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The Woods Hole Oceanographic Institution (WHOI) and Naval History and Heritage Command (NHHC), aboard the Office of Naval Research (ONR)-owned research vessel (R/V) Atlantis, visited and documented the final resting places of two U.S. Navy sunken military craft off San Diego with the human-occupied vehicle (HOV) Alvin in late February 2025.
Alvin, carrying a science observer from both NHHC and ONR, was piloted by WHOI to explore the World War I-era submarine USS F-1 (SS 20), which serves as the final resting place for 19 Sailors, and a post-World War II Grumman TBM Avenger aircraft, BuNo. 53404.
The mission, funded by the U.S. National Science Foundation in partnership with WHOI’s National Deep Submergence Facility, had the main objectives to conduct Alvin and Atlantis team and pilot training in parallel with engineering exercises in collaboration with AUV Sentry. During this time, multiple systems were improved upon in Alvin, which are certified by Naval Sea Systems Command Advanced Undersea System (PMS 394), and support new pilot certification, conducted by the Navy’s Submarine Development Squadron Five for WHOI's National Deep Submergence Facility staff. However, the partnerships with NHHC and present-day submariners in the investigation of the two sites added a deeper purpose to the mission, further enhancing the training operation.
“Operating at sea has always been inherently dangerous, and even more so for early submarines. In this case, night, fog, speed, and radio miscommunications contributed to the loss of 19 men, who demonstrated great courage just by volunteering for submarine duty in those days,” said Naval History and Heritage Command Director Sam J. Cox, U.S. Navy rear admiral (retired).
The WHOI team first deployed the autonomous underwater vehicle Sentry to locate the wrecks, using side-scan and multi-beam sonar. Once located, a remotely operated observation vehicle descended to conduct a single reconnaissance dive on USS F-1 to assess the condition of the wreck. Next, the team equipped Alvin with an array of high-definition and 4K cameras to capture video and still imagery of the submarine and aircraft wrecks with the intention of creating three-dimensional photogrammetric models of the sites.
The team completed three separate dives, two on the Avenger and one on USS F-1, capturing hours of footage and imagery.
This was a unique opportunity for the NHHC Underwater Archaeology Branch. Although the Navy owns R/V Atlantis, it is certified by the U.S. Coast Guard, and HOV Alvin by Naval Sea Systems Command. The pilots of Alvin are qualified by Submarine Development Squadron Five, and while both vehicles are managed and operated by WHOI, this was the first time the Navy has made use of Alvin for the purposes of archaeological documentation.
"This is a remarkable success for the Navy, NHHC, and underwater archaeology," said Bradley Krueger, an archaeologist with NHHC's Underwater Archaeology Branch who participated in the documentation effort. "Using new methods and technologies to document the Navy's submerged cultural heritage, while also honoring its lost Sailors, is both an exciting and humbling experience, particularly as we approach the commemoration of 250 years since the founding of the U.S. Navy."
The wreck of USS F-1 is relatively intact, lying on its starboard side with many of its features still preserved and in their original configurations at a depth of more than 1,400 feet. Some elements, such as the fairing superstructure atop the pressure hull, have suffered more damage than other areas. Despite this, observers in Alvin stated that the wreck retains a great deal of physical integrity. One area of particular interest for observation included a large oval-shaped hole in the port side of USS F-1 just behind the conning tower, which led to the submarine's loss.
"The submarine's conning tower, periscopes, wheel, and hatches are all present, much as they were the same day the sub was lost," said Krueger.
“F-1 was the second submarine to be lost to an operational accident, the first being F-4 off Hawaii in 1915, which cost the lives of the entire crew of 21. Nevertheless, from such tragedies, hard lessons were learned that over time contributed to safer peacetime operations and more effective wartime operations,” said Cox.
Not far away, the wreck of the Avenger aircraft also quietly rests on the seafloor. The plane is upright and its wings are still spread as if it was flying; its fuselage and tail assembly are mostly intact. The engine and propeller are also still present, with each of the propeller blades bent toward the aircraft. Surprisingly, the cockpit glass is in place, with the cockpit canopy slid backward, indicating that the pilot escaped.
Of particular note is the presence of the aircraft’s national insignia, consisting of a white star and a horizontal white bar with a thin red stripe through the center.
"The degree of preservation seen on the Avenger is remarkable and many of its markings and symbols are still present and readable," said Krueger. "This key detail indicates the aircraft was lost in 1947 or later, which proved to be an incredibly helpful clue that led us to identify the wreck as BuNo. 53404," he continued.
For DSV Alvin Manager and Lead Submersible Pilot, Bruce Strickrott, one of the WHOI expedition leaders who conceived, planned, and executed the three total dives on the two sunken craft, it was much more personal as his Great Uncle was lost on board the USS Bullhead, a Balao Class submarine that was the last U.S. Navy vessel lost with all hands in World War II.
