HMS Dasher, resting in 170m (555ft) of the world's worst water

By Alex Deas, Gary Allison and Mark Reeves

Our adventure began in January 2000, driving from Orkney to Edinburgh. The windscreen was playing a video in fast forward, the rain that had fallen on the road had become black ice before being covered with half an inch of snow. The conversation turned to calculated risks, and trimix.

Mark: "We must do some really deep dives this year, but for a cause and not just to touch some fishing skiff on the seabed. Kevin, you're Scotland's expert on wrecks, what is out there?"

Kevin: "It depends on what you like. Alex, tell me what wreck is your idea of the best dive?"

Alex: "Without doubt, HMS Hampshire. To me, the Hampshire is a better dive than the Titanic would be: the Hampshire is such a terrible tragedy, compounded by secrecy and conspiracy, against a backdrop of great heroism."

Kevin: "OK, if that is what motivates you, then the HMS Dasher is definitely what you are looking for. It's a British aircraft carrier sitting upright in 170m (555ft) of low visibility tidal water off Arran. Of course, that deep it has never been dived and has a compelling story: huge loss of life, the Government covered it up to the extent they never even had the decency to tell relatives where their husbands, sons or brothers died or were buried - they are still in unmarked graves. The vessel sank in 8 minutes, and not through enemy action: it was converted from a merchant vessel in just 3 months in a US shipyard, but the workmanship was so poor as to be criminally negligent - 20m (60ft) cracks in the hull opened up in rough seas. A US shipyard worker, when he saw some Royal Navy personnel, burnt the letters RIP into a steel plate, looked at them and then walked away. The man you need to speak to is John Steele. He is a real gentleman, who has researched the wreck for 11 years. I'll set up a meeting for you."

A few weeks later, Kevin Heath sat with Alex Deas as guests of John and Noreen Steele. Eating High Tea in their house in Ardrossan, looking out towards the mountains of Arran, out over the wreck site, the story unfolded. Kevin asked questions which brought out John's background: such an unassuming and modest man, but with a fire inside that burned strong. Once, John had saved the lives of hundreds of people on a ferry on which he was a passenger when it caught fire, and then campaigned for improvements in ferry safety. Later, John had heard a rumour among old people talking about a terrible disaster. Eleven years of tenacious research later, he published the book, "They were never told, the tragedy of HMS Dasher", and set about to inform all the relatives he could contact what had happened. John campaigned unrelentingly for a memorial to those who died.

The HMS Dasher story itself is also written in acts of courage. When the Dasher sank, in just 8 minutes after an explosion, the sea boiled like a champagne bottle as the 75,000 tons of diesel fuel and 20,000 tons of aviation fuel bubbled to the surface. Brave people were in the freezing water, such as Commander Lane, who swam from lifeboat to lifeboat tying knots in the ropes so those in the water, covered in oil, could climb to safety. Others swam out, so those who could not swim could get the life rafts nearest the ship. Suddenly calcium flares ignited the fuel, scalding to death the mass of humanity alive in the water that day, water which seconds earlier had brought cold to their very bones.

Many gave their lives to save others: there were many heroes that day, 23 March 1943. Two coasters risked the flames to pick up survivors while larger Royal Navy vessels watched. Those that survived seeing their friends die in such horrific circumstances were ordered not to speak of the events to anyone, leaving them without any relief from their deep emotional wounds. There were a few funerals, then all the other bodies were buried in unmarked graves without any respect, any funeral, any notice to the ones who they loved and were loved by. None of the heroes that day received recognition: no medals were issued, as HMS Dasher never existed!

The emotional picture behind this wreck became the predominant issue. This dive had a real purpose: to lay a memorial on HMS Dasher to the 379 who died with her, ensuring the suffering there would not be forgotten. The dive team worked closely with John Steele throughout the preparations to ensure the maximum respect for the wishes of the relatives.

Dive preparations got underway. Alex reported his previous experience freediving off Arran in summer: very low visibility in water infested with jellyfish: this dive was going to be challenging. Noreen Steele confirmed that during the summer the sea was a raft of jellyfish, miles wide. In the winter, the storms were without interval.

What was needed for a 170m (555ft) cold water dive? Abyss dive planning software revealed that if it took 10 minutes to descend with 10 minutes bottom time, it would require 20 bottles of gas. This was not practical for one diver to carry. What alternatives were there?

Both Mark and Alex agreed this was a simple dive on a rebreather: in theory you just fill up a 7ltr cylinder with heliox and the rebreather takes care of everything else, so long as it does not go wrong. The dangerous region with a rebreather was reportedly near the surface. Thus emboldened, both divers enrolled on the best rebreather course available, bought a Draeger Dolphin and Buddy Inspiration rebreather each, and set about getting in as many hours experience underwater using them as possible.

