0:30:35 > 0:30:40But, as was the rule, the convoy didn't stop. Bob was left behind.
0:30:43 > 0:30:45If the whole group of ships stops,
0:30:45 > 0:30:48that whole 40 ship target is a target.
0:30:48 > 0:30:52The commodore has no choice but to keep going and let them go.
0:30:52 > 0:30:53And a lot of them perished
0:30:53 > 0:30:56because they can't have an immediate rescue come to them.
0:30:56 > 0:30:59It's a very risky business, not easy to manage
0:30:59 > 0:31:03and it cost a lot of people their lives when things go wrong.
0:31:03 > 0:31:06Bob was left to drift in the cold Atlantic,
0:31:06 > 0:31:11clinging to the wreckage of his biplane as the convoy steamed on.
0:31:11 > 0:31:16After about half an hour, along came another Swordfish,
0:31:16 > 0:31:19dropped a couple of dinghies which still didn't work
0:31:19 > 0:31:21and I thought, "That's it."
0:31:23 > 0:31:26They talk about your whole life flashing before you.
0:31:26 > 0:31:29But all you think about was
0:31:29 > 0:31:33what the people back home will think when they know I'm dead.
0:31:33 > 0:31:35That was it.
0:31:35 > 0:31:39Bob was eventually rescued by an escort ship,
0:31:39 > 0:31:43but he continued to fly, clocking up over 200 hours in the air.
0:31:43 > 0:31:47It was a crucial job, and Bob and his fellow crews at Maydown
0:31:47 > 0:31:50succeeded in forcing the U-boats to remain submerged.
0:31:51 > 0:31:57The availability of those aircraft from mid-1943 onwards in every convoy
0:31:57 > 0:32:01meant that there was no part of the ocean that was safe,
0:32:01 > 0:32:04as far as the U-boats were concerned,
0:32:04 > 0:32:08from the eyes of Allied airmen in the sky above.
0:32:09 > 0:32:14The Swordfish were the vital missing piece of the anti-U-boat strategy.
0:32:14 > 0:32:18And Maydown became critical to keeping the Mid-Atlantic Gap closed.
0:32:18 > 0:32:22The base quickly grew in size, with two British and Dutch
0:32:22 > 0:32:25air squadrons operating from here over the war.
0:32:27 > 0:32:28One RAF Wren who experienced
0:32:28 > 0:32:31how cosmopolitan life at Maydown became was Mary Piper.
0:32:34 > 0:32:37It was the women's Royal Naval service,
0:32:37 > 0:32:40so that's why she was here, because of the convoys.
0:32:40 > 0:32:44She did a lot of the organising of social events and entertainment.
0:32:44 > 0:32:46She looked after menus
0:32:46 > 0:32:49for different functions and so forth.
0:32:49 > 0:32:50I think there was a party
0:32:50 > 0:32:52that she was organising
0:32:52 > 0:32:56and she invited some of the men from - the officers -
0:32:56 > 0:32:58from Dad's 860 Squadron.
0:32:59 > 0:33:03860 Squadron was made up entirely of Dutch aircrew
0:33:03 > 0:33:06who had fled Holland after the Nazi invasion.
0:33:06 > 0:33:11One of them was Hugo Jellema, a young flight navigator.
0:33:11 > 0:33:16She always said that she first saw Dad at the top of the stairs
0:33:16 > 0:33:20and she thought, "Hmm, he looks OK," or some such thing!
0:33:22 > 0:33:26Aw! All starry-eyed.
0:33:26 > 0:33:30Both Hugo and Mary kept scrapbooks of their time in the war.
0:33:30 > 0:33:32These record their blossoming romance,
0:33:32 > 0:33:35as well as daily life at Maydown.
0:33:35 > 0:33:38Their daughters only recently discovered them in an attic.
0:33:43 > 0:33:48So she's gathered all sorts of things.
0:33:48 > 0:33:51I mean, there's a picture of a band.