“For me, to dive to USS F-1 was one of my finest dives, and as a Navy veteran, it was an honor to dive with NHHC and ONR aboard Alvin; a fitting tribute to the F-1 crew,” said Strickrott. “We all recognized the solemn nature and importance of the dive in honoring the men who perished during this unfortunate accident in 1917 and see great value in these collaborations.”
“As a Navy veteran, making this dive – together with another Navy veteran and a Navy historian – was a solemn privilege,” said ONR Program Officer Rob Sparrock, who was in the HOV Alvin as it surveyed and analyzed USS F-1. “Lasting nearly eight hours, there was time to contemplate the risks that all mariners, past, present, and future, face. It also reminded me of the importance of these training dives, which leverage the knowledge from past dives, lessons learned, and sound engineering,” he continued.
Before the end of the voyage, the crew of R/V Atlantis, the WHOI team, representatives from NHHC, and the Office of Naval Research (ONR) participated in a small ceremony to honor the men lost aboard USS F-1. While gathered on the bow and situated over the final resting place of the submarine, the captain of R/V Atlantis read the names of the deceased as the boatswain tolled the ship's bell 19 times, one time for each Sailor lost. The somber occasion provided a respectful and reverent close to an otherwise successful mission.
On December 17, 1917, USS F-1 was participating in engineering competence runs with USS F-3 (SS 22) from San Pedro to San Diego. Upon entering heavy fog, the two submarines maneuvered in different directions, resulting in USS F-3 colliding with USS F-1 off Point Loma, California. Survivor testimony reveals that USS F-1 sank within seconds following the incident, taking with it 19 of the 24 crew members, while USS F-3 did not suffer serious damage.
After nearly 58 years, the Navy located USS F-1 in 1975, while searching for an aircraft that crashed in the area. Since then, few visits have been made to the submarine, with the recent WHOI expedition marking the first time archaeologists visited and assessed the site.
In October 1950, the Avenger suffered engine failure while off La Jolla, California, and successfully executed a water landing in calm seas. The pilot was able to exit the aircraft before it sank, so there was no associated loss of life. The intact nature of the wreck coincides with the historical record of loss, which further corroborates the identity of the aircraft.
Both USS F-1 and the Avenger are U.S. sunken military craft, under the jurisdiction of the Department of the Navy and managed by NHHC. In addition to their historical and archaeological importance, sunken military craft often serve as war and maritime graves, such as is the case for 19 Sailors of USS F-1.
NHHC will continue working with WHOI and partners to review the video and still images collected by DSV Alvin, complete the three-dimensional models, and complete site assessments for the two wrecks.
The expedition was made possible by the generous support of several stakeholders, including WHOI, ONR, NSF, Submarine Development Group, and Naval Sea Systems Command. NHHC acknowledges and appreciates these organizations' contributions for helping preserve, protect, and honor U.S. Navy history and heritage.
NHHC Underwater Archaeology Branch is responsible for locating, managing, researching, preserving and protecting the Department of the Navy’s nearly 3,000 shipwrecks and over 18,000 aircraft wrecks located world-wide, and which date from the American Revolution to the nuclear ages. Program staff hold maritime archaeological and conservation expertise and are equipped to conduct research on sunken military craft; manage a conservation and curation facility that stabilizes, analyzes, and houses a collection of artifacts recovered from sunken military craft; and engage in an expansive array of public outreach efforts, including partnering with the diving community.
To see a high-resolution imagery and video of USS F-1 or of the TBM Avenger from this expedition, please visit the WHOI site at https://www.whoi.edu/press-room/news-release/wwi-sub/.
For more information about USS F-1, visit https://www.history.navy.mil/research/histories/ship-histories/danfs/f/f-1.html.
To learn more about the TBM Avenger or obtain historical imagery, visit https://www.history.navy.mil/content/history/nhhc/search.html?q=TBM+Avenger
The Naval History and Heritage Command, located at the Washington Navy Yard, is responsible for the preservation, analysis, and dissemination of U.S. naval history and heritage. It provides the knowledge foundation for the Navy by maintaining historically relevant resources and products that reflect the Navy's unique and enduring contributions through our nation's history, and supports the fleet by assisting with and delivering professional research, analysis, and interpretive services. NHHC is composed of many activities, including the Navy Department Library, the Navy Operational Archives, the Navy art and artifact collections, underwater archeology, Navy histories, 10 museums, the USS Constitution repair facility and the historic ship Nautilus.
| Date Taken: | 05.22.2025 |
| Date Posted: | 05.22.2025 10:33 |
| Story ID: | 498692 |
| Location: | WASHINGTON NAVY YARD, DISTRICT OF COLUMBIA, US |
| Web Views: | 58 |
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This work, Deep-Sea Submarine Alvin Documents Remains of Two Navy Wrecks, by Clifford Davis, identified by DVIDS, must comply with the restrictions shown on https://www.dvidshub.net/about/copyright.
