HMS Venturer (P-68) was a Second World War British submarine that sunk two German U-boats and five merchant ships during her war service. Venturer was the lead ship of the British V-class submarine and the successor to the prior U-class of British subs. She was built at the Vickers Armstrong shipyard in Barrow-in-Furness UK. Her construction commenced in August 1942, she was launched eight months later in May 1943 and she was commissioned on 19 August 1943.
Upon completing sea trials and working-up, Venturer commenced operations patrolling the Norwegian coast searching for enemy surface craft and U-boats transiting between their bases and the sea. And, she was successful on several occasions, sinking three Axis vessels during 1944 alone.
Contrastingly, the German submarine U-864 was a Type IXD2 U-boat of Nazi Germany’s Kriegsmarine or “War Navy” that was the navy of Germany from 1935 to 1945 during World War II. The Type IX U-boats were designed in 1936 as a large ocean-going submarine capable of carrying cargo and intended for sustained operations far from home support facilities. They had been briefly deployed to patrol off the east coast of the United States to attempt to disrupt America’s continuous flow of troops and supplies bound for Europe. U-864 was commanded throughout its entire sea service by Korvettenkapitän Ralf-Reimar Wolfram and served with the 4th U-boat Flotilla undergoing crew training from her commissioning until 31 October 1944 when she was reassigned to the 33rd U-boat Flotilla a front-line unit of the Kriegsmarine, Germany’s Navy.
These two submarines converged onto a collision course to make history when late in 1944 U-864 was dispatched from Germany under the command of Wolfram to take part in Operation Caesar, a secret mission carried out by Germany during World War II to supply Germany’s faltering ally Japan with advanced technology in order to fuel their war machine. Ultimately, the operation ended in complete failure. The mission specified that the submarine transport advanced technology including Me-262 jet fighter parts and V-2 rocket guidance systems to Japan for use against American forces. The Messerschmitt Me 262, nicknamed Schwalbe (“Swallow”) in fighter versions, or Sturmvogel (“Storm Bird”) in fighter-bomber versions, was the world’s first operational jet-powered fighter aircraft. And the V-2, Aggregat 4 (A4), was the world’s first long-range guided ballistic missile and was powered by a liquid-propellant rocket engine. Also, on board U-864 was sixty-five tons of mercury which was necessary to produce bomb detonators. While in route and passing through the Kiel Canal, a sixty-one mile long freshwater canal in the German state of Schleswig-Holstein, U-864 grounded resulting in damage to its hull. So, to correct this issue, Wolfram sailed north to the U-boat pens at Bergen, Norway for repairs.
However, on January 12, 1945, while U-864 was still undergoing repairs, the pens were attacked by British bombers further delaying the submarine’s departure. Finally, with repairs completed, Wolfram sailed in early February. Concurrently, British code breakers at Bletchley Park, UK were alerted to U-864’s mission and its location utilizing decoded Enigma radio intercepts. Consequently, to prevent the German boat from completing its mission the British Admiralty diverted the fast attack submarine, HMS Venturer to search for U-864 in near Fedje, Norway. Commanded by rising star Lieutenant James Launders, HMS Venturer had recently sailed from its base at Lerwick the main port in the Shetland Islands, Scotland.
Coincidently, on February 6, U-864 passed nearby the Fedje area when complications began to arise with one of its main engines. Despite the repairs at Bergen the engine began to misfire resulting in increased noise being generated from the submarine making it more vulnerable to detection by enemy sonar. Radioing Bergen to inform them of the situation and that they would be returning to port, Wolfram was informed that a surface craft escort would rendezvous with them at Hellesoy Norway.
Simultaneously, Lander’s and Venturer were arriving in the Fedje area and he made a calculated decision to not utilize Venturer’s ASDIC advanced sonar active system in the search for the German submarine. Because, although the use of the ASDIC would valuable in locating U-864, it’s pinging sound might give away Venturer’s position. So, relying solely on passive, its hydrophone Venturer began listening and searching the waters around Fedje. Then, on February 9, Venturer’s hydrophone operator detected an unidentified acoustic that sounded like a diesel engine. After tracking the sound at a safe distance for a time Lander ordered Venturer to close on the contact and raise her periscope to allow him to take a peek. And, upon surveying the horizon Launders spotted another periscope and then proceeded to quickly lower Venturer’s and he correctly guessed that the other periscope belonged to his prey. He continued to slowly trail U-864 having plans to attack the German U-boat when it surfaced.
As Venturer continued stalk U-864 it became clear that she had been detected by Wolfram because the German submarine began to execute a typical evasive zigzag course. Subsequently, after pursuing Wolfram for three hours Venturer’s batteries began to run low and soon would require Launders to surface the boat to recharge them inciting him to act more quickly. So, anticipating U-864’s course, Launders and his men computed a three-dimensional target firing solution. And, although this type of calculation had been practiced prior, in theory, it had never been attempted at sea under actual combat conditions. With this work done, Launders began to maneuver Venturer in position for the kill only to be out-foxed by Wolfram several times. Until finally Wolfram erred giving Landers a brief window of opportunity, and so he fired all four of Venturer’s torpedoes at varying depths while slowly descending and with 17.5 seconds intervals between each. After launching the last torpedo he ordered Venturer to dive deep to deter any counterattack. Concurrently, upon detecting the torpedoes in the water Wolfram ordered U-864 to crash-dive and turn sharply to evade them. However, though U-864 successfully evaded the first three fish, it dived into the path of the fourth that struck the submarine broadside sinking it immediately with all seventy-three hands aboard.
For his actions off Fedje, Launders was awarded a bar to complement his previously awarded Distinguished Service Order. Upon the end of hostilities Venturer was marked for disposal however in 1946 she was sold to the Royal Norwegian Navy instead and was renamed Utstein. She served with the Norwegians until January 1964, when she was decommissioned, struck from the Royal Norwegian Navy register and scrapped.
The wreck of U-864 was discovered in March 2003 by the Royal Norwegian Navy located two miles west of the island of Fedje in the North Sea at a depth of 490 feet. The mercury she carried had been seeping out of rusted containers contaminating the region and killing sea life. Initially, it was recommended entombing the wreck under a layer of sand and gravel and sealed with concrete. However, the Norwegian government instead awarded a contract to a salvage company to raise the wreck, but, the proposed operation was put on hold pending additional environmental studies.
The underwater battle between HMS Venturer and U-864 is the only documented instance in the history of naval warfare where one submarine attacked and sank another while both were submerged in the same manner of an aircraft dogfight.