The Dunmore East U-Boat trap

I was a youngster when I first heard the tale of UC-44, a German U-Boat that sunk when she struck her own mine and was salvaged and brought back to Dunmore East. There her design and fighting capabilities yielded invaluable information to tackling the U-Boat threat. It was only over Christmas that I came to realise the true back story to the affair, filled with intrigue, subterfuge and probably a lot of luck. For UC-44 was lured to Dunmore with the express purpose of being captured and the outcome played a role in an allied victory of the First World War.
In July of 1917 UC-42 deployed mines in Waterford harbour aimed at interrupting the flow of provisions out of Ireland to the allied side. Usually this meant that mine sweepers were deployed and the port access cleared. However, not this time. This time the admiralty or at least those in control of the western Atlantic approaches based at Queenstown (now Cobh) had other ideas.

Dunmore East lighthouse in the background as sub lay alongside the harbour
photo accessed from WHG and uploaded by Jim O’Mara in July 2013 
The losses being endured by the allies to U-Boats were steadily increasing. Resources were stretched, and the Admiralty seemed more content on maintaining a blockade of Germany than protecting those ships supplying the allies. Admiral Bayly and his team at Queenstown were fighting a losing battle despite the setting up of an anti-submarine division in December 1916, the introduction of Q ships, airships and the added resources gained when America joined the war in April 1917. American ships arrived at Cobh in May and were on patrol next day. The Navy needed all the help they could get and so the intelligence value of an intact sub was considered a priority.
So rather than clear the identified minefield to Waterford harbour a tactical decision was taken. The harbour was closed for two weeks, while a sham sweep by minesweepers was conducted. (This was in case spies were watching, or indeed U Boats). After two weeks the admiralty sent a coded signal to say Waterford was cleared and opened the harbour. Both sides had already cracked each other’s codes, and both sides seem to have been aware of such. (Nolan: pp232-4)
The German navy ordered UC-44, under the command of Kapitanleutnant Kurt Tebbenjoahnnes to sea on July 31st with orders to deploy 9 of her 18 mines in Waterford to replace those that had been “cleared” and the rest were designated for Cork harbour. She arrived off Dunmore on Saturday 4th August and surfaced at about midnight on a beautiful starlight night. The mines were laid while running underwater. While checking the boats position in the conning tower, to plot his course for Queenstown, he heard and felt a loud explosion and his boat lurched downwards. (McElwee pp 183- 189)
Tebbenjoahnnes found himself on the bottom of Waterford harbour with at least two other men, separated from the rest of the crew. Entombed and having failed to contact anyone in the main body of the submarine, they made the decision to try for the surface. Miraculously Tebbenjoahnnes was pulled from the water later that morning by three Dunmore East fishermen, Jack McGrath and two brothers Tom & Patsy Power, who had rowed out on hearing the explosion. Tebbenjoahnnes was cared for in the home of a Mrs Chester and was seen to by a Mr Austin Farrell. Later that morning he began his journey to London and life as a POW. (Ibid)
Meanwhile Admiral Bayly ordered a salvage operation to be commenced and it was initiated three days later under Lieutenant Commander Davis. Divers (tin openers) were deployed, and entered the sub to bring up the U Boats papers which were to prove explosive in themselves. It was decided to lift UC-44 to the surface and then to Dunmore. The strategy employed was basic, if complicated given that she was 90 feet down. Cables were dropped from a surface vessel, brought under the sub and then brought back to the surface. At low tide, the cables were secured to the decks of two ships and when the tide rose, so did the submarine. Once the sub was sufficiently off the bottom, the salvage vessels moved towards Dunmore. In all it took twenty lifts and as a consequence of bad weather it would be September 25th before they reached harbour. (McElwee pp189-191)
UC-44 lying at the quayside at Dunmore September 2017
accessed from:
The admiralty learned much about the design and capabilities of the submarine and they were keenly interested in the rescued mines and the deployment system. However it was the log books and other papers which arguably proved the most value. The log proved incontrovertibly what many had suspected but which was denied by senior naval personnel. It highlighted how easy it was for Tebbenjoahnnes and other U Boat commanders to avoid detection and slip through the existing protection around Britain. (Nolan: p235) Such information coupled with the with the rates of shipping losses highlighted that Britain and her allies were at risk of losing the war unless the U Boat menace was finally dealt with.
Macintyre (1965) explains the failure to grasp the U-boat menace “…submariners…comprised a breed apart” They suffered “…contemptuous refusal of senior officers and their contemporaries in surface warships to take them seriously.” This attitude created a “…mental inertia or lack of imagination of the great majority making for an obstinate conservatism” (Macintyre p 20). Some have claimed that the retrieval of UC-44 actually turned the war for the allies. What is probably true at least is that it helped in the continuing shift in attitudes in naval strategy and personnel, and arguably contributing to the removal of Admiral Jellico as commander of the navy, More ships and resources were provided to tackling the issue. The Dover barrage including 9,600 mines was completed and finally the convoy system was introduced. 
An enduring mystery of UC-44 was the notion that she was sunk by her own mine. There are many written accounts, both in books and online that suggest several scenarios. The majority believed for years that it was her own mine that sunk the ship. However, Nolan (2009) speculates that it may have been a casualty of the mines originally laid by UC-42, and as such a casualty of the trap created by the allies. More recently Stokes (2015) speculates that both UC-44 and UC-42, which struck her own mine in Cork Harbour later in 1917, were victims of sabotage, and that the deployment mechanism, or the mines themselves may have been tampered with by British agents operating in the German Naval dockyards. I’d imagine that we will never know for certain. 
My thanks to Michael Farrell of the Barony of Gaultier Historical Society for providing the names of the Power brothers of Dunmore mentioned above.  And to Ray Mcgrah for the name of his father also mentioned.
Macintyre. D. Fighting under the sea.  1965.  Evan Brothers Ltd. London.
McElwee. R. The last voyages of the Waterford steamers. date unknown. The Book Centre Waterford

McShane. M.  Neutral Shores.  Ireland and the battle of the Atlantic.  2012.  Mercier press.  Cork

Nolan et al.  Secret Victory.  Ireland and the War at Sea 1914-18.  2009.  Mercier press.  Cork
Stokes. R.  Between the tides; Shipwrecks of the Irish Coast.  2015. Amberly.  Gloucestershire.

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