0:33:51 > 0:33:55"Boy, did they play Take The Train well!"
0:33:55 > 0:33:58There's a dinner dance.
0:33:58 > 0:34:01"A never to be forgotten night at the club with Hugo.
0:34:01 > 0:34:05"Back to Belmont in the pouring rain in evening dress!"
0:34:05 > 0:34:08I think there was quite a lot of socialising going on.
0:34:08 > 0:34:13- Well-deserved.- To take their mind off the serious stuff.
0:34:19 > 0:34:21Mum was working in the Wrens
0:34:21 > 0:34:26- and Dad was back and forth, flying all the time.- Yes.
0:34:26 > 0:34:28It looks from this that they were together a lot,
0:34:28 > 0:34:31but I think actually they weren't together that often
0:34:31 > 0:34:34because Dad was out supporting the convoys,
0:34:34 > 0:34:38flying his various Swordfish back and forth across the Atlantic.
0:34:38 > 0:34:43And each of those trips took three weeks.
0:34:43 > 0:34:45Look at this one.
0:34:46 > 0:34:51"Just arrived. Received your letter. No leave permitted.
0:34:51 > 0:34:54"Any chance of seeing you?" Aw, how sweet.
0:34:55 > 0:34:57Dad was really very fortunate.
0:34:57 > 0:35:01I mean, he did all these things and he had hairy experiences,
0:35:01 > 0:35:03but, I mean, he'd tell of other people
0:35:03 > 0:35:06- who were not as lucky as he was. - He came home. Some of them didn't.
0:35:09 > 0:35:10A rediscovered wartime film
0:35:10 > 0:35:13of their dad's plane about to land on a MAC-ship
0:35:13 > 0:35:16gives the sisters an insight into his bravery.
0:35:17 > 0:35:21Oh! Oh, my goodness. Looks like they missed that time.
0:35:21 > 0:35:26So Dad's telling the pilots how to come down. You know,
0:35:26 > 0:35:27"Left a bit, right a bit."
0:35:27 > 0:35:30Yeah. Because the pilot couldn't see.
0:35:30 > 0:35:33This is him trying to land. Oh, my goodness.
0:35:33 > 0:35:36- "Down a bit, up a bit." What a dangerous job that is.- I know.
0:35:36 > 0:35:40Because he nearly gets his head cut off with the wing.
0:35:40 > 0:35:43Oh! Safely down.
0:35:43 > 0:35:46Oh! There they are!
0:35:52 > 0:35:56- I mean, Dad must have only been about 19 then.- Yes.
0:36:00 > 0:36:05- Ditching a crashed plane.- Oh.
0:36:05 > 0:36:08How relieved they must be to actually get out of the plane.
0:36:08 > 0:36:10Get out of the crashed one.
0:36:10 > 0:36:13Mum must have been quite nervous and anxious about him
0:36:13 > 0:36:17all that time he was away. It was a very hazardous thing to do.
0:36:22 > 0:36:26- Dad and his mates larking around. - That's it!
0:36:28 > 0:36:31They were pretending that they had to be mad to do this job,
0:36:31 > 0:36:34so they were kind of all twitching.
0:36:34 > 0:36:36- Oh, that's the Batman.- Oh, yes!
0:36:36 > 0:36:39- What are they doing? - THE SISTERS LAUGH
0:36:39 > 0:36:42It must have been a sunny day. They're out on the deck.
0:36:42 > 0:36:45That's what I was thinking, mid-Atlantic,
0:36:45 > 0:36:48I was surprised that they would be out sunbathing.
0:36:48 > 0:36:52- There's Dad!- Oh, my goodness!
0:36:52 > 0:36:58- He's chewing gum.- Oh, wow.
0:37:04 > 0:37:0770 years later, this forgotten archive shows
0:37:07 > 0:37:09a young man still in his teens
0:37:09 > 0:37:13trying to lead an ordinary life in extraordinary circumstances.
