Lost WWII Dutch Submarine Found Off Australian Coast After 8 Decades

A Dutch submarine from World War II, HNLMS K XI, has been discovered off the coast of Fremantle, Australia, decades after its location was lost.

The submarine was believed to have scuttled at the Rottnest Ships Graveyard, but recent findings show it rests about 15 kilometers away in shallower waters.

A team of divers from WreckSploration found the wreck on January 1, 2025, while conducting a survey using magnetic data provided by the Maritime Discovery Group.

The submarine was later confirmed as HNLMS K XI with the help of the Western Australian Museum (WAM) and the Dutch Cultural Heritage Agency (RCE).

Historical records had indicated that the submarine was scuttled in deep waters within the graveyard, but it was actually located southeast of the site, at a depth of 40 meters instead of the recorded 80 meters.

The discovery solved a long-standing maritime mystery.

HNLMS K XI was built at the Fijenoord shipyard in Rotterdam for the Royal Netherlands Navy. It was launched on April 24, 1924 and commissioned on March 24, 1925.

The submarine departed for the Dutch East Indies (now Indonesia) on October 15, 1925, reaching Sabang on December 28, 1925.

During WWII, the submarine was stationed in Surabaya, patrolling the Dutch East Indies and the Gulf of Siam (now Thailand). After the Japanese attack on Pearl Harbour in December 1941, control of the vessel was transferred to British forces.

The submarine continued to operate in the region, extending its patrols to the northern Indian Ocean, reaching as far as Bombay (now Mumbai), India.

Though HNLMS K XI did not engage in direct combat, it contributed to Australia’s war efforts, particularly in rescuing survivors of a major wartime naval tragedy.

On March 3, 1942, the Australian minesweeper HMAS Yarra was escorting a small convoy through the Sunda Strait, attempting to evade Japanese forces and reach Fremantle.

The next morning, a powerful Japanese fleet was spotted approaching.

Lieutenant Commander Robert Rankin, Yarra’s commanding officer, ordered the convoy to disperse while he turned towards the enemy, laying a smoke screen and preparing for battle.

However, the minesweeper and its convoy were overwhelmed and sunk within hours.

Video Credits: Wrecksploration/YouTube

Only 13 out of 151 crew members of the Yarra survived. They drifted in the open ocean for five days, surviving a small amount of water and a few biscuits.

On March 9, 1942, HNLMS K XI rescued them, making a crucial contribution to Australia’s war history.

The submarine’s service ended on March 22, 1945, when it arrived in Fremantle after departing Colombo, Sri Lanka on February 20.

It was decommissioned the next month and handed over to the Australian Disposal Committee.

When docked at North Quay, an open valve caused it to sink. The submarine was salvaged six weeks later and in September 1946, towed out of Fremantle for disposal.

The Rottnest Ships Graveyard, which contains around 50 wrecks, has been under investigation by WAM for decades.

The graveyard is known to hold various military remnants, including six two-man Welman submarines, eight submersible canoes, four aircraft, and other discarded wartime equipment.

During World War II, Fremantle was the largest submarine base in the Southern Hemisphere and the second most important Allied submarine base in the Pacific, after Pearl Harbour.

Eleven Dutch submarines, including HNLMS K XI, operated from there during the war.

The wreck is now protected under Australian heritage laws, preventing any disturbance or removal of artefacts. Divers can visit the site, but all remains must be preserved as historical research.

Archaeologists believe this discovery provides valuable insights into post-war ship disposal practices near Fremantle. The use of archival data and advanced technology such as photogrammetry played a key role in identifying the wreck.

Reference: wrecksploration

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