Diving - My Continuing Adventures underwater
More South Coast Wrecks
The M2 and James Fennel Wrecks
One of our club members, Saby, was very keen to dive the M2 Submarine. He'd asked me many times about diving it and a few months ago had contacted me to ask if I was interested in diving it with him on August 1st 2026.
It's a dive I'd done a few times before, but not in recent years, so I agreed.
Another club member, Bryn, also joined us and we had a relatively untroubled run down to Portland Marina, where we joined the dive boat, Scimitar for the dive.
A lovely day for the dive. Calm seas and blue skies
Most people on board had twinsets, except for a couple of rebreather divers and Saby and I, both on singles.
Diving as a 3, I knew Saby's air consumption, while not terrible, was likely to be the determining limitation on our dive.
As my single 15L cylinder wasn't O2 clean, I took along my 7 litre stage, to reduce my deco time, compared to air, as the others were both diving on 32% Nitrox.
As I kitted up, I realised that I'd never dived my stage with a single cylinder and didn't know how to attach it. I ended up with it connected across my stomach, seemingly easy to reach, but this lack of familiarity was to come back to bite me!
The M2 is a 'between the wars' submarine, originally built with a large pre-dreadnought Battleship gun ahead of the conning tower (along with a few other submarines), but converted to have a hangar from which a small seaplane could be launched to scout for targets, before returning to report and allowing the submarine to make an attack.
The M2 launching its plane in period.
Tragically, it sank while on exercise, just off Portland Bill with the loss of the crew. The theory being that were practising crash dive drills and the hangar door wasn't shut properly for some reason.
Saby, Bryn and I dropped in as a 3.
Saby's camera got entangled in the shotline, but I freed it, only to get entangled myself briefly.
That resolved, we descended on the submarine.
It was dark, but by the light of our torches, you could see the water was quite clear and we reckoned vis was 4-5M.
The shot was right by the catapult to launch the plane.
With the current running from bow to stern, we swam forward along the catapult and then dropped over the starboard side to look at the bow, which I didn't recall seeing on previous visits. The light was fairly good her, with green water visibly illuminating the bow, which was very sharp fronted.
During this time, we realised Saby wasn't with Bryn and I. but we continued the dive, assuming he was probably on the wreck still as he'd been there when we reached it.
We then turned around the front of the bow and headed alongside the port side of the hull around deck level, until we reached roughly where we'd come onto the wreck.
A diagram of the wreck
I could just make out the shape of the hangar ahead of me and we swam over to it, where I was surprised to see that it was possible to swim some way, at least, into the hangar. The last time I'd been here it had seemed to be more or less filled with sediment.
We entered and found that we could swim almost to the very back of the hangar where we turned around and swam along the opposite side wall.
On exiting the hangar, I turned up, leading Bryn to the conning tower's open bridge. You can imagine waterproof wearing officers scanning the horizon from here, looking for targets or the returning aircraft after a mission.
A video of the M2 dive
We swam around here a bit and rediscovered Saby (Bryn said he'd spotted him as we approached the hangar, as the only other diver with a single cylinder, but there were 3 boats on the wreck at the time, so that may have been someone from one of them), looking at the peiscopes before dropping down onto the rear decking and swimming along that.
Since my last visit it looked as if the deck level had been corroded more to reveal machinery (and lots of large congers and some crabs and lobsters) beneath.
After a few metres, we swam down the port side of the hull until we reached the curve of the lower line and beneath it a propelor shafter and mount, the prop being missing, presumably salvaged over the years, and behind that the rudder and the narrrow curved stern, which tapered to a vertically shallow edge.
I swam up and Saby indicated he had 80 bar, so we headed back along the deck as far as the conning tower for one last look around it (by now I had around 3 minutes of mandatory deco) and then headed forward slightly where I deployed my DSMB and we all started to ascend together. My reel jammed momentarily, but I was only pulled up 3 or 4 metres before it released and we continued up to around 20M, where my computer advised a switch to the 50% deco gas in my stage.
I made a mistake here. With my primary regulator in my mouth, I reached down and turned what I believed was the gas valve on my stage. That done, I dropped the reg from my mouth and picked up the stage's 2nd stage regulator. I tried to breath on it and nothing!
I put my hand down and turned 'the valve' again - Nothing. I then tried to retrieve my back gas 2nd stage, but couldn't locate it.
I was starting to get very low on air in my lungs and was fighting the urge to take a gulp, which would, of course, have been sea water!
I realised this was serious, but I managed to stay composed enough to look down and realised that I was turning, assuming it was the valve, was just a plastic cap on top of the first stage. Now I could see that, I reached for the actual valve, turned it and finally took a breath... To my great relief gas flowed into my lungs and I knew I was OK.
Looking ahead I could see the line to my DSMB dropping down below me slackly, meaning I'd risen without noticing it and a quick check showed I'd ascended 10M while this was going on.
I looked around and couldn't see the others either, but assumed they had stayed together (as it turned out, they hadn't, but were both back on the boat when I surfaced) and completed my 4 minute deco stop and the non-mandatory 3 minute safety stop, to be on the safe side, both at 6M.
It had been a great dive with what I'll admit was a scarey moment or two on the ascent.
Back on the boat, I explained what had happened to the others and we all agreed it had been a good dive, neither of them having had dived the M2 before.
A great article about the M2 with lots of excellent photos
We had a leisurely hour and a half surface interval, where we mainly ate our lunch and chatted.
Saby's drysuit zip had leaked seriously on the first dive, so he elected to skip the second.
The skipper offered us the options of the James Fennel, a small wreck to the west of Portland Bill, or a 'scallop dive' on the East Side.
While I like scallops, I'm not interested in collecting and cooking them myself, so I was pleased when the vote, narrowly, elected to dive the wreck.
Bryn and I dropped in, descended the shotline and found ourselves just the starboard side, and slightly ahead of, the fairly substantial cylinderical boiler.
We looked around that for a few moments and then I swam, into the slight current, behind it, to find the engine, complete with it's numerous pistons.
As I recall, there's not much aft of that remaining, so we swam to the port side, where there was some significant hull remaining and then explored some of the wreckage near the boiler.
Then we gave into the current and drifter forward, stopping to examine a few areas of the wreck, much broken up and flattened, before drifiting of it altogether.
A video from the second dive of the day
The skipper mentioned that, if we drifted with the current, we may find another wreck, which I had never seen on previous dives on the James Fennel.
For a while, all we saw were the huge, house-sized boulders that litter the seabed here, but then we saw something rising up that was clearly man made.
It was, I think, the broken bow of a ship, lodged into the rocks. We explored it a little and then came across a significant propellor shaft.
Thinking it may lead to more wreckage, we followed it, but it ended in a lump of iron, with no sign of any substantial wreckage, so we turned around and headed back to spend a few more minutes on the original site and then started to drift on, passing many more of the huge boulders, but the seabed started to drop away and we were both getting low on gas, so Bryn indicated we should ascend after about 35 minutes.
We completed our safety stop and returned to the boat.
A good second dive, far better, in my opinion, than a 'scallop dive'.
