USS R-18 (SS-95)
 USS R-18 (SS-95) was an R-class coastal and harbor defense submarine of the United States Navy. Her keel was laid down on 16 June 1917 by the Union Iron Works in San Francisco California. She was launched on 8 January 1918 sponsored by Miss Marion S. Russell and commissioned on 11 September 1918 with Lieutenant Commander Felix X. Gygax in command.