Mark Powell leads an intrepid band of technical divers half way across the world to dive the wreck of HMS Hermes - the world's first purpose-built aircraft carrier. Sunk during an onslaught from Japanese Zero Fighter Bombers during World War 2, this rarely dived historic wreck is a wreck diver's dreamÖ


There was no rush to get up next morning so we enjoyed a leisurely breakfast at about 9.00 am. There was no rush as some of the equipment had not yet arrived. We had shipped sofnalime, rebreather cylinders and a booster pump and - despite shipping it a month in advance - it had only cleared customs the previous day and was being transported across the country on the day we arrived. The crate arrived at the harbour gates at 7.00 am and we were still waiting for it to receive permission to enter the harbour at 1.00 pm

As we were sitting in the harbour waiting for the kit to arrive we had a constant stream of buses arriving and off each bus a group of school children would get off and come and look at the boat and us on board, rather than tourists we felt more like tourist attractions. In the mean time we did what little preparation we could. I checked my rebreather was undamaged but without sofnalime or cylinders there was little other preparation that could be done.

Kit arrives at 1.00 pm and itís like Christmas, packages and boxes come tumbling out of a van. Some contain brand new cylinders for the rebreathers straight from AP in the UK, others contain the Haskell booster pump and panel, finally there are 20 kegs of sofnalime. Once the van has been unloaded the first priority is to build the blending panel and booster pump so that the

rebreather cylinders can easily be filled. A couple of hours later and we have a working blending panel and full diluent and o2 cylinders, stages are rigged and we are ready for a check dive.

We finally head out of Trincomalee harbour and can truly appreciate the size of this natural harbour, what we thought was the extent of the harbour turns out to be just one part of the harbour. As we steam out we pass the submarine boom nets which are still pulled across the harbour entrance every night. Half an hour later and we are at a site called pigeon rock, this is a shallow reef with depths of between 10m and 20m. We all kit up and are taken out to the dive site in a fast rib. Dropping down we can see that the vis is reasonable but not exceptional. The marine life is similar. At least it is ideal for a check dive and we can all fine tune our weighting.

I'm happy to find that with a stainless steel backplate and 4kg at the top of the unit I am perfectly weighted. After a few minutes looking at the reef I run through a few drills to make sure my bailout works, stages can be removed and replaced and everything is generally working. Check dive successfully completed we head back to the live aboard. Although its been a frustrating day and we have only done the one dive at least we are all set up and ready for the rest of the week.

The first priority was to build the blending panel and booster pump for the rebreathers


Friday is to be the first day of wreck diving. Today we will be diving the MV Cordiallity, a cargo ship that was carrying limonite. Limonite is a mineral mined in Sri Lanka and used in the production of iron, at least that what the internet claims! The ship was a casualty of the civil war and was sunk in 1997 by the rebels. Eight Chinese sailors were killed when the vessel was attacked and sunk. The ship is in 18m of water and the highest point, the bows and a crane on the foredeck break the surface making it a very easy wreck to find.

We drop in on the bows and the size of the wreck immediately hits you. 18m high bows stand up proud from the bottom. Just back from the bows the hull has been cut open where the wreck has been salvaged. From just behind the bows right the way back to the engine room, in other words the entire cargo hold area, the hull has been sliced vertically on order to cut the material of the hull into smaller sections ready to be salvaged. On the port side, just in front of the engine room one of these sections has fallen outwards and is lying on the sea bed but the other sections have all fallen in to create a tunnel effect along much of the length of the cargo holds. This makes it easy to swim under the collapsed inward sections, safe in the knowledge that an exit is always just ahead.

These enclosed spaces are populated by a whole range of marine life including box fish, banner fish, grouper and many other fish. As you make your way towards the stern you reach the stern superstructure and the entrance to the engine

room, this huge space is definitely the highlight of the wreck. The engine room is on 3 levels with the engine and auxiliary equipment still being easily accessible as are a number of side rooms which served as tools stores and workshop. Tools still hang on their places on the wall. The only downside to this dive is that the visibility is not as good as we expected, only a couple of metres in places although inside the wreck and especially in the engine room the visibility is much better. Light streams in from above lighting up most of the engine room.

After the dive two of the crew head off in the fast rib to check out another wreck that has been suggested by some local fishermen, despite a two hour round trip the wreck turns out to be very small and stands up only 2m from the seabed and so we decide to do the second dive on the same wreck as in the morning. The visibility around the wreck has improved slightly and it allows those divers who didn't find the engine room another chance to explore it. It also gives me a chance to do a full circuit of the wreck, work out the exact shape of the wreck and sketch the layout. I finish off the dive with another look around the engine room and find plenty of other opportunities for exploration. The engine room alone on this wreck is well worth the dive. After the second dive we have a late lunch and start the steam south to reach HMS Hermes. The plan is to steam through the afternoon and early evening and moor near the wreck ready for the first dive in the morning.


