Donegal Coast Waterworld

'There's more war time adventure ahead,

'this time off the Donegal coast.'

We're just leaving Downings,

heading out on a beautifully flat summer sea into the wild Atlantic.

We're looking for a U-boat that sank in the First World War

and we're in the company of two technical divers.

'Alan Wright and his wife, Freda, get a high from going deep.

'We're charging more than 30 miles offshore to the U-89,

'a wreck Al knows well.'

For me, I'm into exploring sub wrecks and submarines around this area.

Unfortunately, to get to the better shipwrecks,

the ones in better conditions, you have got to start to go deeper.

'We arrive on site blessed by fabulous weather.'

Just put the buoy on there and we'll lie clear.

It is a perfect day from a whole number of factors.

To do this dive in this location,

a wind was going to blow your plans away, wasn't it?

That's right, you've got to have so many things right.

We've got perfect conditions, plenty of light.

The unknown is the underwater visibility,

but it does look pretty clear

so with a bit of luck the visibility will be good as well.

Can't believe the weather, it's just...

Well, it's incredible really.

'The U-boat is 60 metres below us,

'an extreme dive requiring skill, experience and technical know-how.

'Freda and Al will breathe mixed gas - oxygen, nitrogen and helium.'

IN SQUEAKY VOICE: Helium check, five, four, three, two, one.

THEY LAUGH

'It's used to beat the narcotic effects

'of breathing nitrogen at depth.

'Al's using a computer controlled life support unit

'called a rebreather, programmed to deliver precise gas blends.

'Critical because even oxygen can turn poisonous in the deep.'

Tell me about the checklist.

It's a 20-point checklist I've got to do before I get in the water

for this rebreather because it is a life support equipment.

I follow the checklist, turn the valves on when it tells you to

and do the manual checks.

It takes about five minutes or so, that's what I'm doing at the minute.

'And as if he doesn't have enough to think about,

'Al's going to film the dive for us.'

OK, you're clear to go.

It's going to take just about two minutes to descend

60 metres down that shot line onto the wreck of U-89.

But they only get 24 minutes down there

before they have to come back up.

And after that, it's a full hour, coming up slowly,

stage by stage, back into fresh air and this glorious day up here.

You can actually just see them disappearing.

As soon as we get in,

we start descending down the line towards the wreck.

If there's current there, you might have to swim

and work a bit harder to get yourself down the line,

monitoring your gauges on the way down as well.

You can see the whole wreck and that's just wow, really,

that's just fantastic.

Each time you do the dive, even though you might have done the same

wreck ten times, it is completely different every time you dive it.

You'll see different marine life, different visibility,

different currents, it's just so different, so vast.

She sailed from Germany on 5th January 1918

to go and attack convoys in the north of Ireland.

She was spotted on 11th February by a British reconnaissance aircraft

and they basically homed in the destroyers to search for her.

She actually surfaced in daylight on February 13th 1918,

right next to HMS Roxburgh.

And Roxburgh spotted her

and basically rammed her just after the conning tower.

You can see the engines just sitting out there, the twin diesel engines.

Swam forward to the conning tower and it was full of primrose anemones.

It was covered in anemones, of every colour you can imagine,

just like a carpet really, everywhere.

We can see the conning tower hatch open, and the periscope standard,

where the periscope went up and down.

Then we dropped round the side of the conning tower with the current

and drifted slowly down to the deck gun.

The deck gun there is a 105 mm deck gun that was used

really during the war, they would surface and shell the convoys.

You see the gun sitting on top, just pointing,

almost ready to shoot really and you can just imagine, you know,

that these guys have gone away and they're going to come back later.

It's just incredible really.

Then we went to the torpedo loading hatch, and we looked in.

That hatch is at an angle to get the torpedoes in

because they're six metres long.

Lo and behold, down there in the bottom

you could see the two torpedoes,

lying there with the fins and the propeller.

That thing was designed for one purpose - to sink ships.

Those torpedoes just bring it home to you,

and a crew of 44 drowned in that vessel.

We're out here in the blue wilderness far from the shore,

and the divers, by my reckoning,

will just have ended their dive and be heading up for the surface.

It's kind of a privilege being out here

because most people back there on land will never get to be

32 miles from the shore in a very small boat,

and to spend the day in the company of people who...

I suppose they put their life on the line in search of adventure.

It's quite something.

'This is perhaps the most dangerous time, ascending from the deep.

'They must stop and wait at stages

'to avoid every diver's worst nightmare - the bends.

'To avoid it, Al and Freda must get rid of the nitrogen

'that's been stored in their blood stream,

'and that means hanging around,

'breathing oxygen-rich air nearer the surface.'

There they are.

Back up from the deeps.

They look happy.

Good dive, Al?

Yes, very good.

A little bit dark, but not bad there at all.

What's the light penetration on the wreck?

You're talking about 200 feet down?

Yes, 200 feet down you're getting natural light down there.

It's pretty good really.

It's about 15 metres, about 50 feet, is all the visibility.

Whenever you're in the office or doing stuff

that you don't want to be doing, is this what drives you?

-Oh yes.

-Yes, absolutely.

-Definitely.

-Especially days like this.

The amount of ship wrecks we've got out here,

when we get the weather like this, it's world-class diving out here.

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