During training on the rebreather, the truth was clear: it is true that trimix diving on a rebreather is simpler than open circuit, but was very risky. Any failure meant death. Several serious incidents occurred during the intervening months. After a series of these "learning experiences" on the Inspiration, it was nicknamed, the "one breath from death machine". Instructors advised getting 100 hours of experience with the unit underwater before doing any serious decompression dives, yet fatal accidents with rebreathers still occur with experienced users. Interest in doing this dive the clever way, on open circuit scuba, began to grow.

To dive on the Dasher with open circuit equipment, a new ethos was required. Instead of a conventional expedition, an alpine like fast assault was needed: the minimum number of people, the minimum amount of redundant equipment, as light weight and fast as possible. Alex, the expedition organiser, was also an ice climber, familiar with alpine methods. Would they transpose to diving?

By increasing the descent rate to a minimum of 30m per minute (100ft /min) with ten minutes bottom time, having every diver dive solo, by using only a 20% gas margin and no decompression margin, the number of cylinders would be reduced. If the dive plan was no deeper than the flight deck at 140m, it would reduce the amount of gas to 7 large cylinders: this could be carried by one diver, just.

The team was formed:

Mark Reeves, bottom diver, on open circuit to lay a memorial on the Dasher. Neil White's expertise was critical: to drop the shot onto the shallowest part of the flight deck he could find, but if the shot missed the wreck and went to 170m, Mark would dive the 170m. Safety divers would bring extra cylinders if the dive exceeded 140m.

Gary Allison, bottom diver on Open Circuit Scuba to confirm that the memorial is in place, with a maximum planned depth of 140m.

Alex Deas, deep standby and safety diver on an Inspiration rebreather with full OC emergency bailout, to go to any depth if a signal buoy came up, and would in any case meet Gary at his deep stops to ensure his safety throughout decompression.

Tim Claridge, safety diver, would meet Mark at his first stops and ensure his safety throughout decompression.

All members knew each other, had dived with each other and had the respect for each other as excellent solo technical divers able to handle any situation calmly. Each made judgements based on a thorough understanding of diving technology, but each with different styles. For example, Tim ascends from deep trimix dives by launching a lift bag with 30m (100ft) of tape attached, waves bye bye, and after a short delay, shoots up as if on a fast lift to his first stop - this is safe only with excellent buoyancy control. Alex makes a lot of his own equipment and does ice dives without a hood, without any apparent ill effects. Mark and Gary too have their own inimitable styles. Each joke about each others methods, but no criticism: at this level each know the facts, each know the implications, each know the risks intimately.

The date was chosen: 28 June 2000. The Loyal Mediator was chosen as the dive vessel: this is an ex-Royal Navy vessel, able to sail in severe weather.

A crew? We bought the Mediator in January, but it had been laid up awaiting plans for a refit. None of us had real experience with her. The decision was made to hire Royal Navy auxiliary reserves who had 20 years of experience skippering this class of vessel for the journey from Orkney to Ardrossan. On the day we sailed, a Force 6 storm blew in: not a problem for the vessel - we had already been out in her in a Force 10 to 11. Just in case, the European Technical Dive Centre's skipper Neil White, was on the bridge.

Captain Ken made an underwhelming start when he smashed the Mediator into the pier, buckling plates. After a quick trip into the Pentland Firth, he decided to return to port to explain that he only sails in flat calm and then jumped ship, along with the rest of the auxiliaries. The dive team call an emergency conference: Neil says he is sure he could do a better job than Captain Ken, Tim who doubles as the ship's engineer says, "Well, there is a job to be done, lets do it", Mark, Gary and Alex all agree - the Mediator sails. So straight out into the Force 6, with 2m (6ft) of green water coming over the bow, waves behind to the height of the bridge - how much can it take? Stories were retold of the last time it was out, with water sitting on the mast, helped put things into context. We leave Dad's Navy and go.

After rounding Cape Wrath, the voyage settles. Sights of killer whales breaching, basking sharks, dolphins and porpoise set the scene for a trip that is starting to look good.

Arriving in Ardrossan, the dive team agree to dive a supposed submarine laying in 60m (200ft. After searching the entire wreck area, the object reported is identified on sonar and recorded on the GPS. It is not clear if the object is a wreck at all: the subsurface echoes do not seem right. It is agreed that Alex goes in first with his trimix rebreather and sends up a buoy if it is a wreck, so others do not waste time going down unless it is worthwhile. It is obvious the visibility is poor, and the sea is full of stinging brown jellyfish.