0:37:13 > 0:37:17It's absolutely gorgeous to see. And I feel like
0:37:17 > 0:37:21I want to take him out of the screen and give him a hug.
0:37:26 > 0:37:28Hugo Jellema crossed the Atlantic
0:37:28 > 0:37:30many times and had many narrow escapes.
0:37:30 > 0:37:34But he survived the war, not to return to his native Holland,
0:37:34 > 0:37:38but to marry his Northern Irish love, Mary Piper.
0:37:39 > 0:37:43They lived the rest of their lives together in Belfast.
0:37:45 > 0:37:50- It's very emotional to watch that, really.- Terrific.
0:37:50 > 0:37:52- We're very lucky to have it. - Very special.
0:38:04 > 0:38:07The dive team is back on the Rosguill Peninsula, continuing
0:38:07 > 0:38:12their mission to map the lost wrecks of the Battle of the Atlantic.
0:38:12 > 0:38:14Today they're hunting another U-boat
0:38:14 > 0:38:17and this time Ian already has a hunch which one it might be.
0:38:17 > 0:38:21As they head out, he shares his thoughts with the team.
0:38:21 > 0:38:24- What number have you assigned to this one?- 1104.- 1104.
0:38:24 > 0:38:29- What type of sub is the 1104? - Type VIIC.- 7C?
0:38:32 > 0:38:34The dive will confirm whether Ian's right.
0:38:34 > 0:38:37But with a heavy swell developing, the divers waste no time
0:38:37 > 0:38:40kitting up and dropping over the side.
0:39:10 > 0:39:14190 feet from the surface, they have enough light to peer
0:39:14 > 0:39:17straight down the conning tower, into the control room.
0:39:17 > 0:39:21This is where a German U-boat commander would once have stood
0:39:21 > 0:39:23and planned his attack.
0:39:25 > 0:39:30The conning tower shows no damage. And the periscopes are still intact.
0:39:35 > 0:39:39The U-boat appears to be in good condition.
0:39:39 > 0:39:43But just a few yards further on, the hull comes to a sudden stop.
0:39:44 > 0:39:48It's as if the U-boat has been snapped perfectly in two.
0:39:50 > 0:39:53Why, however, remains a mystery.
0:39:59 > 0:40:04The team search for clues to explain what happened, and find no answers.
0:40:04 > 0:40:08But, as Ian heads for the surface, one thing is clear.
0:40:08 > 0:40:13He thought this was U-1104, a type VII U-boat.
0:40:13 > 0:40:15He was completely wrong.
0:40:15 > 0:40:20Hang on a second, this is too big. This is just way too big!
0:40:20 > 0:40:25It's not a Type VIIC Atlantic. It's definitely a Type IX. Start again.
0:40:25 > 0:40:29It's a double mystery for the team. Which U-boat is it?
0:40:29 > 0:40:33And how was it broken so cleanly in half?
0:40:33 > 0:40:36I can't imagine she ruptured or somebody fired a shell at it,
0:40:36 > 0:40:38or whatever. It's a very clean break.
0:40:38 > 0:40:43Whoever did the blasting job on that had a work of art.
0:40:43 > 0:40:46It sort of adds to the whole sort of confusion of what it is.
0:40:46 > 0:40:49So... Back to the drawing board.
0:40:55 > 0:40:58So, will naval experts Dr Randy Papadopoulos
0:40:58 > 0:41:03and Dr Axel Niestle be able to shed light on the mystery U-boat?
0:41:03 > 0:41:07I looked at it and went, "This is not what I was expecting."
0:41:09 > 0:41:12Well, from everything we see right now,
0:41:12 > 0:41:16it's definitely not the Type VIIC.
0:41:16 > 0:41:18Because the deck is simply too wide.
0:41:18 > 0:41:21- So this is the aft end of the pressure hull, is it?- Yes.
