TSS Athenia of the Donaldson line was a twin screw steamer (TSS) that was sailing across the Atlantic when the U-30, commanded by Fritz Lemp, mistaking it for an armed merchant cruiser (an ocean liner or merchant ship requisitioned for naval service and armed with a mixed armament) fired a torpedo that struck the Athenia in the stern, once Lemp got in for a closer look, he was mortified to see what he saw: an ocean liner, sinking, with passengers, that HE torpedoed. The Athenia sank about 14 hours later, taking 117 passengers and crew down with her.