none 1 submarine sunk Result United States victory | Date 4 April 1918 Location Atlantic Ocean | |
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Similar Sinking of SS Kaiser Wilhelm d, Action of 10 March 1917, World War I, Action of 5 September 1918, Attack on Orleans | ||
The Action of 4 April 1918 was a naval action fought somewhere in the Atlantic Ocean during World War I. An unidentified Kaiserliche Marine U-boat attacked three armed transports of the United States Army and Navy, but failed to damage the American ships before she was sunk.
Action
On 4 April 1918, the armed transports Henry R. Mallory, Tenadores and Mercury were steaming back to the United States in convoy after having completed a troop transportation voyage to France. At 11:45 in the morning, a German U-boat of unknown designation surfaced and fired torpedoes at Mallory. Lookouts aboard the transport spotted the torpedoes, allowing the ship to successfully evade them.
The submarine was sighted by the other American transports; all three ships opened fire with their main guns, and appeared to hit the U-boat as she submerged. The vessels then maneuvered in close and depth charged the last-known location of the Germans. The three American vessels were credited with sinking the attacking submarine. The convoy reached the United States on or about 13 April 1918.