The sea was stormy on Sept. 26, 1918, as a convoy of merchant ships navigated the Bristol Channel in southern England. Escorting them was the Tampa, a 190-foot U.S. Coast Guard cutter with the mission of protecting the boats from German submarines.
The cutter separated from the convoy in the misty night to take on supplies and coal at a port. And then it disappeared. For more than a century, its fate has been an enduring naval mystery of World War I.
This week, British divers announced that the wreck of the Tampa had at last been found, nestled 320 feet deep in murky waters about 50 miles off the Cornish coast.
A torpedo from a German submarine killed all those aboard the cutter: 111 Coast Guardsmen, four U.S. Navy personnel and 15 British Navy personnel and civilians.
Adm. Kevin Lunday, commandant of the Coast Guard, said that the Tampa was the largest single American naval combat loss of life in World War I and that it had left “an enduring grief in our service.”
The discovery was the culmination of a three-year effort by the Gasperados Dive Team, a group of British explorers and researchers. They combed shipping logs and wartime messages, and collaborated with the Coast Guard to pinpoint the path and resting place of the vanished vessel.
Barbara Mortimer, a Gasperados researcher, collated scraps of information, sometimes single lines of text that by themselves offered little to go on. But once all the information was meticulously pieced together, she and her teammates narrowed the search to an area clustered with thousands of wrecks from warships, commercial ships and fishing vessels lost over centuries.
The timeline of the Tampa’s final moments slowly emerged.
“Urgent. Priority,” said a telegram dated Sept. 27, 1918, sent to the admiralty in London. “USS Tampa detached herself from convoy.”
The telegram provided the longitude and latitude of that last sighting. At 7 p.m., the ship was seen on the horizon, steering toward the port of Milford Haven, it said. At 8:45 p.m., a wireless operator “felt the shock of an underwater explosion,” the telegram said.
Then, in the hours that followed, Milford Haven reported that the Tampa was 12 hours overdue for its scheduled arrival.
The research team assembled a number of clues about where the Tampa ended up.
One telegram said a seaplane had spotted a “considerable wreckage” field of seven to eight square miles. Two bodies, in Tampa uniforms, eventually washed ashore and were buried in Wales, Ms. Mortimer said in an interview. She said the researchers also studied German U-boat records.
The Coast Guard provided historical records, technical data and archival images of the ship’s features so divers knew what to look for in the deep.
In April 2023, the team made its first two dives looking for the Tampa. Seven more followed, and an assortment of shipwrecks were spotted and examined.
On Sunday they zeroed in on an area where a British hydrographic survey had noted a “significant magnetic anomaly” suggesting the possible location of a steel wreck.
That information was checked against convoy records, Ms. Mortimer said. The team decided, “It’s worth a look,” she said. But she added, “I did not have high expectations.”
Dominic Robinson, one of the team’s divers, lowered himself into the cold, dark waters of the Celtic Sea in the late afternoon of April 26.
At about 311 feet down, he spotted wreckage, piled high. As he drifted slowly over the debris field, his light picked up objects from the chaotic jumble. Some stood out: There was a brass fire extinguisher, an anchor, shell casings and a high-pressure steam boiler that was used in the engines of ships like the Tampa.
Surveying the mound, Mr. Robinson said in an interview that he had a “gut feeling” that the ship had been blown apart, making the bow crumble and absorb the impact. “And the rest of the ship settled down behind it,” he said.
Then he drifted over some crockery. Another member of the team, Jacob MacKenzie, found a similar piece that was inscribed with the maker’s mark: “New Jersey.”
They had an “American connection,” Mr. Robinson said.
“That instantly connects me with the people on the ship,” he said in a video of the dive. “They would have eaten out of those bowls. All these people would have had parents, would have had nearest and dearest, and none of them knew where they are.”
The Coast Guard is gathering data from the Gasperados’ finds to confirm it as an officially designated war grave, said William H. Thiesen, the Coast Guard’s Atlantic area historian.
The Coast Guard has been contacting the families of each lost Tampa crew member over many years, awarding them a posthumous Purple Heart medal, Mr. Thiesen said.
“It provides closure to a chapter that has been open for 100 years,” he said.
Jeremy Davids, 48, of Florida said that a relative, Wesley James Nobles, died while serving aboard the Tampa at the age of 20.
“Drowned foreign waters sinking of Tampa 9-26-1918,” the official record of Mr. Nobles’ death says. Mr. Nobles had a rating of “boy,” an enlisted rank for younger crew members.
“It feels good knowing the fact that not only him but the other soldiers who lost their lives that day can finally rest in peace,” Mr. Davids said in an interview.