Alex redoes his checks, leaps in over the dive ladder, and shortly afterwards comes up on his bail out gas asking to be picked up. He is holding his mask in his hand and rinsing his face in the sea. He had a leak which caused the lime in the rebreather to turn into caustic water stinging his nose and mouth. Pouring the fluid out on the deck etches the paint. Alex sets about tracing the problem and cleaning everything.

Mark goes in, followed by Tim and Gary. Fifteen minutes later, Mark comes up reporting that he hit the bottom unexpectedly: there is 6 inches of visibility, and the bottom is the same colour as the water. The team assume this will be the conditions on the Dasher dive.

Mark described that even a Dublin Bay Prawn was covered in mud! He poked around and found the "submarine" was in fact a lump of rock, covered in mud, definitely not a wreck. Alex was about to jump back having traced the fault, washed everything and refilled the lime, but when Tim confirmed it really was a mound of mud, everyone got back on board and started preparing kit for the next day. All divers had jellyfish burns, with Gary burnt around the lips, Mark on the arms, Tim had a jellyfish on his back, Alex had bits in his hair. After washing off in sea water, vinegar was brought out - the only cure.

The day of the Dasher dive, 28th June, had arrived. The memorial had been dedicated in Ardrossan. It now had to be laid.

Neil White spent hours criss-crossing the dive site to find the shallowest part of the flight deck: the Dasher lay on a slope, which at its shallowest was only 160m to the seabed, and 130m to the flight deck. The shot was dropped with depths marked on the rope, configured to ensure the shot stayed vertical. The decompression trapeze was set with provision for it to float free if the tide picked up.

Each diver was using a different gas mix and mixed their own gasses. Bail out and contingency tables were printed just prior to the dive, laminated, copies left with the safety divers, and the dive began. The primary dive plan, used 60% He, 9% O2 for the bottom gas, carried in twin 15ltr back mounted tanks. Travel gas was EAN32 to EAN36 Nitrox, carried in two 300 bar cylinders under the left arm, decompression was on EAN82 Nitrox (82% Oxygen) in a further two 300 bar cylinders on the right arm. Gary managed to squeeze in an extra tank between his twinset, and an argon cylinder.

The dive plan was for Mark to go in, with Gary 45 minutes later. Tim was to join Mark at his 20m stop where the CNS percentage was starting to build. Alex was to wait until Gary was at his deepest stop before going in, in case a buoy went up. Any buoys meant Alex was to bring down extra gas to whatever depth the diver was at by using his rebreather.

All divers were assisted to kit up. The equipment for each diver weight hundreds of pounds: the divers could scarcely stand.

Mark went in, forty five minutes later Gary went in, the dive ladder was bolted into position - safety divers would have to vault the ladder, Tim leapt in, Alex looked for buoys, then at the agreed time went in. Everything was executed to perfection: exactly on time, the shot was at exactly 131m, all equipment worked perfectly.

Three hours later, Mark was back on deck. His face was transformed. He sat describing the silence, the stillness, the awe of being on that flight deck laying the memorial where so many had died. The visibility on the bottom was between 10ft and 15ft because of the darkness, but the torch would pick out items 50ft away. Fishing net covered the superstructure and bundles lay on the deck itself.

The bottom temperature recorded by Mark was 5C.

Gary was now back on deck, describing how his torch had picked out the memorial plate, laid neatly on the flight deck away from the shot so it would not be dislodged when the line is retrieved. Everyone thanked Neil White for his superb handling of the Mediator throughout and putting the shot in exactly the right place.

The immensity of what had been achieved sank in. Laying the memorial on HMS Dasher had required the deepest wreck dive ever in cold water on open circuit scuba. The hazards of low visibility, of freezing equipment, of manipulating simultaneously dry suit and buoyancy wings, had pushed the envelope. Yet, the dive itself was eclipsed by the emotion of the Dasher itself and the empathy with those whose suffering had started in that same place with such tragedy, such sorrow.

John and Noreen Steele were on the Loyal Mediator throughout the dive, laid rose each at the site on behalf of the relatives of those who died. John started contacting the relatives to confirm the divers had all returned safety and the memorial was laid. Letters of appreciation from the relatives started to pour in the very next day.

Pictures:

Choice of 20 pictures from the library of the dive, bottom divers kitting up, Alex going in with his RB, Mark Reeves kitted up with the memorial, divers mid air, good pictures post dive, on deco, the Dasher afloat, some of the brave men lost.