"G9" was sunk by the destroyer HMS "Pasley" in foul weather on the night of 16 September 1917. "G9" had mistaken "Pasley" for a U-boat and fired two torpedoes at her. The first struck "Pasley" on her starboard quarter, but too acutely to detonate; the second passed astern. On seeing the submarine's wash, "Pasley"'s officer of the watch, Midshipman Frank Wallis, RNR, turned the boat hard to starboard and rammed "G9" just aft of amidships all but cutting her in two, and she sank less than one minute later with the loss of all but one of her crew, Stoker William Drake.