Sunken World War I Submarine Located West of Point Loma

USS F-1 Submarine Sank in 1917 After Collision During Training Exercise, 19 Crew Members Lost

By Pia Gray / Futura / May 12, 2026

A research expedition off the coast of San Diego has captured the most detailed imagery ever recorded of the USS F-1 submarine. The World War I vessel sank in 1917 following a surface collision during a training exercise, taking 19 crew members down with it. Operating 1,300 feet below the surface, researchers used advanced deep submergence technology to document the site with precision, providing a clear window into a century old naval tragedy.
Locating the relic

The USS F-1 has occupied the seafloor west of Point Loma since its sudden sinking eight days before Christmas. While a Navy submersible initially spotted the rough location of the wreckage in 1972 during an unrelated search, a close-up survey remained impossible for decades due to the extreme depth. A joint expedition by the Woods Hole Oceanographic Institution and the US Navy finally resolved the mystery by deploying deep sea submersibles directly to the site.

Operating from the research vessel Atlantis, the team narrowed down the target site using historical Navy archives. The autonomous underwater vehicle Sentry scanned the seabed with multi-beam sonar, locating the sub on its first afternoon of deployment. Human occupied submersible Alvin then completed a series of seven dives to collect high-definition video and thousands of still photographs of the remains.

Preserving a war grave
Because the USS F-1 serves as the final resting place for 19 American sailors, the research team conducted an entirely non invasive survey. The sub maintains a heavy list on its starboard side with its bow pointed northwest, remarkably intact despite spending over a century in the deep ocean. The hull shows distinct structural damage from the historic impact, but the conning tower and external ship’s wheel remain clearly visible.

Engineers transformed the thousands of collected 2D images into a precise 3D photogrammetric model. This digital reconstruction allows underwater archaeologists to measure and monitor the degradation of the hull without physically touching the site. Following the final dive, the crew held a remembrance ceremony aboard the Atlantis, reading the names of the lost service members aloud and ringing a ship’s bell 19 times.

The 1917 collision
The disaster occurred during a 48 hour engineering and performance test between San Pedro and San Diego. The USS F-1 was maneuvering alongside sister submarines USS F-2 and USS F-3 when the group suddenly encountered a heavy patch of fog. The USS F-3 accidentally rammed the side of the USS F-1, tearing a massive opening into the hull forward of the engine room.

The damaged submarine filled with water and plunged to the ocean floor in less than ten seconds. The USS F-3 remained on the surface to pull survivors from the water, successfully rescuing five crew members from the ocean.

An unexpected secondary discovery
The sonar sweeps also investigated a separate military wreck just a short distance from the submarine. Researchers surveyed a World War II-era Grumman TBF Avenger torpedo bomber that crashed during a routine training flight in 1950. While WHOI pilots had previously encountered the aircraft during training dives, its exact coordinates had never been registered with the US Navy.

The recent data allowed the Naval History and Heritage Command to officially identify the plane and confirm that its entire crew survived the historical ditching. A clear stenciled number 13 remains visible on the plane’s engine nacelle, marking its assignment to a specific training squadron at the time of the accident.