The plan today is to dive the Hermes, the whole reason for the trip. The day doesn't start well as we have two sets of marks for the wreck and there doesn't seem to be any sign of the wreck around either point. The marks are close together and so we know we are in the right area but it takes a significant amount of searching before we finally locate the wreck. There is a lot of tension onboard but once we know we have found it the tension turns to excitement.

As we drop down the line we can see that the visibility is excellent, it drops a little after 30m but is still impressive. The shot is right on the wreck, near the flight control tower and almost on top of one of the guns. After we tie in the shot It's time to explore the wreck. She lies on her port side and I head along the deck towards the stern. The shot is at the forward end of the flight control tower so I can see the main part of the hull on my left and the tower on my right.

As I get to the end of the tower I come across the second of the main guns. From this point onwards I am swimming along the side of the hull where the flight deck should be exposed but in this area the wreck is almost inverted so it is difficult to see the scale of the flight deck. I pass another main gun before getting to the stern. The starboard prop is standing clear and makes a very impressive sight. The port side prop is partly buried in the sand and is only partly visible. I make my way slowly back along the wreck until I get back to the shot and have a look around this area before reaching my planned bottom time of 45mins. We all have similar plans and so the whole team ascends together with smiling faces all round.

The delay in finding the wreck together with the surface interval required in order to make a second dive feasible means that we elect to do the second dive on another wreck. This is known as the boiler wreck for reasons that were soon to become obvious. Again we had approximate marks and so the first step was to find the wreck which sits in just 10m of water. The first position didn't seem that

promising and due to the heat and the fact that I was only expecting a very broken wreck I elected to jump in anyway, even if it ended up being a scenic dive. Some of the others decided to carry on searching in the boat, after 30mins of scenic diving I was beginning to think I had made the wrong decision until in the distance I saw the unmistakable shape of wreckage. Through blind luck I had managed to stumble across the wreck despite being 200m from where we had jumped in. I realised that this wasn't just broken wreckage but was the remains of a huge ship.

The fact that we were only in 10m meant that i still had plenty of time to explore the wreck and it wasn't until about 20mins later that the boat found the wreck and the others joined us. Five enormous boilers dominate the wreck with the remains of two engines behind. Huge crank shafts and piston heads still visible. Two prop shafts led away from the engines, in places still in the prop tunnel, back to the large stern section. Forward of the boilers the bows were almost intact but lying on their starboard side. This was clearly a very large ship. The layout andy lack of armour or guns implies it was a cargo ship. The loss of a ship of this size would almost certainly have been documented and it should be possible to give this wreck a more concrete identification than the boiler wreck.

Dinner that night was filled either the excited chatter of some very happy wreck divers and after dinner I pulled out my laptop and we went through all the pictures I had of HMS Hermes identifying any features we had spotted that day and identifying target areas for the following day. The discussion of the wreck branched out into some of the history of the ship and her sinking and i gave an overview of her history to those members of the group that were less familiar with the story. I believe that it is much more enjoyable to dive on a wreck when you appreciate the story of the ship and of the men who served and in this case died on her.


We are up early in order to five and then have sufficient surface interval for a second dive. The plan for this five is to explore the flight control tower and then swim forward to the bows. With the shot midships it makes it easy to go off in either direction. We swim along the control tower that lies along the sand, looking in to the intact bridge area where gauges, complete with glass, are still present as well as a range of other fittings.

Above the bridge area is a large circular structure that looks like a mini helipad. I assume this must have been a mounting point for some sort of instruments but interestingly this looks different to the structure shown in the pictures I have of Hermes. Either the structure shown in the pictures was mounted on this circular platform and has fallen off or possibly it was changed when the ship was retorted. A review of pictures before and after her refit should help to solve this mystery.

We swim back over the control tower and back towards the bow. The anchor chains as well as the anchor are clearly visible. At the bow the recount has come away from the bow and its possible to see right into the foícísíle of the ship. A row of toilets are clearly visible together with an intact lamp fitting in the ceiling. Beyond this it is possible to see down through several deck and light penetrating through the hull shows that there is a hole in the hull a couple of decks down.

Looking in through these holes gives a clear indication of the layout of the forward part of the ship. I can't help but think of the men who served, and in many cases died, on this wreck. The wreck serves as a museum to this unique piece of history as well as a monument to the men who perished on her. I hope that anyone who dives this wreck takes the opportunity to remember these men and treats the wreck with the respect it deserves. The visibility on the ascent is spectacular and I can see divers spread out along the length of the shot line.

