UB109

Canterbury Divers have recently adopted the wreck of the UB109 under the NAS 'adopt a wreck' scheme and will be undertaking detailed surveys of her over the next few seasons.

Diving the UB109
UB III class U-Boat

Class

UBIII

Constructed

Blohm &Voss-Hamburg

Launched

Hamburg 1917

Commissioned

31st December 1917

Length

55.3m

Captain

Kurt Ramien

Crew

34 or 36

Date Sunk

29th August 1918

How sunk

Remote mine

Crew Lost

28

Sectional drawing of UBIII class boat

She operated across the North Sea, English Channel and off the Spanish coast with the Flanders Flotilla destroying 5 ships, the last of which off the Azores ten days before she herself was sunk. Early on the morning of the 29th August 1918 the submarine was making her way past Folkestone when she was detected by the Folkestone Gate hydrophone Listening Station at 3.05am. The operator remotely detonated the line of mines as she crossed them and she was sunk. UB109 was commanded by Kapitanleutnant Ramien, who having sunk nearly 100.000 tons of shipping was rated by the German High Command as one of its aces. Only Ramien, his navigator and 6 men reached the surface.

Before the morning was over the Royal Navy had buoyed the craft and Commander Damants RN Divers were inside the wreck within 2 hours retrieving charts and code books.

Commander Damant's report of the 1918 diving on UB109:

She is lying in 14 fathoms on a sandy bottom, heading NE, 30 degree list to starboard. Fore hatch and conning tower open, no buoyancy remaining, about 20 ft abaft conning tower the damage begins and from there aft the vessel is shapeless wreckage. The damage is far more severe than that generally met with in deep minefield cases. 'The forepart of the boat is quite intact, for instance the large mirror on door of captain's wardrobe is not even cracked.
For this reason and because the depth was moderate I decided to work aft from the fore hatch without cutting any plates by explosives.
Owing to muddy water. it is generally quite dark on the highest parts of the wreck. While inside it is of course always so, and all work must be done by touch and hand lamp.

To get to their objective, divers had to negotiate a chain of five narrow apertures:

1)   fore hatch
2)   watertight door in fore bulkhead of officers quarters
3)   partition between officers and captain's quarters
4)   watertight door in fore pressure bulkhead of control room
5)   door of watertight cabinet.

      Between 4 and 5 are awkward obstacles formed by the compass and steering pedestals
      in the control room.

Afternoon on day of sinking, fore hatch was cleared of bodies, bedding, etc. and some personal material sent to the Admiralty.
On 30th and 31st much important material was recovered, although weather allowed work only on one tide. Divers had by now got as far as the control room.
On 1st September, again only one tide could be worked, but the control room was passed, the watertight cabinet entered and much valuable material found.
On 2nd and 3rd September, weather remained unfit, but on 4th September a whole day's work was got in, completing first part of the programme.
I do not propose sending men inside during spring tides, but there is work outside the hull that can be done then.

The inside divers, Leading Seaman E Blackford and Able Seaman T Clear, have shown much skill and determination in squeezing through these narrow places and making such a cool and thorough search.

The two divers brought up the sub's entire stock of charts, complete with new amendments, one of which marked her last cruise from the Channel to the Azores and back up the coasts of France and Spain and into the Straits where she was sunk.

Leading Seaman Ernie Blackford and Able Seaman Tom Clear held the record for reaching a sunken submarine.
They dived UB109 two hours after she was sunk. The water inside was quite hot, due to the seawater mixing with the sulphuric acid of her batteries.

UBIII class boat the UB88 UBIII class boat UB122

Current Condition

The Seabed generally at 25m, the bow has a bit of a scour under it and you can get 28m there, the deck is at 20m with the conning tower rising up to about 17m. The periscope rises above that to about 15m or so.

The stern is blown off and it is a short swim to its rear, both props have been salvaged. The pressure hull is intact, however, the tip of the bow has broken off and you have a large empty box like area open there. You can see 4 bow torpedo tubes just before that.

The hatches are open, where the crew bailed out and the Tin Openers (RN Divers) went in.