The experimental submarine, M1, sank during mysterious circumstances on November 25th, 1925. Over one hundred sailors followed her to her grave. In 1999 Ocean Discovery divers filmed and investigated the wreck for the BBC. The network produced a highly acclaimed documentary “Journeys to the bottom of the sea” based on the video documentation and finds of the expedition.
M1 the experimantal submarine

The British naval forces have a firm place in history as one of the worlds most powerful navies. England used its navy to secure their vast empire and trading routs. In the early 1900 the first world war hit the world and the free world put much of their trust in the Royal Navy. The Royal Navy proved trustworthy and beat the German High Sea Fleet at the battle of Jutland. After the war the Royal Navy continued to improve its vessels including its submarines. The Royal Navy submarines had proved to be inferior compared to the German. This called for some experiments that in some cases, like the M-class submarines, prove to be quite prone to disaster.

Historical data

As a result of a discussion between the British Admiralty and the first sea lord John Fisher supported by the chief of the submarine division commander Hall experiments would begin mounting huge canons on submarines. The motivation was that a sub could take on much more 400 kg shells than torpedoes. " A sub with a 30 cm canon would once and for all end the war" Work began with construction of four experimental submarines, the M1, M2, M3 and the M4. The M4 was later to be excluded.The M1 and M3 was outfitted with a 12 inch canon taken from the scuttled battleship HMS Formidable. The M2 had her canon replaced with a seaplane hangar. The M2 sank with all hands in 1932 when her crew opened the hangar door

prematurely enabling water to enter her pressure hull.Finally, the 9 of July 1917, the M1 was ready to commence sea trial.. After extensive sea trials she was commissioned for service at the naval base at Portsmouth.

Disaster at sea

1925-November the 12th, Thursday, time 0805

The M1 had been in service for six years when she , under an exercise, tragically disappeared. The exercise took place out side Devon and included the mine sweepers HMS Burslem, HMS Newark, HMS Sherborne and HMS Truto acting as battleships steaming through the English channel. The convoy was protected by five submarines, the L17, L22 and the L23. The M1 and the M3 guarded the portside of the convoy. The M1 was commanded by captain Alec M. Carrie.

The sea condition was rough with limited visibility and high waves. The convoy sighted several commercial ships passing close by the area of the exercise. The submarines was ordered to dive immediately after executing a fire drill.

At 0805 the exercise was aborted and the submarine was back into surface position. The M1 did not respond and was no were to be seen. A huge rescue effort was executed but with no luck. The M1 was lost with all hands and with no explanation to the cause of the tragedy.

A Swedish ship responsible for the sinking of the M1?
The Royal Navy could not find any trace of the lost submarine and was therefore not able to examine the cause of the disaster. Many theories were tossed around and it was a hard time for the relatives who did not get any information from the admiralty.

Nothing happened regarding the investigation until a Swedish captain through the Swedish embassy, came with some very interesting observations.

The Swedish cargo ship Vidar had been one of the ships sighted by the convoy during the exercise. Vidars captain Anders Leonars Anell reported some unexplainable bumps that had struck his ship when they passed the convoy. This information finally gave the Royal Navy the answer to the mysterious disappearance. In the following trial it was ruled that nor Vidar nor her crew was responsible, the sinking of the M1 was nothing else than a tragic accident.

In the early spring, 1999, I was called up and asked if I wanted to work for the BBC shooting video on a submarine in the English Channel. A local diver, Innes MacCartney had discovered an unknown submarine outside the town of Portsmouth in southern England. The researchers from the BBC thought that the sub could be the long missing M1. The news about the possibility that the M1 could have been discovered made headlines over the UK. The BBC decided that they wanted to investigate further and make a documentary film.

The depth in the promising area was way to deep for us to work on under the HSE regulations. Underwater work under the regulations is restricted to 50 meters and the breathing gas had to be air. Now we needed to work at depths down to 80 meters and there was no way that we were going to use air when we had trimix. Kevin Gurr, the diving manager, managed to get us a permission from the HSE to work the way we were used to and use helium based gases. Of course we needed a diving doctor and a recompression system on the diving vessel but apart from that we were all set to go.

A former navy vessel, owned by the Mojo Maritime, was used as a platform. It gave us plenty of space for everything we needed, compressors, chambers, Ribs you name it. We also hade a side scan sonar and a ROV system on board to make the search for the submarine as effective as possible. .