0:41:21 > 0:41:23There should be two openings in it.
0:41:23 > 0:41:26For the two aft torpedo tubes.
0:41:26 > 0:41:29- One.- One, two.
0:41:29 > 0:41:32This, at least, solves the mystery for the type.
0:41:32 > 0:41:36- This U-boat is a Type IX.- Yeah.
0:41:36 > 0:41:40So this wreck is broken completely and half.
0:41:40 > 0:41:43We'll just see the damage here.
0:41:43 > 0:41:45Ian shows the two experts
0:41:45 > 0:41:48the extraordinary break in the U-boat's hull.
0:41:48 > 0:41:51It's unlike anything they've seen before.
0:41:54 > 0:41:56- Just look at how clean this is. - That's amazing.
0:41:56 > 0:41:58Absolutely extraordinary.
0:41:58 > 0:42:01It's all along one of these pressure hull frames.
0:42:01 > 0:42:04It's like somebody sliced it off with a cleaver.
0:42:04 > 0:42:06But with only half a wreck,
0:42:06 > 0:42:10it's difficult for Axel and Randy to make a precise ID.
0:42:10 > 0:42:14Only the U-boat's type and its location are certain, so they scour
0:42:14 > 0:42:18German and British files for records of any Type IX sunk in the area.
0:42:18 > 0:42:20And at last they find a likely match.
0:42:22 > 0:42:27Now, you've been studying the wreck of the infamously named U-broken,
0:42:27 > 0:42:29effectively half a U-boat.
0:42:29 > 0:42:33Any clues as to what kind of a boat it was and what happened to it?
0:42:33 > 0:42:40At the moment, we just can speculate that it is probably U-541,
0:42:40 > 0:42:43which, according to the records, had gone down close to this location.
0:42:43 > 0:42:48What could have caused that to happen? Presumably something like a torpedo?
0:42:48 > 0:42:51If a torpedo explodes underneath, of course,
0:42:51 > 0:42:54it will lift up the whole boat bodily
0:42:54 > 0:42:57and will be able certainly to break it in part,
0:42:57 > 0:43:01but according to the records this boat was not torpedoed.
0:43:02 > 0:43:05So what did cause this unusual damage?
0:43:05 > 0:43:09In attempting to solve one mystery, the team have stumbled on another.
0:43:09 > 0:43:14But from only half a U-boat, they have made a likely identification.
0:43:14 > 0:43:16U-541.
0:43:22 > 0:43:26This submarine opens the final chapter in Derry's wartime story.
0:43:26 > 0:43:30After Britain defeated the German armies in Europe in 1945,
0:43:30 > 0:43:32the U-boat fleet was ordered to surrender.
0:43:32 > 0:43:37And over 100 submarines assembled on the River Foyle.
0:43:37 > 0:43:41Victory was made official when the German crews handed over their boats
0:43:41 > 0:43:45and were taken ashore as prisoners of war.
0:43:45 > 0:43:46That happened on 14 May 1945
0:43:46 > 0:43:50when a flotilla of about eight U-boats came in.
0:43:50 > 0:43:56They made their formal surrender on the jetty at the Lisahally
0:43:56 > 0:43:59and formerly brought the Battle of the Atlantic to an end.
0:44:00 > 0:44:04For the entire war, Derry had battled the U-boat.
0:44:04 > 0:44:06Now they were moored in the city.
0:44:06 > 0:44:11Locals did everything they could not just to see one but to get on-board.
0:44:20 > 0:44:25My uncle, he managed to get me on one of the U-boats,
0:44:25 > 0:44:28you could hardly move on them they were that bloody tight.
0:44:28 > 0:44:31They were very cramped, you'd wonder how people could have lived on them,
0:44:31 > 0:44:32especially under the water.
0:44:34 > 0:44:38But the real prize was to get your hands on a souvenir.
0:44:38 > 0:44:41And soon Derry was awash with U-boat memorabilia.
