The U-boat that laid the mine that the USS Minnesota struck was the U-117 and was a Type UE 2. She was laid down on 27 May 1916 at the Vulcan, Hamburg yards. She was launched on 10 December 1917 and commissioned on 29 March 1918. She only had one commander during her one wartime patrol his name was Otto Dröscher. She did however have successes of 24 ships sunk for a total of 46,898 tons of shipping sent to the depths. U-117 was a mine-laying German submarine and was one of the most successful U-boats to operate along the United States East Coast during World War I. Her more notable kills include such popular northeast wrecks such as the Sommerstadt (by torpedo - also known as the "Virginia Wreck"), the Chaparra (by mine), and the San Saba (by mine), the shelling of the 5-masted schooner Dorothy Barrett, and the near sinking of the US Battleship USS Minnesota (by mine).
The wartime fate of the U-117 ended on 21 November 1918 where she surrendered to the United States Navy. During the post war years she was used for exhibitions along the United States Atlantic coast. The final chapter in the life of the U-117 came on 21 June 1921. Under the direction of Brig. Gen. Billy Mitchell, the Assistant Chief of the Air Service of the United States Army, the U-117 was sent to the bottom by 12 bombs from U.S. Navy Curtiss F-5Ls in 230 feet of water off the Virginia Capes (approximately 70 miles northeast of Virginia Beach). She still rests there today, with another of her sister U-boats the U-111, covered in fishing nets and almost completely intact in 235 feet of seawater and is a popular dive site with tourists. She still has live ordnance on her as several live torpedoes can be seen lying in the sand. It was common practice for WWI U-boats to carry extra torpedoes secured to the outer hull. This practice died out due to the obvious safety concerns from exploding torpedoes.
The above photo was shared with me by Joe Mikecin and is of the U-117's sail taken by his uncle, William T. Buda, GM1/C. His uncle saw the U-117 and took this photo of her while she was on Victory Loan Tours. You can see a "Victory Loan Team" poster hanging in the upper right side of the photo. Above the five U.S. sailors on the left side, can be seen a round life saver marked "U-117 Ex-German Submarine".
This view of the U-117 was provided by Bruce Jarvis. This photo was printed on American postcard stock, taken post-war during her victory loan tours. Of note is the battleship in the far right side, behind the U-117 is one of the two Delaware class battleships, the USS Delaware or the USS North Dakota.
Closer view of the above photo.
The 5-masted DOROTHY BARRETT, launched in 1903, was one of series of wood superschooners built in Bath, Maine by Gardiner Deering. She measured 250 feet in length and her gross tonnage was 2088. Designed for the coal trade, this bulk hauler made huge profits for her owners during World War I, when shipping rates went through the roof. Her captain during those years was William Merritt of South Portland, Maine. The BARRETT entered the South American trade and, in 1916, made a speedy run from Buenos Aires to Boston in 54 days.
After the United States entered the Great War, it became risky for U.S. sailing vessels to engage in long-range trade, but the BARRETT carried war-risk insurance in addition to her usual liability coverage. On August 13, 1918, en route from Santos, Brazil, she was waylaid off Anglesea, NJ, by the U-117, a late-model German submarine that had been preying on coastwise shipping along the eastern U.S. coast. She received one warning shot from the U-boat. Everyone aboard understood the signal and took to the BARRETT's yawl boat. The schooner was then set afire, presumably by an incendiary round from the U-117's 5.9-inch deck gun, and she sank in about 100 feet of water. A US Navy patrol boat arrived on the scene before the BARRETT went down but was unable to track the elusive U-117. Capt. Merritt and his crew, which included his two sons as mates, landed at Cape May, NJ without hardship. Merritt was later captain of Deering's big 5-master, CARROLL A. DEERING, launched in 1919. Under a subsequent skipper, the DEERING was found aground on Diamond Shoal, NC, in January 1921, with sails set but with no crew aboard. The mystery of the DEERING's grounding and the crew's disappearance has never been solved.