HMS Venturer (P68): The Only Submarine to Sink Another While Both Were Submerged

Built at Barrow

HMS Venturer was built by Vickers Armstrong at Barrow-in-Furness, launched in May 1943 and commissioned on 19 August 1943, a V-class submarine that spent much of her war patrolling the Norwegian coast, watching for U-boats and coastal traffic moving in and out of German-held bases.

A Solid Wartime Record

Beyond the engagement for which she is best remembered, Venturer sank three Axis vessels during 1944, including the German submarine U-771 on 11 November 1944 near the Lofoten Islands, and accounted for five merchant ships off the Norwegian coast during her operational career, a remarkably productive record even before her most famous action.

An Unrepeated Feat of Naval Warfare

On 9 February 1945, under her 25-year-old commanding officer Lieutenant Jimmy Launders, Venturer detected the German Type IX U-boat U-864 by hydrophone near Fedje Island off the Norwegian coast.

Launders tracked his target for some three hours while submerged, and facing depleted batteries, made the extraordinary decision to compute a firing solution entirely by hand, a technique that had never been attempted before because the calculations required to hit a three-dimensionally manoeuvring target were assumed to be practically impossible.

At 12:12, he fired all four bow torpedoes at staggered 17-second intervals and depths; U-864 evaded the first three, but unknowingly steered directly into the path of the fourth. The German boat exploded, split in two and sank with the loss of all 73 men aboard, some 31 nautical miles from Bergen.

The sinking remains, to this day, the only occasion in the history of naval warfare on which one submarine has sunk another while both were submerged, the only naval engagement ever fought entirely underwater.

Launders was awarded a bar to his DSO for the action, and his manually computed firing solution went on to establish techniques that influenced modern torpedo targeting systems. U-864 had been on a clandestine mission to Japan under Operation Caesar, carrying 65 tonnes of mercury and components for the Junkers Jumo 004 jet engine, adding a further layer of strategic significance to an already extraordinary action.

A Second Life in Norway

HMS Venturer was sold to the Royal Norwegian Navy in 1946 and renamed Utstein, serving under the Norwegian flag until January 1964, when she was struck from their register and subsequently scrapped, a fitting final posting for a submarine whose most famous action had taken place in Norwegian waters.