Ghosts of Operation Drumbeat

By Jonathan L. Hoppe

The U-boat, under the command of Kapitänleutnant Hans-Dieter Heinicke, was part of Operation Drumbeat, a submarine offensive that the Kriegsmarine had launched against U.S. shipping along the East Coast in January 1942. The day before, U.S. Navy OS2U Kingfisher observation planes had caught U-576 on the surface, damaging her ballast tanks, and the boat was making her way back to St. Nazaire, France, when KS-520 was spotted.

Heinicke’s torpedoes found their marks, striking the cargo ships Bluefields and Chilore and the tanker Mowinckel, but it proved his undoing. The already damaged U-boat, unbalanced by the weight reduction from the loosing of the torpedoes, shot to the surface amid the convoy. Men on board the Chilore were close enough to see the boat’s hull number. While the Bluefields sank within four minutes, the crippled Chilore and Mowinckel made steam for Ocracoke Island. A U.S. Navy Armed Guard crew on board the motor merchant Unicoi opened fire on U-576, and two Kingfishers dove and dropped depth charges. Hemorrhaging fuel, the sub sank, taking her entire crew of 45 with her.

Both the Mowinckel and Chilore made good time for Ocracoke but unknowingly entered the Hatteras Defensive Mine Field. When the Mowinckel struck a mine and exploded, the crews assumed another U-boat had attacked. The Chilore also hit a mine. Both ships were abandoned, but their crews later made it to the Coast Guard Station on Ocracoke.

Nearly 70 years later, a submersible from GlobalSubDive, on a mission in partnership with the National Oceanic and Atmospheric Administration (NOAA), the Bureau of Ocean Energy Management (BOEM), SRI International, the UNC Coastal Studies Institute, and the nonprofit Project Baseline, glided over the ocean floor near the wrecks of the Bluefields and U-576, separated by 200 yards. As the sub trained its lights on the wreckage of the freighter, a large tear in her hull revealed her valuable ballast cargo: gleaming toilets, their surfaces as bright and white as when they were loaded onto the ship (marine life has yet to find a way to attach itself to porcelain glazing). The wrecks are a haven for countless fish, and hundreds of Bluefin tuna can be seen gathered over them. Local fishermen had known for some time that something very large was on the bottom attracting the fish.

An Island on the Front Line

For the people of Ocracoke, the sea had been bringing them life and death for centuries. In 1942 it brought war to their doorsteps. The horrors of the Battle of the Atlantic had begun arriving on 23 January, when the British tanker Empire Gem was torpedoed. Only two of her crewmen survived. “It was a terrible feeling,” said one rescuer, “especially when you see them jump overboard with flames on to ’em and know that they was goin’ into the fire just as quick as they hit. It really had a bad smell to it. It wasn’t all oil burning.”

Sometimes, the first sign that anything had happened was an explosion close enough to crack rainwater cisterns and rattle plaster off walls. Other times, the tides bore the ill news. That’s what happened with Bill Gaskell. In March a spar from the SS Caribsea bearing the ship’s nameplate washed up to his dock. He later learned that his son, a crewman on board the steam merchant, had gone down with the torpedoed ship.

The coming months brought more horrors. The bodies of four British officers from the Royal Navy Patrol Service’s Bedforshire, an armed trawler sent to help with antisubmarine duty, washed up on the beach; the vessel had been torpedoed. The remains, two identified and two unidentified, were buried with honors next to a small family cemetery on the island.

So many bodies arrived, one way or another, on the island that the Coast Guard Station’s old kitchen was converted into a morgue, and so many survivors of sinkings showed up that tar-paper shacks were built on the naval section base to house them.

Meanwhile, the ship sinkings continued. On 15 June, the tanker F. W. Abrams blundered into the Hatteras minefield, struck a mine, and went down. A month later when the crew of the Chilore was brought ashore, Ocracokers recognized a familiar face: Artis Bryant, a member of the island’s only black family who had left in 1916 to work dredges in Philadelphia. The war, by a quirk of fate, had returned him home. He and other rescued sailors savored their brief respite on the island before being reassigned to other ships to help sustain the war effort.

On 19 July, the tug Keshena, sent to remove the stranded and mine-damaged Mowinckel, herself struck a mine and sank. Her loss occurred at the end of Operation Drumbeat. By that time some 60 ships had been sunk off the North Carolina coast, earning the dangerous waters the nickname “Torpedo Junction.”

