The captain of the F-1 submarine later testified that, in the fog, he didn’t see the oncoming vessel until the last second. Someone yelled to close the main deck hatch. But it was too late. The other boat rammed the F-1 and cut a huge gash in its side.

It was Dec. 17, 1917. Up in the conning tower, sailors heard the loud whoosh of air being forced out as their sub filled with seawater. The five men topside were thrown into the ocean and later rescued.

Below deck, 19 men were trapped. One man got to the surface, where he was spotted with searchlights. The F-1 sank in seconds a few miles off the coast of San Diego on a routine training mission.

Last month, the Woods Hole Oceanographic Institution unveiled what it says are the most sophisticated high-tech images of the Navy wreck taken since it was found some 50 years ago.

Ghostly videos showed the boat resting on its side in 1,400 feet of water - the deadly hole in its hull visible just behind the conning tower. The institution also released a photogrammetric representation of the sub assembled with about 5,000 video frames.

Video: Deep sea submersible from the Woods Hole Oceanographic Institution explores the crash site of USS F-1 submarine, which was accidentally rammed and sunk by another sub in 1917.(c) 2025 , The Washington Post

The images were captured during a dive to the wreck by the Navy’s “Alvin” deep submersible craft in February that was part of a testing program.

It revisited the century-old tragedy of a World War I submarine that entombed 18 sailors in a small, crowded boat that was only 15 feet wide but had once reportedly held the world record for the deepest dive by a submarine.

The F-1 is also believed to be the only U.S. submarine lost during the 1917-1918 U.S. involvement in World War I. No trace of the lost crew was seen during the dive.

“Given how quickly the sub sank coupled with how intact the wreck is, we believe that any such remains would be within the interior of the sub,” Bradley A. Krueger, an archaeologist with the Naval History and Heritage Command in Washington, said in an email.

The boat was state-of-the-art for its time; its record-setting dive was 283 feet in 1912. But after almost 108 years on the seafloor, it appeared slightly antique.

It’s “an early-model sub,” said the oceanographic institution’s Bruce Strickrott, a Navy veteran who was aboard the Alvin and piloted its descent from the support ship Atlantis on the surface. Krueger was also aboard the Alvin.

“It has almost a Jules Vernian component,” Strickrott said, referring to the 19th-century French novelist Jules Verne, who invented the fictional submarine Nautilus. “It actually had a wheel [in the open-air conning tower], like a traditional wheel right off a sailing ship.”

“You can see where the sub was half ship and half sub,” he said.

Once Alvin reached the bottom, “visibility was reasonably low, but as soon as we got close to the wreck, you could see it perfectly,” Strickrott said in a recent telephone interview.

Krueger said: “It was just this incredible moment where your heart kind of skips a beat. You’re seeing this incredibly well-preserved shipwreck just lying there quietly on the bottom of the sea.”

He said there was also a sense of solemnity, as they knew they were “essentially touring a grave.”

The collision occurred at about 7 p.m., when a heavy fog bank enveloped three U.S. submarines - the F-1; the F-3, which rammed into the F-1; and a third sub, the F-2 - as they were running on the surface in a loose formation off the California coast.

The boats were sounding their high-pitched “fog whistles” and had posted lookouts, according to a 1918 inquest. But the fog was so thick that one sailor testified that he could not see 50 feet ahead.

The Navy had only four F-class boats, and one - the F-4 - had already gone down with all hands two years earlier, when leaking battery acid ate into the hull.

The boats were only about 140 feet long. They had no radar, which was developed later, and crude, unreliable radios that could barely be heard over the engine noise.

Caught in the fog bank in the dark, all three boats began maneuvering to escape. The F-2 made it to safety.

But as the F-1 and F-3 scrambled in the murk, the F-3 made a U-turn that had it heading toward the F-1’s left side.

The two boats didn’t see each other till the last minute, according to the inquest.

The skipper of the F-3 shut down its engines in an attempt to stop. The F-1 swerved but couldn’t get out of the way. A two-foot-deep hole was punched in its hull.

The F-1 rolled to one side, righted itself and immediately began to sink, stern first. As the air was forced out of the conning tower hatch, it made a rushing noise almost like a whistle, witnesses testified.

The boat went down so fast that sailors said they “floated” off the deck. Those men, including the captain, Lt. Alfred E. Montgomery, were pulled out of the water by the crew of F-3.

“I did not make any effort to clear the ship,” said F-1 machinist J.M. Schmissrauter. “It seemed as though I just stepped right overboard.”

Sailor J.J. Burns testified: “I stood on the bridge until the water came up over my head.”

Several men on the F-3 sub said they saw an eerie blue flame come from the F-1’s conning tower as the boat went under.

“The men within the sub had no chance of escape,” said Krueger, of the Navy’s history command.

The collision knocked men aboard the F-3 down and sent dishware flying. But no one was seriously injured, and the damage was minimal.

The skipper, Lt. William M. Quigley, was on deck when he spotted an F-1 sailor in the water yelling for help.

“We made him out with the searchlights,” Quigley testified. “He was about seventy-five yards” away.

Quigley kicked off his boots and, with another sailor, went into the water to get him. But because of the fog and the rolling surface swell, they had trouble seeing him.