wreckDiving

U-133: the boat's history

• Text: Nicholas Vasilatos
• Research: Nicholas Vasilatos

U-133 was a VIIC type German submarine which was mined off Aigina, Saronikos Gulf on 14 March 1942 and lost with all hands. Her rather well preserved wreck rests in 74 meters of water and provides a link to one of the most interesting chapters of modern naval warfare.

Type VIIC boats were the workhorses of the German submarine force, 660 boats of the type saw service (including the C/41 variant). From an operational point of view they were extremely flexible and were used in almost all the theatres of war. Of 769/871 tons displacement (surface/submerged) and with a length of 66.10 meters, VIIC boats had an operational range of 8500 nautical miles surfaced and cruising at 10 knots but just 80 miles submerged at a speed of 4 knots. She could manage about 17.50 knots surfaced but only 7.60 knots submerged, the differences being representative of the limited underwater capabilities in terms of speed and endurance of submarines of that era which could be viewed rather as submersibles, essentially surface crafts that would dive to escape and remain or attack undetected. Her operational depth was 100 meters and her crash depth is reported from 200 to 250 meters depending on the source. Newer studies estimate that in fact it could be as deep as 280 meters. Her propulsion plant consisted of two 6-cylinder supercharged MAN M6V40/46 2800 BHP diesels and 2 BBC GG UB720/8 560kW motors. The boats had an armament of four bow and one stern tube of 53.30cm with 14 torpedoes. On her foredeck she carried an 8.8 cm gun while on a platform to the aft of her conning tower they carried a 2.0 cm flak gun. Wartime complement was anywhere between 44 and 60 men1.

The boat had a short career, and was lost due to an accident rather than enemy action. U-133 was built in 'Bremer-Vulkan AG' owned 'Vegesacker Werft GmbH' yard at Vegesack, Bremen. Her keel was laid in August 1940, she was launched in April 1941 and was commissioned on 05 July 1941 joining the 7th Flotilla. Her first commander was Kapitänleutnant Hermann Hesse. On 22 October she left Kiel to operate in the North Atlantic. The patrol would prove fruitless for U-133 which put into her new base at Saint Nazaire on the 26th of November. On 16 December she sailed for transfering to the Mediterranean2. The boat arrived on 29 December 1941 at Messina wherefrom she left again for her third patrol off the coast of Egypt and Cyrenaica on the 1st of January 1942. On the 17th of January 1942 Hesse succesfully attacked the destroyer HMS ‘Gurkha’ which was escorting a convoy off the Egyptian coast. This would be the first and sole success of U-133. On the 22nd she arrived at Salamis naval base and joined the 23rd Flotilla. On the afternoon of the 14th of March 1942 she sailed from Salamis under the command of Oberleutnant zur See Eberhard Mohr. At about 19:00 hours she run into a mine and went down with all her crew of 45 hands. On the light of available evidence, U-133 entered the Tourlos - Phleves minefield probably due to a navigational error. The minefield was laid by the Greeks upon the declaration of war with Italy and was later amplified and used by the Germans.

U-133's wreck was later located and dived in order to evaluate the possibility of salving the boat. However, the salvage attempt never materialized due to the depth and the condition of the submarine. Quite a few years afterwards it was found again by fishermen and in 1997 Kostas Thoctarides was the first to systematically research her. As initially argued, submarine and submarine warfare development has been one of the most fascinating aspects of 20th century naval warfare. The wreck provides a link to this development and is therefore important both from an archaeological as well as from a historical perspective.

Notes:

• 1 Particulars may differ slightly according to source and relate to U-133's batch, i.e. boats Nos U-132 up to U-136. Different boats data will differ according both to builders and time built.
• 2 In summary we point out that during World War II the Mediterranean was considered an extremely dangerous theatre for submarines. It was a battlefield with restricted sea room and clear waters; submarines were exposed to air attack to a much greater degree than in the Atlantic. U-boats were generally unable to repeat their First World War successes in this area. From a strategic point of view many considered the deployment of submarines there a waste of resources, recourses much needed in the critical theatre of operations, the Atlantic and the convoy war.

Bibliography and Sources:

• - Bundesarchiv/Militärarchiv, Freiburg
• - Rossler, Eberhard (1975) The U-Boat. The Evolution and Technical History of German Submarines, Arms and Armour Press, London, Melbourne
• - U-Boot Archiv, Cuxhaven
• - Φωκάς, Δημήτριος Γ. (1953) Έκθεσις επί της Δράσεως του Ναυτικού κατά τον Πόλεμον 1940-1944, Τυπογραφείο Π.Ν.

U-133: the wreck today

• Text: George Kamarinos, Nicholas Vasilatos

The wreck rests on a flat sand bottom in 74 meters of water with a port list and her forepart pointing at a WNW direction. It is surrounded by a debris field. The bow has been cut off from the explosion and is now positioned at a right angle to the port of the stern, lying on her starboard side. Heavy marine growth has developed on the wreck which in places totally clutters the structure beneath it, like the 8.8cm gun (which is also covered in netting) and the flak platform to the aft of the conning tower. The wooden casing deck has disintegrated making the under deck fittings and piping of the boat readily observable. The conning tower manhole is open and the two periscopes lowered. The boat was navigating on the surface when she was lost. Her twin rudders are put to starboard suggesting that possibly a maneuver was made shortly before or immediately after she run into the mine. Conditions at the wreck are generally mild. Since in the confines of the Saronikos Gulf, visibility is medium, usually in the range of 10 meters. Current may vary from none to somewhat strong which can make swimming the wreck hard and the use of scooters desirable. The wreck falls into the T2 range therefore we are using Tmx 15/55 as bottom gas and EAN50 and Oxygen as deco gases. We usually spend 25 minutes down at the wreck which gives total dive times of about 100 minutes.

Although U-133’s remains had been dived and partially documented, there is much to be desired in terms of field research. A potential danger to the wreck lies in the fact that it is frequently visited by divers who disturb the site either unwillingly or not.

Team members:

• - Antonis Hatziantoniou: diver, surface support
• - George Kamarinos: diver, surface support
• - Anders Knudsen: diver, videography
• - Thanos Kopitsas: diver, videography, surface support
• - Sarantis Malafouris: diver, surface support
• - Achim Schloeffel: diver, photography
• - Helen Tsopouropoulou: diver, photography, surface support
• - Nicholas Vasilatos: diver, surface support