0:44:44 > 0:44:47Everybody in Derry had something off the U-boats.
0:44:47 > 0:44:50Everybody could show you something that came off the U-boats.
0:44:50 > 0:44:52I had a friend down the street
0:44:52 > 0:44:58who had an identity book for one of the officers on a submarine.
0:44:58 > 0:45:03My uncle got an officer's jacket off one of the submarines.
0:45:03 > 0:45:05And his brother-in-law ended up
0:45:05 > 0:45:08wearing it ploughing fields, you know.
0:45:08 > 0:45:12Everybody going to school, you went in with something. Everybody liked to show it.
0:45:12 > 0:45:14Dermot and his uncle
0:45:14 > 0:45:17managed to swipe a naval chart from one of the U-boats.
0:45:17 > 0:45:21And ever since he was a little boy, he's kept it safe.
0:45:22 > 0:45:27It was my great treasured possession for a long time, you know.
0:45:27 > 0:45:29Showing everybody it.
0:45:31 > 0:45:34You will see that they have pencilled in every lighthouse
0:45:34 > 0:45:35around the coast of Ireland.
0:45:35 > 0:45:37This is where they seemed to zigzag,
0:45:37 > 0:45:41perhaps waiting for some ship coming their way, you know.
0:45:43 > 0:45:47To me, this was part of the U-boat really coming alive, you know.
0:45:53 > 0:45:56But there was more to this surrender
0:45:56 > 0:45:59than a formal handover at the dockside.
0:45:59 > 0:46:01As part of Operation Deadlight,
0:46:01 > 0:46:05the U-boat fleet was towed out to sea and sunk, one by one.
0:46:07 > 0:46:11U-541 was just one of over 100 U-boats
0:46:11 > 0:46:14deliberately destroyed off the Northern Irish coast.
0:46:14 > 0:46:19The idea presumably to put these boats out of reach for all-time?
0:46:19 > 0:46:21The prime driver for this frankly is the Royal Navy
0:46:21 > 0:46:24which wants to make sure that nobody gets a free supply of submarines
0:46:24 > 0:46:28with which it might attack British commerce in the future.
0:46:28 > 0:46:30An enemy unspecified.
0:46:30 > 0:46:35Operation Deadlight was a dramatic and very public display of victory.
0:46:35 > 0:46:39The decision for it all to unfold in Derry was no accident.
0:46:39 > 0:46:42It was a formal tribute to the efforts made in the city
0:46:42 > 0:46:45to help win the Battle of the Atlantic.
0:46:45 > 0:46:50Admiral Sir Max Horton chose the location for that to be Lisahally,
0:46:50 > 0:46:54marking the significance of the Foyle in the battle against the U-boats.
0:46:54 > 0:46:59Here, after almost six years of struggle, it all ended.
0:46:59 > 0:47:02For a city like Derry which had very much been the forefront
0:47:02 > 0:47:04of the Battle of the Atlantic,
0:47:04 > 0:47:09- there was some justice in this scene unfolding on its river.- Absolutely.
0:47:09 > 0:47:11The residents of Derry had been on the frontline,
0:47:11 > 0:47:15so in fact this was an opportunity for them to see the U-boat
0:47:15 > 0:47:19that had made their city important to the Allied war effort during the Second World War.
0:47:19 > 0:47:23Now that threat is going to be literally gotten rid of.
0:47:23 > 0:47:28I think that symbolism gives the residents of Derry and indeed the broader world
0:47:28 > 0:47:31an idea that the Battle of the Atlantic really is over.
0:47:31 > 0:47:34I think that must have given a real sense of finality to the people
0:47:34 > 0:47:38who were watching, and those who got to see newsreels describing it.
0:47:40 > 0:47:43This news from the frontline of the battle
0:47:43 > 0:47:45was what the world had been longing for.
0:47:45 > 0:47:49There were celebrations across the globe, and Derry was no different.
