Lost WWI submarine captured in never-before-seen images off the California coast

Independent

23-05-2025

A World War I submarine wreck off the coast of Southern California has been captured for the first time in new video and images made possible using advanced deep-sea imaging technology.
The sunken U.S. Navy vessel now resting on the San Diego seafloor is known as the USS F-1. F-class submarines were based in the Pacific, serving at Hawaii and off California. The F-1 was lost at sea following an accidental collision on December 17, 1917, resulting in the death of 19 crew members. While others were rescued, the submarine sank in just 10 seconds. It was found again nearly 60 years later, according to the Submarine Force Library and Museum Association.
The high-definition images of the over a century-old submarine were taken in February and March, when researchers at the Massachusetts-based Woods Hole Oceanographic Institution used a human-occupied vehicle called 'Alvin' and the autonomous underwater vehicle named 'Sentry' to travel down 1,300 feet below the surface of the Pacific waters.
'Once we identified the wreck and determined it was safe to dive, we were able to capture never-before-seen perspectives of the sub,' WHOI's Bruce Strickrott, manager of the Alvin Group at WHOI and the sub's senior pilot, said in a statement. 'As a U.S. Navy veteran, it was a profound honor to visit the wreck of the F-1 with our ONR and NHHC colleagues aboard Alvin.'
The mission also included team members from the Navy, the Naval History and Heritage Command, and the National Science Foundation.
The National Science Foundation completed surveys of the submarine using video cameras, imaging systems on Alvin, as well as sonar systems on Sentry and the research vessel Atlantis. They also examined a Navy torpedo bomber training aircraft that crashed near the same location in 1950.
The sonar on Atlantic and Sentry was used to produce maps of the wreck and seafloor, while Alvin's cameras captured images of the wreck that was stitched into models capable of measuring the sub and the marine life it now supports. Researchers were also able to reconstruct the F-1 and create a three-dimensional model.
The dives were part of a previously planned training and engineering mission to give pilots-in-training time to hone their skills and to allow for the development of new technology.
'While these depths were well within the dive capability for Alvin and Sentry, they were technical dives requiring specialized expertise and equipment,' Anna Michel, the co-lead of the expedition, said. 'We were careful and methodical in surveying these historical sites so that we could share these stunning images, while also maintaining the reverence these sites deserve.'
Following the dives, they held a remembrance ceremony on Atlantic, ringing a bell for each of the service members lost at sea.
'History and archaeology are all about people and we felt it was important to read their names aloud," said Naval History and Heritage Command Underwater Archaeologist Brad Krueger. It was his first in-person dive on a historical wreck site. "The Navy has a solemn responsibility to ensure the legacies of its lost Sailors are remembered.'