Introduction
According to Dean @ Mevagh Diving, we are only the fourth team to dive the D6 submarine. The D6 also carries a few “firsts” which makes her a very special dive indeed:
- First (?) submarine-on-submarine sinking
- Only dive-able British submarine in Irish waters
- First British submarine with a deck gun
It is so rare for a submarine to sink another submarine. I’m not sure how many times it has happened, but this might be the first one.
It is a relatively deep wreck that I was fortunate to have the opportunity to dive and I had about 15-20 minutes on the wreck. The downline was placed perfectly at the stern and I swam the length to the bow and then went back before starting my ascent. My total dive time was about 2 hours.
I really wish I had thought about making a “2D” photogrammetry model (similar to the U-2511 which I will publish soon) before the dive. I think I could have got enough photos to do it even with limited bottom time. I got some good photos and the visibility was great but it was very dark on the wreck with very little ambient light.
D6 Submarine
Below are some historic pictures of the D6 submarine I was able to dig up.
Note that the “76” shown below on the conning tower is the “pennant number” which corresponded to the D6 submarine.
The HMS D6 was one of eight “D-class” submarines to be built. They were 164 feet long (relatively short compared to even WW II submarines) and had a beam of 20 feet. The standard complement was 25 sailors including crew and officers. They had 3 x 18-inch torpedo tubes with two in the bow and one in the stern with one reload per torpedo tube for a total load of six torpedoes.
The D6 was laid down in February 1910, launched in October 1911, and commissioned on 19 April 1912. She was also the first British submarine equipped with a deck gun.
Sinking
The D6 was assigned the duty to find, hunt down, and destroy the German submarine UB-73 which had been wreaking havoc in the area north of Ireland. The D6 was operating in concert with a decoy sailing vessel, the HMS Prize, in an attempt to lure in the UB-73. The problem was that the UB-73 was already there and waiting and watching.
The D6 was sank on 24 June 1918 when the UB-73 fired a torpedo which had a magnetic switch.
After some research, I found somebody who translated the logs of the UB-73 about the sinking of the D6:
I found another website which describes how the D6 likely sank:
“After the war, the British determined that D 6 was probably sunk by a torpedo employing a magnetic pistol. UB 73 fired a torpedo from a range of just 80 metres and her shot passed under D6 and exploded with an effect that seemed extremely mild, throwing a column of water 30-40 feet into the air. D6 showed no signs of damage for 20-30 seconds after the explosion, but suddenly pitched nose down and was lost. It was thought that a tank had been ruptured, leading to the failure of a battery tank a short moment later.”
Dreadnought Project Website
Of the crew of 26, only two sailors survived (Lieutenant Samuel Arthur Brooks and Sub-Lieutenant Frederick Secker Bell) and both were taken prisoner aboard the UB-73.
Diving the Wreck
The D6 lies 36 miles offshore so it took us about 4 hours on just the outbound transit.
It sits in brilliant white sand; however, we dove her on a very overcast and dark day so we didn’t get a chance to use that backdrop as efficiently as I would have liked. The wreck is relatively deep (90-ish meters) so bottom time is a bit limited without incurring a long decompression obligation.
However, the sub is relatively intact, lays on her starboard side, isn’t too big, and can easily be swam from one end to the other and then back.
Another dive team had been on the wreck a day or two earlier and, based on their photos, had an amazing window of time when the sun was out and the natural light was brilliant. That was not the situation for us but it was still one of the highlights of my dives in Malin Head. I love to dive submarines and this one was no exception.
It was a long day given the transit times and we didn’t get back to shore until late at night, but it was definitely worth it.
Photos
In general, given how overcast the skies were, the depth of the wreck and the lack of natural light, I had to boost ISO quite a bit on my natural light photos.
Upon descent, this was my first real picture of the submarine. The white sand around the sub is amazing and really provides a contrast to the wreck. You can also see the downline just to the left of the photo and placed perfectly. I had some delays getting in the water so Ben had already transited the wreck and was coming back at me and those are the lights in the distance. Note that exposure and ISO are boosted a TON in this photo.
The second photo shows the divers by the conning tower. I’m pretty sure Dean had mentioned that it is made of copper which is quite crazy. I couldn’t find any online references to that, but I’m assuming it is true.
The D6 design was one of the first to employ a “saddle tank” to help with ballast. I’m pretty sure that the opening area to the left in this photo is the saddle tank.
There is a large net at the bow that sticks up into the water column.
Below are a couple more photos of the conning tower which has fallen over to the side.
And the last photo shows Travis approaching the stern before we started our ascent.
References