0:48:02 > 0:48:07When the word came that the war was over, everybody stopped work.
0:48:07 > 0:48:12And everybody was out through the night.
0:48:12 > 0:48:16There were dances and singing and drinking and goodness knows what.
0:48:18 > 0:48:22The King and Queen made the trip to Derry to congratulate and thank
0:48:22 > 0:48:24both the city and the Atlantic crews
0:48:24 > 0:48:26for their role in the Allied victory.
0:48:29 > 0:48:32Oh, the celebrations were fantastic!
0:48:32 > 0:48:35I mean, they were dancing in the streets. The pianos were out,
0:48:35 > 0:48:37everybody was out.
0:48:37 > 0:48:42I mean, I have that photograph of the one in our street in Albert Street.
0:48:42 > 0:48:44Even my granny was there.
0:48:44 > 0:48:46There were so many children
0:48:46 > 0:48:51and it was so exciting and the bells were ringing.
0:48:51 > 0:48:56Everybody was happy. Everybody really was happy that the war was over.
0:48:59 > 0:49:02The Battle of the Atlantic had been won.
0:49:03 > 0:49:06But there is one final secret on the seabed
0:49:06 > 0:49:10that reveals how victory came in the nick of time.
0:49:10 > 0:49:13When Germany surrendered, they were only weeks away from launching
0:49:13 > 0:49:15a brand-new fleet of revolutionary super-subs.
0:49:15 > 0:49:19Deadly vessels German scientists believed would turn the battle
0:49:19 > 0:49:21and the war back in their favour.
0:49:21 > 0:49:25The Type XXI Elektroboote.
0:49:25 > 0:49:30The team is now on the hunt for Hitler's deadliest submarine.
0:49:36 > 0:49:39They're excited at the thought of seeing this legendary U-boat
0:49:39 > 0:49:43with their own eyes and exploring the wonders of its technology.
0:49:45 > 0:49:48OK, any questions from anyone?
0:49:48 > 0:49:50Let's get in the water then.
0:49:50 > 0:49:53Shots in. Wherever you're ready.
0:49:56 > 0:50:00The sunken wrecks of only two operational Elektrobootes
0:50:00 > 0:50:01exists anywhere in the world.
0:50:01 > 0:50:04And now our team are right above one of them.
0:50:10 > 0:50:12210 feet below the surface,
0:50:12 > 0:50:15they get their first glimpse of Hitler's secret weapon.
0:50:18 > 0:50:20It was over 250 feet long...
0:50:22 > 0:50:27..and weighed more than 2,000 tonnes.
0:50:27 > 0:50:31It was faster underwater than escort ships on the surface...
0:50:31 > 0:50:36And was capable of running and outmanoeuvring any convoy.
0:50:36 > 0:50:39It could detect the sound of an enemy vessel
0:50:39 > 0:50:41from more than 30 miles away
0:50:41 > 0:50:45and could fire 18 torpedoes in 20 minutes,
0:50:45 > 0:50:48three times faster than its predecessors.
0:50:50 > 0:50:52It was the perfect naval predator.
0:51:03 > 0:51:06And her sheer scale leaves the team awestruck.
0:51:06 > 0:51:11You see just how deep and how big the hull of the submarine is.
0:51:11 > 0:51:13It's just... It's just a scale thing.
0:51:13 > 0:51:16I mean, it makes the Type VIIs look like tiddlers.
0:51:16 > 0:51:20It's just something else. It's amazing to see.
0:51:22 > 0:51:26100,000 men died in the Battle of the Atlantic.
0:51:26 > 0:51:30Historians can only imagine how many more thousands of lives
0:51:30 > 0:51:32might have been lost if the Elektroboote fleet
0:51:32 > 0:51:36had been allowed to enter the fight in significant numbers.
0:51:37 > 0:51:40The Type XXI was a game-changer. I mean, completely.
