WWI German U-boat found off US coast 100 years after it sank

The wreck of SM U-111 lies on the seafloor about 40 miles off the coast of Virginia, at a depth of about 120 feet. It was rediscovered in July after being deliberately sunk over 100 years ago.

The wreck of SM U-111 lies on the seafloor about 40 miles off the coast of Virginia, at a depth of about 120 ft. It was rediscovered in July after being intentionally sunk over 100 years in the past.
(Picture credit score: {Photograph} by Benjamin Lowy for Nationwide Geographic)

A crew of shipwreck hunters has found a unprecedented sunken vessel off the East Coast of america: the wreck of a World Conflict I German U-boat sunk by U.S. warplanes a century in the past for goal apply.

According to an exclusive report by National Geographic (opens in new tab), the crew confirmed the identification of the wreck in early September as that of SM U-111, a submarine that served within the Imperial German Navy. After Germany agreed to an armistice in 1918, the U-boat surrendered to the British, who saved a handful of the early submarines to the U.S. to review and reverse engineer. In 1922, the U.S. Navy intentionally sank the vessel, however its actual location was not disclosed.

However in early July, wreck researcher Erik Petkovic and his colleagues discovered the SM U-111 with a remotely-operated underwater car (ROV) at a depth of about 400 ft (120 meters) and about 40 miles (65 kilometers) off the coast of Virginia.

“We had been fortunate,” Petkovic advised Stay Science, describing the dwell video photographs despatched again to their analysis ship by way of the tether of the ROV. “We had been on the underside of the Atlantic Ocean, and we noticed the wreckage. We panned the digicam, and the conning tower was proper there.” (A conning tower is the raised platform above the highest deck of a submarine.)

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The SM U-111 was considered one of 5 German U-boats from World Conflict I that had been sunk in U.S. waters (there are additionally eight from World Conflict II) and it is the final to be rediscovered.

When the U-boat sank, the U.S. Navy thought the seawater on the location was a lot deeper, and that the vessel would fall to the seafloor about 1,600 ft (500 m) beneath the floor, Petkovic mentioned.

However data of the depths was imperfect 100 years in the past, and so SM U-111 got here to relaxation in comparatively shallow water subsequent to a deep abyss. “If it was one mile to the east, it was within the abyss and it by no means would have been seen once more,” Petkovic mentioned.

The discoverers revisited the site in September this year in a research vessel equipped with a remotely-operated underwater vehicle (ROV) to examine the rake with video cameras. — The discoverers revisited the location in September this 12 months in a analysis vessel geared up with a remotely-operated underwater car (ROV) to look at the rake with video cameras. (Picture credit score: {Photograph} by Benjamin Lowy for Nationwide Geographic)

Submarine menace

Germany constructed the SM U-111 within the northern port metropolis of Kiel in 1916 and it joined the battle at sea in early 1918. The submarine made three raids on industrial delivery vessels within the Irish Sea and the English Channel, and sank at the very least three Allied service provider ships.

“The primary U-boat battle from 1914 to 1918 usually will get missed,” Innes McCartney, a nautical archaeologist at Bangor College in the UK, advised Stay Science in an e-mail. “However it is very important acknowledge that compared to World Conflict II, the U-boats of the Kaiserliche Marine [Imperial German Navy] sunk twice the variety of ships and sustained solely 20 % of the losses.”

McCartney was not concerned within the rediscovery of the SM U-111, however he is discovered other World War I U-boat wrecks.

“Importantly for the Allies, had it not been for the expertise gained in 1917 and 1918 particularly, the marketing campaign in opposition to the U-boats in World Conflict II would have confirmed extra of a problem,” he mentioned.

After Germany agreed to the armistice in November 1918, the SM U-111 was surrendered to the British after which given to the U.S. Navy; and in April 1919 it set out for the U.S. with a crew of 32 U.S. sailors — 17 of whom had by no means been aboard a submarine earlier than, Petkovic mentioned.

To avoid wasting time, the commander selected the shortest — and most harmful — northern route throughout the Atlantic, which was strewn with icebergs and had claimed the R.M.S. Titanic seven years earlier than.

As well as, the submarine had solely German signage, so the U.S. crew did not know learn how to function the vessel’s gyro-compass, and needed to navigate with a magnetic compass; and a plug in an open valve manufactured from a “exhausting, gummy substance,” secretly put in by German saboteurs, dissolved within the seawater 4 nights into the voyage, flooding and nearly sinking the vessel.

“It is actually outstanding that they survived,” Petkovic mentioned.

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The open hatch on the conning tower of the U-boat reveals an interior ladder. The vessel was deliberately sunk by the U.S. Navy after being reverse-engineered and then used for target practice. — The open hatch on the conning tower of the U-boat reveals an inside ladder. The vessel was intentionally sunk by the U.S. Navy after being reverse-engineered after which used for goal apply. (Picture credit score: {Photograph} by Benjamin Lowy for Nationwide Geographic)

U-boat wreck

After its arrival on the U.S. East Coast, SM U-111 was used to advertise a remaining 1919 problem of battle bonds in Brooklyn, and was then examined in opposition to the most recent U.S. submarines. Ultimately its engines and tools had been stripped out, and in June 1921 U.S. warplanes utilizing it for goal apply sank the German sub.

However the vessel was thought-about a navigation hazard on the location the place it first sank; and so it was raised and towed into deeper water in August 1922, the place it was sunk for the final time by opening its hatches and setting off an explosive depth-charge close by. Its actual location was not publicly disclosed.

Petkovic had looked for the wreck of SM U-111 for a number of years, after noting that the opposite deliberate wrecks of U-boats in U.S. waters had been present in shallower waters than anticipated. He mentioned the important thing to the invention was figuring out which U.S. Navy ship had towed the disabled U-boat to its remaining vacation spot, after which gaining access to its logbook. They discovered the wreck of SM U-111 nearly precisely on the location described within the ship’s logbook. “It was proper on the cash, actually near the numbers that we had,” he mentioned.

Petkovic now hopes to dive to the wreck subsequent summer, though it is at an excessive depth even for technical divers with the most recent rebreather tools, which recycles the gases divers exhale and permits them to remain underwater longer.

“It is pushing the restrict by way of rebreather expertise and the bounds of human endurance,” he mentioned. “However there are guys on our crew which might be able to doing it… it is nonetheless a harmful dive, however that may be a aim of ours.”

You possibly can learn extra in regards to the German U boat discovery on National Geographic (opens in new tab).

Tom Metcalfe is a contract journalist and common Stay Science contributor who relies in London in the UK. Tom writes primarily about science, house, archaeology, the Earth and the oceans. He has additionally written for the BBC, NBC Information, Nationwide Geographic, Scientific American, Air & House, and plenty of others.