On 15th October the Squadron was on patrol off the Aberdeenshire coast. The ships were in line abreast at intervals of 10 miles. HMS Hawke stopped at 9:30am to pick up mail from her sister ship Endymion. After recovering her small boat with the mail, HMS Hawke proceeded at 13 knots to regain her station.
German submarine U-9 had sunk three British cruisers on 22nd September - 1500 British seamen had perished with the torpedoing of the ‘Livebait Squadron’. On a straight course, HMS Hawke became victim number four.
At 10:30am the first torpedo from U-9 struck her above the engine room, igniting a magazine. On fire from fuel in the engine room and ripped apart by explosion, within minutes HMS Hawke capsized. The torpedoing was not witnessed, so the rescue of survivors was delayed.
Dispatched to search for HMS Hawke, the destroyer Swift located a raft carrying one officer and twenty-one men. A boat containing forty-nine survivors was found by a Norwegian steamer. 526 of HMS Hawke's officers and men died, including her Captain Hugh P.E.T. Williams. Most of the bodies were not recovered. In total only four officers and seventy crew were saved.