0:51:40 > 0:51:44You can see the full transition from a glorified torpedo boat
0:51:44 > 0:51:49you could stick underwater, to a totally hydrodynamically designed
0:51:49 > 0:51:51underwater fighting machine.
0:51:53 > 0:51:57It's fantastic to see such a beautiful streamlined wreck.
0:51:57 > 0:52:00It's beautiful in that it's ahead of its time.
0:52:00 > 0:52:02It was really the birth of the modern submarine
0:52:02 > 0:52:04and you just can't ask for better than that.
0:52:04 > 0:52:06It stays in your memory forever, really.
0:52:08 > 0:52:11The divers have revealed an extraordinary wreck,
0:52:11 > 0:52:13one of the legends of World War II,
0:52:13 > 0:52:16submerged just 20 miles off the north coast of Ireland.
0:52:18 > 0:52:22For Axel and Randy, the footage of the wreck is an exciting chance
0:52:22 > 0:52:25to study in detail a revolutionary secret weapon,
0:52:25 > 0:52:29one that symbolises both the deadly threat of the German U-boat
0:52:29 > 0:52:32and the wonders of its technology.
0:52:32 > 0:52:36It's something that has fascinated the people over the last 60 years,
0:52:36 > 0:52:39and here is the real thing. The actual U-boat.
0:52:39 > 0:52:41It's not just a blueprint or a picture,
0:52:41 > 0:52:47it's the U-boat mostly in its original fitting-out status.
0:52:48 > 0:52:52This is the father of all the modern submarines.
0:52:52 > 0:52:54It's a nice piece of history to have out there
0:52:54 > 0:52:57and really completes the story of the U-boat in the Second World War.
0:53:04 > 0:53:06This actually for the first time is a proper submarine -
0:53:06 > 0:53:08something designed from the outset
0:53:08 > 0:53:10to spend most of its time underwater.
0:53:10 > 0:53:13This type is designed for total underwater warfare.
0:53:13 > 0:53:16It reminds us the Allies could never really take their eye off the ball.
0:53:16 > 0:53:20They had to prosecute the campaign against the U-boat right till the very end.
0:53:20 > 0:53:23Absolutely. And from the perspective of the Allies,
0:53:23 > 0:53:26the development of the Type XXI U-boat is something they know about.
0:53:26 > 0:53:28They've captured U-boat crew members
0:53:28 > 0:53:30who have seen these U-boats under construction,
0:53:30 > 0:53:34seen them in work-ups, and they get very concerned about them.
0:53:34 > 0:53:36That raises the priority for attacking the shipyards
0:53:36 > 0:53:39and destroying the U-boats at their source.
0:53:42 > 0:53:45Throughout 1944, the Germans did everything they could
0:53:45 > 0:53:48to fast-track the new Elektrobootes into production.
0:53:48 > 0:53:49Assembled in sections,
0:53:49 > 0:53:53they could build a single Type XXI in just eight weeks.
0:53:53 > 0:53:58To the Allies it was clear. They had to destroy these deadly vessels
0:53:58 > 0:54:00before they could be deployed in the Atlantic.
0:54:01 > 0:54:04For example, in a single daylight attack,
0:54:04 > 0:54:10they were able to destroy or damage almost a dozen of these boats
0:54:10 > 0:54:11still on the building slips.
0:54:16 > 0:54:19Wave after wave of Allied bombers
0:54:19 > 0:54:22hammered the Type XXIs in the boatyards.
0:54:27 > 0:54:30Within months, nearly the entire fleet was destroyed.
0:54:30 > 0:54:33They were Hitler's deadliest U-boats,
0:54:33 > 0:54:37but only two ever made it into active service,
0:54:37 > 0:54:40and neither fired a single torpedo before surrendering.
0:54:42 > 0:54:46Now, just off the Northern Irish coast, the team has revealed
0:54:46 > 0:54:49the resting place of the last of these lethal machines.
