A team of undersea investigators has located the wreck of USS Stewart, a US Navy destroyer that had been captured by Japanese forces shortly after the outbreak of World War II in the Pacific.
This discovery was made off the coast of northern California during a recent collaborative expedition between Ocean Infinity, the Air/Sea Heritage Foundation, SEARCH, the NOAA’s Office of National Marine Sanctuaries, and the Naval History and Heritage Command (NHHC).
The wreck of what was once known as “the ghost ship of the Pacific” was found within the boundaries of the Cordell Bank National Marine Sanctuary, and in an area consistent with historical accounts of its final disposal.
Stewart was repossessed by the United States following the Japanese surrender and was deliberately sunk on May 24, 1946, as part of a naval exercise.
Laid down in Philadelphia, Pennsylvania in September 1919 and commissioned in September 1920, Stewart was completed too late to see action in World War I but found itself on the front lines at the start of World War II.
In 1941, Stewart was stationed in the Philippines as part of the US Navy’s Asiatic Fleet, an understrength collection of old, largely obsolete warships tasked with opposing Imperial Japan’s onslaught after its devastating attack on Pearl Harbor.
Stewart was damaged during combat in February 1942, and a freak accident trapped it in a repair drydock on Java where its crew was forced to abandon it as enemy forces prepared to seize the island. Raised and repaired a year later, the destroyer was pressed into service with the Imperial Japanese Navy as Dai-102-Gō shōkaitei ("Patrol Boat No 102").
It was not until Stewart was found afloat in Kure, Japan at the end of the war that the mystery of the Pacific ghost ship was finally solved. The battered veteran vessel was recommissioned back into the US Navy in what was called an “emotional ceremony” and towed home to San Francisco.
Stewart served its country one last time as a target ship, absorbing fire from aerial rockets, machine guns, and naval guns for more than two hours before sinking.
More than 78 years would pass before the wreck was finally found.
On August 1, 2024, three autonomous underwater vehicles (AUVs) were deployed by Ocean to search for the wreck of Stewart.
These unmanned submersibles, each equipped with high-resolution synthetic aperture sonar (HiSAS) and multibeam echosounder systems, were programmed to simultaneously conduct an extensive and methodical scan of the seafloor that lasted 24 hours. This approach facilitated rapid coverage of a large search area, and when the data were retrieved, these revealed the unmistakable image of a sunken ship 3,500 feet (1,100 metres) below the surface.
Preliminary sonar scans revealed that the destroyer is largely intact and that its hull rests nearly upright on the seafloor. This level of preservation is exceptional for a vessel of its age and makes it potentially one of the best-preserved examples of a US Navy “four-stacker” destroyer known to exist.
Following the initial discovery, the team conducted an additional high-resolution sonar survey, then launched a detailed visual inspection of the site using a camera-equipped remote-operated vehicle (ROV). The video feed was transmitted live from the sea floor using a virtual satellite link to experts and various stakeholders on shore.
Additionally, the data collected by Ocean Infinity during the survey will be provided to NOAA’s Cordell Bank National Marine Sanctuary to support future environmental assessments. The high-resolution sonar, oceanographic data, and video imagery will offer vital information for habitat characterisation, helping NOAA’s scientists monitor and assess marine life in this sensitive area, as well as its ongoing ecological changes.