Alcedo, a 981 gross ton steam yacht built in 1895 at Glasgow, Scotland, was purchased by the U.S. Navy in June 1917 and placed in commission as USS Alcedo (SP-166) late in July. She crossed the Atlantic the next month to join the patrol forces fighting enemy U-boats in the waters off western Europe. In the early hours of 5 November 1917, while she was escorting a convoy en route to Brest, France, Alcedo was torpedoed and sunk by the German submarine UC-71. Twenty-one of her crew were lost with their ship.

USS Coronet (SP-194), 1917-1919. Originally the civilian motor boat Coronet (1905)

USS Coronet, a 90-foot section patrol boat, was built at Morris Heights, New York, in 1905 as the motor pleasure boat of the same name. Acquired by the Navy in July 1917 and placed in commission in September of that year, she spent the rest of World War I assigned to the Third Naval District. USS Coronet was stricken from the Navy Register and sold in August 1919.