After a 50m dive we all want a good surface interval before thinking about a second dive. A leisurely lunch is only interrupted by a pod of dolphins who have stopped by to investigate our boat. At least 6 dolphins swim around the boat until they get bored of watching us watching them and swim off again.

By now I have started to get a good feel for the wreck and decide to start trying to do a sketch map on the second dive. I fill in the details of the bows and control tower from the first dive and now want

to fill in the details of the rear of the ship. We drop onto the middle section of the ship and i take the opportunity to correct a few detail of the control tower part of my sketch. I then start to swim back from the control tower towards the stern. It is clear that there is a gap between the main deck and the control tower, as if it has broken away and is just lying next to the main deck. Behind the control deck I can start too see what has happened to the rest of the ship. The hull has almost inverted and the flight deck, which rather than being an integral part of the hull in the rear section is effectively just a platform mounted over the main deck, has holder down under the rest of the wreck.

Further back, where the hull is more on its side than inverted, the flight deck is more exposed. At the very stern the main deck was very open with no hull between the main deck and the flight deck. In the area the flight deck has come away from the wreck and forms a debris field next to the stern. From here we follow the hull up to the starboard prop which stands up above the hull. The propshaft leading forwards and disappearing into the hull is also visible. From here I swim back along the hull, trying to get a clear picture of the state of the hull before arriving back at the shotline amidships.

An uneventful deck is marked only by the fact that there seems to be a small boat buzzing back and fore around the dive site, from the outline and the single engine I can see that it is not our safety rib which is also on station. On surfacing I am confronted with a scene reminiscent of the film Zulu. A line of 20m local fishing boats faces me, all in a line. It's clear that as they know we are diving the wreck they have taken the opportunity to use our shot to position themselves across the current just to the stern of the wreck. This is no surprise as on every dive we have seen an amazing variety of fish. Large tuna, grouper and jacks flock around the wreck as well as a huge number of other fish. Some of these are an impressive size with one grouped being considerably larger then me. Some of the tuna are also a very impressive sight.

As well as the fish a huge variety of coral and other marine life means that there is significantly more life on this wreck than on the vast majority of reefs. The combination of the history of the wreck, its size and state of preservation combined with the incredible level of marine life means that this wreck is in a league of its own.


I'm really starting to get a feel for the layout of the wreck and the location of some key points. One of the other divers has some specific things on the wreck that he wants to see so we swap around buddy teams and I lead him forward towards the bows to see the specific points of interest he wants to see. We pass the shell hut next to the big gun across the forward deck passing the anchor chains until we get to the bows. Here we can see the clear shape of the bows and the gap where they have partly split open. We swim around the bows until we are on the hull and spot the two great starboard anchors still in the storage recesses as the ship was making way when she wad attacked. Drifting back over the hull we drop back onto the deck and drift back to the control tower where we spend the last part of the dive exploring this fascinating area.

We have been in contact with another ship that is doing side scan surveys in the area. They have found what looks like a large wreck in 24m. It stands 10m proud of the seabed and is split into two sections about 10m apart. The suspicion is that this may even be HMS Hollyhock, a flower class Corvette that was sunk at the same time as Hermes. The marks they give us are about 18 miles from Hermes so we decide to take the fast rib and try to locate this wreck. The twin 200 HP outboard engines make this a very easy journey over the glassy sea.

As we get to the position on the GPS we slow the rib and allow the depth sounder to catch up. The scatter clears just as the GPS tells us we are directly over the wreck. The sounder shows a depth of 12m but we know the seabed in the area is 24m. We have hit the wreck directly on the first try without any need for a search. I feel that familiar feeling of excitement that only comes when you dive a wreck for the first time.

As I drop below the surface the wreck immediately comes into sight. I land on what is clearly an upturned hull and as I drop down the side of the wreck I can see sheer walls of steel extending down

to the sea bed. This part of the wreck is clearly intact but upside down and almost none of the superstructure is visible to give any hint of identification. I swim along the wreck and find a number of small holes where I can look inside. Through one of these I can see right through to the other side of the wreck where there is a huge hole that would allow easy access to the interior.

I swim on and reach the bows and on around these and make my way along what I now know to be the starboard side until reach the hole I saw previously. I carefully look inside a huge hole, this is confusing as the open space inside doesn't correspond with any area I would expect to see on a Corvette. It looks more like a cargo hold.