By October, the deadly Hatteras Defensive Mine Field had been supplanted by a secret magnetic indicator loop laid under the Ocracoke Inlet and a “Loop Shack” equipped with a battery of submarine-detection equipment and located among the island’s dunes. The war brought paved roads, electricity, and jobs to other parts of the island. Dozens of private boats were pressed into Coast Guard service as patrol vessels and other craft served as observation platforms under secret orders from the Navy.

A Race Against Time

A little digging reveals signs of how present-day Ocracoke was affected by the Battle of the Atlantic. The naval bases and gray-painted ships are long gone, but remnants of the Loop Shack remain, as do spent wartime shells, found while poking around the dunes.

Few tourists on board the ferry that plies the waters between Ocracoke and Cedar Island seemed aware that anything approaching the enormity of the Battle of the Atlantic had taken place so close by. The members of the Battle of the Atlantic Expedition 2016—the mission to explore the wrecks of the Bluefields, U-576, and others—hope that will change.

“A fisherman once told me that the fact that people outside coastal North Carolina don’t know the story is a testament to how effective the War Department’s campaign was in 1942 to keep it quiet,” related Dave Alberg, superintendent of the Monitor National Marine Sanctuary. “So here we have this amazing history, 1,600 men lost off the coast of North Carolina alone in one year, 1,100 . . . Merchant Mariners. We are in a narrow window of time to do something while the last of that generation is still alive, and we believe the opportunity to expand the Monitor boundary is an amazing opportunity to celebrate, preserve, protect, and promote that history.”

The sanctuary was founded in 1975 around the wreck of the U.S. ironclad Monitor, which foundered off Cape Hatteras in 1862. In February 2016 NOAA began soliciting public comment to expand the boundaries of the sanctuary. “To do that,” explained NOAA archaeologist Joe Hoyt, “we need to be able to demonstrate that we have the capacity to characterize these resources, [and] understand factors that are affecting them, that will allow us to develop meaningful management strategies moving forward.” Toward that end, the Battle of the Atlantic Expedition 2016 was undertaken to characterize and explore the wrecks of the Bluefields, U-576, and others. “That’s what it’s all about,” said Hoyt, “collecting enough data so that we can be the experts on these resources with the end goal of protecting them.”

One of the primary objectives of the expedition was to gather data to render extremely accurate three-dimensional models of the wrecks using a combination of high-resolution digital imagery and laser scanning. The laser scanners, made by 2G Robotics, originally were designed for the underwater inspection of structures such as pipelines and dams. NOAA first used the technology to model shipwrecks at Lake Huron’s Thunder Bay National Marine Sanctuary in 2015.

Laser scanning “worked so effectively in Thunder Bay and it was such a game-changing experience in how we document shipwrecks,” said Alberg, that it “immediately came up as one of the things we wanted to do.” He noted that the technology allows one to “take the shipwrecks virtually out of the water and share them with people who will never go 100 feet underwater.”

That mission to protect and share history found an ally in the Bureau of Ocean Energy Management. But neither NOAA nor BOEM operate manned submersibles able to reach the 700-foot depth of the Outer Banks wreck sites, so the agency partnered with Global Underwater Explorers, a U.S. nonprofit organization, to supply both the submersibles and the lead research ship, the Baseline Explorer, for the expedition.

Though the data from the expedition are still being processed, the scientists and expedition members are hopeful they will bring attention, recognition, and protection to the numerous wreck sites off the coast. “From our perspective,” said Alberg, “it’s visiting them the exact same way you’d visit Gettysburg or Shiloh. You go there, but you don’t go out there with a metal detector and you don’t go out there with a shovel.” Results of the expedition and further plans for the expansion of the Monitor Sanctuary will be shared later this year.


Homer Hickam Jr., Torpedo Junction: U-Boat War off America’s East Coast, 1942 (Annapolis, MD: Naval Institute Press, 1989).

Lorraine Huber, “Tales of the Sea: Storms, Doldrums,” Boca Raton News, 23 January 1978.

L. VanLoan Naisawald, In Some Foreign Field: Four British Graves and Submarine Warfare on the North Carolina Outer Banks (Raleigh, NC: Division of Archives and History, North Carolina Department of Cultural Resources, 1997).

Earl W. O’Neal Jr., Ocracoke Island: Its People, the U.S. Coast Guard and Navy Base During World War II (Ocracoke, NC: Earl W. O’Neal Jr., 2001).

Summary of Statements by Survivors of M/S “J. A. Mowinckel.” Panamanian Tanker, Navy Department Memo Op-16-8-5, 28 July 1942, RG 38, National Archives and Records Administration, College Park, MD.



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