SC 209 served in the USS Patterson Group, on the Atlantic coast of the U.S. On 27 August 1918, this chaser was mistaken for a submarine, shelled and sunk by the freighter Felix Taussig.

Submarine Chaser SC 209

Photograph of submarine chaser SC 209. National Archives, RG-165WW. Thanks to Dan Treadwell for submitting the image scan.