I carry on along the starboard side until I come to the break. This also allows me to see into the ship and I find what looks like a cargo hold. This is no flower class Corvette but looks like a cargo ship. Just within sight is the second part of the wreck, the stern section. As I swim over to it I can see that this section is almost upright with just a slight list to starboard. Another cargo hold is visible and as this section is upright the open top of the hold let's in plenty of light. I swim through the empty cargo hold and on along the wreck, passing another hold before reaching a small superstructure at the stern. This has been enough to identify the type of ship and so I start my ascent.

The return trip to the live aboard is marred by engine trouble. Initially we think it is blocked or contaminated fuel but once the live aboard comes and gets us the rib coxson eventually realised with some embarrassment that the fuel gauge is faulty and we simply ran out of fuel. The rest of the group do a second dive on Hermes but discovering a new wreck and getting marooned at sea is enough excitement for me so I have an extended surface interval and a doze in the shade.


One of the engines on the boat is playing up and combined with my description of the wreck I dived yesterday the decision is made to steam north and dive this wreck on the way back to Trincomalee. I'm looking forward to having more time to explore this wreck after my brief reconnaissance dive yesterday. Unfortunately the vis is not as good, a mere 5m. I didn't see the engine yesterday, a key factor in identifying the type and age of the ship.

As we drop down the line I notice it has been dropped right in the break between the two sections. On a hunch I head towards the stern section. Here I spot the exposed broken open cargo section I noticed yesterday my buddy and I swim into this section. As we look through the bulkhead into the next section I can see what is clearly a boiler. We swim through to the next section. Here we can see two boilers, one of the other divers later tells me that he saw another boiler partly buried in the sand outside the wreck. Behind the boilers the engine room roof has collapsed in which made it difficult to identify the engine, luckily my buddy is a mechanic who spots what might be a part of a steam turbine engine but there is not enough to be conclusive. I also spot what looks like a Bakelite light switch.

Beyond this there is an unusual feature, at first glance it looked like heavy duty electrical wiring but may have been piping. Beyond this we explore the superstructure above the engine room which stretches back towards the stern. Yesterday I had noticed superstructure on the other sections in the

midships area, this is interesting as cargo ships before the 1930s tended to have the engine room and superstructure midships with cargo holds fore and aft whereas engine room and superstructure at the stern is a feature of more modern cargo ships. This wreck appears to have some superstructure and presumably the bridge midships with a smaller superstructure and the engine at the stern. Could this even be the British Sergeant? It will take further research to identify anything more about this wreck.

As we steam back to Trincomalee I reflect that we have dived a truly world class wreck, the historical background behind HMS Hermes, the fantastic state of the wreck and the abundance of marine life set this wreck apart. We have also dived another three very impressive wrecks, two of which are unidentified and one of which has possibly never been dived before. In addition we still have several other marks, any of which could be the other wrecks that went down in the same attack as HMS Hermes. Overall it has been a fantastic expedition although there are still plenty of loose ends that still need to be tied up.

In true expedition fashion there have been numerous challenges along the way; delays with bureaucracy, delays finding wrecks, running out of fuel, engine problems and other minor problems but that's an inherent part of expedition diving as opposed to holiday diving.

Further research will be required to identify the British Sergeant

Getting the rebreathers loaded onto the ageing chinese aircraft was challenging

The expedition team was treated to a MIG27 fighter taking off and landing...


Just to make sure that the trip has just as memorable end as the rest of the week the last morning finds us at the Sri Lankan air force base in Trincomalee at 05:30 in the morning. Rather than an 8 hour bus trip we have arranged for the air force to fly us back to Colombo. When we arrive there is no one there and the jungle at the edge of the airfield, the noise of the jungle and the monkeys in the trees add a sense of drama. As the sun rises over the jungle I feel like we are in a scene from the movie Apocalypse Now.

As the air force crew arrive and check us in we are entertained the sight of trainee pilots practicing touch and go landings. Our Chinese made air force plane is only just large enough to take us and our luggage and we have some interesting conversations trying to explain exactly what our rebreathers are.

An easy 40 minute flight and we arrive at Colombo airport. As we unload on the edge of the runway we are again entertained by a ringside seat for air force MIG 27 taking off and landing.

Check in and a commercial flight back to the UK was almost an anticlimax after that.

HMS Hermes is a stunning wreck and I can't wait to go back and dive it again as well as diving the other wrecks that were sunk in this historic encounter.

For anyone that wants to dive this fantastic wreck I'm going to arrange three weeks diving on it next year. The dates are:

  • 02 Jun - 10 Jun 2012
  • 09 Jun - 17 Jun 2012
  • 16 Jun - 24 Jun 2012

For more information on Mark Powell's trips to HMS Hermes in 2012, visit the Scuba Travel website or email Mark at mark@dive-tech.co.uk