Diving the M1

Diving the channel is at best pretty demanding. Mostly it's a pain due to shipping, current, tides, and bad visibility. We had a rough time the first two to three days with gale winds stalling us badly. Despite the horrible weather we managed to do some surveys that quickly gave result. From the sonar display we could clearly identify the shape of a submarine but not decide if it was the M1.

The weather finally settled and we prepared to go down and make a positive Id of the Submarine. On the ship we had several naval experts and historians that briefed us and gave hints of what to look for to help them identify the wreck and also to establish the cause of sinking. Obviously the first goal was to check out the big brass canon in front of the coning tower.

Ingemar, I and Kev went screaming down the decent line eager to get a first look of the mystery sub. The surface water was green and the visibility the first 20 meters was everything but ok, it was a green mess. At 30 meters all went black but the visibility improved a lot, I was pleased about that, its no fun trying to shoot video when you can't see. The current was stronger closer to the bottom and it was increasing in strength, we had missed the desired slack time.

I glanced down below me as I was dropping down towards the bottom. In the far distance, 20 meters away the contours of a submarine appeared. We swam closer and I could recognize the port hydroplanes, the rudder and the propeller. The excitement I felt was quickly turned into hesitation, the aft of the sub was all covered in monofilament fishing net, a divers worst nightmare. The only visual evidence of the net was dead fish that seemingly hanged free in the water. There was a real risk of getting pushed in to the net buy the current. The worst scenario was to drift backwards in to the net while concentrating on shooting video. We had a few close accidents during the week.

We shot video on the hydroplanes, their angle of attack is rather important to the experts trying to establish the last moments of the submarines faith. They were all 90 degrees vertical telling us that she tried to surface and reach safety. This must have been a horrible experience for the crew, trapped on the bottom of the ocean and with no hope of rescue.
We continued towards the stern section, a far from relaxing swim, fighting hard against the current and dodging monofilament net. On the way we swam over the aft anti aircraft gun. We saw plates missing on the

The BBC wants to do it deeper

hull but it seamed that the pressure hull was still intact. Suddenly the conning tower appeared right before my eyes. I had been concentrating shooting video of the pressure hull and when I turned around its ghostly shape appeared in the gloom. The tower was huge for a sub. We found the periscopes and masts still deployed, this proved that the submarine was submerged when she sunk. On one of the towers ladder the marine growth had fallen off and a bright glimpse of shiny brass reflected my video lights and caught my eye. Unbelievably beautiful, a brass tower but I'm pretty sure that was not the reason why the constructor chose to use this material.

We still had not found anything that positively identified the submarine as the M1 We were close though, all we had to do was swim past the tower and if we saw a huge gun everything would be rapped up. There was no gun in front of the tower…. But we could clearly se its foundation and the base that hold its tremendous weight in place. Ingemar signaled and I swam over, on the side of the hull a huge piece of rubble lying on the sand bottom. The gun was discovered.

We all felt pretty satisfied during our slow ascend towards the surface. We had identified the submarine and got some new information regarding the current state of the wreckage and also an idea of how the M1´s last moments must have been like. 69 officers and crew followed the M1 to its watery grave, leaving many in sorrow. I guess the worst thing for the relatives must have been to not know what actually happened.

During the week we made 12 more dives and despite technical problems with video cameras and the R.O.V we managed to get some very good video that definitely helped put some light on the circumstances around the sinking. This was the first technical diving project carried out according to the HSE regulations for deep offshore work in Europe. The situation changes when you are employed to do work as a diver, you then have to follow the stringent HSE regulations. This means decompression chamber, diving doctor and four pint mooring. This would not have been economically feasible with out the funding of the BBC.

A documentary about the project called Journeys to the bottom of the sea has been produced by the BBC.

The M1 is a war grave and protected by British and international laws. Our hope is that we might have helped the public to understand the reason why the M1 was lost and that relatives finally get at least some answers to their questions.

Technical information: The M1

Deplacement: 1600 ton
Length: 89.7 meter
Swath: 7.4 meter
Draught: 4.8 meter
Crew: 65 men
Officers: 4 men
Surface: Two Vickers diesel engines each giving 1200 bhp
Submerged: Two electrical engines each giving 800 bhp
Speed: Surface, 15.5 knots. Submerged, 8.5 knots
Max depth: 60 meter
Armament: One 30.5 cm Canon. Range 29 km
One 7.5 AA gun
Four 45 cm torpedo tubes. Eight torpedoes

*Archive picture supplied courtesy of the Barrow-in-Furness Submariners Association".

Text Ricahrd Lundgren