0:54:49 > 0:54:52Sent to the bottom during Operation Deadlight.
0:54:58 > 0:55:02History, of course, is full of what ifs, but the question I'm going
0:55:02 > 0:55:06to ask you is - if the war had been prolonged for whatever reason
0:55:06 > 0:55:10and these boats had really taken a hold and their numbers had grown,
0:55:10 > 0:55:14it would have potentially had a disastrous effect on the ongoing campaign?
0:55:14 > 0:55:17Had the conflict lasted one or two months longer,
0:55:17 > 0:55:21a fairly large number of these boats would have appeared in the Atlantic.
0:55:21 > 0:55:27Certainly, the sinking figures would have risen to unheard dimensions.
0:55:30 > 0:55:35All the historians say it wouldn't have caused the war to be lost,
0:55:35 > 0:55:39but it certainly would have made it a hell of a lot longer.
0:55:39 > 0:55:42You go away from that wondering what might have been.
0:55:42 > 0:55:46And the Battle of the Atlantic would have been a much longer
0:55:46 > 0:55:49and even more bloody conflict.
0:55:52 > 0:55:55Ian's mission to map the lost wrecks of the Battle of the Atlantic
0:55:55 > 0:56:00has unlocked the story of history's longest, most epic naval campaign.
0:56:01 > 0:56:07That dive was just the best way to end what has been a real challenge.
0:56:07 > 0:56:10So it makes it all utterly, utterly worthwhile.
0:56:10 > 0:56:12It's just fantastic, man, you know.
0:56:12 > 0:56:15And the team has succeeded in uncovering forgotten wrecks,
0:56:15 > 0:56:21revealing technology and tactics of the mightiest of sea battles.
0:56:21 > 0:56:23Where else would you rather be?
0:56:26 > 0:56:30It's sobering to think all this went off - on a lovely, calm evening like this -
0:56:30 > 0:56:32it's sobering to think of it all happening out here.
0:56:32 > 0:56:34There's always a story.
0:56:34 > 0:56:38The waters off Northern Ireland's coast have at last revealed
0:56:38 > 0:56:41the secrets of the forgotten wrecks on the ocean floor.
0:56:43 > 0:56:48Even after more than 60 years on the seabed, they still are able to
0:56:48 > 0:56:52give off some secrets, there is still something we can learn.
0:56:53 > 0:56:57The wrecks tell the story of 37,000 Allied sailors,
0:56:57 > 0:57:0436,000 merchant seaman and 30,000 German submariners.
0:57:04 > 0:57:08Men who all lost their lives in the Atlantic in the fog of war.
0:57:08 > 0:57:11And at the heart of the story - Derry.
0:57:11 > 0:57:15Transformed by its vital role in the Battle of the Atlantic
0:57:15 > 0:57:18and in the victory of the Second World War.
0:57:18 > 0:57:21A city with its own forgotten history.
0:57:21 > 0:57:24Its river filled with warships,
0:57:24 > 0:57:27home to America's first European military base,
0:57:27 > 0:57:31to an underground command bunker
0:57:31 > 0:57:34and home to the fight against the deadly U-boats.
0:57:38 > 0:57:42The men and women of Derry met the challenges of war head-on.
0:57:43 > 0:57:45Theirs is a city with a wartime heritage
0:57:45 > 0:57:49that deserves to be remembered and celebrated.
0:57:50 > 0:57:52Trying to keep the memory alive, I think
0:57:52 > 0:57:57is important because when traces of all of this are gone,
0:57:57 > 0:58:00then something from our history
0:58:00 > 0:58:04and something from our collective memory goes as well.
0:58:05 > 0:58:09Only fragments of this story remain. They should be treasured.
0:58:09 > 0:58:13The priceless wartime heritage of an historic city
0:58:13 > 0:58:15at the heart of an epic conflict.
0:58:45 > 0:58:48Subtitles by Red Bee Media Ltd