On 16 July 1914, the crew of "U-9" reloaded her torpedo tubes while submerged, the first time any submarine had succeeded in doing so. On 1 August 1914, "Kapitänleutnant" Otto Weddigen took command. On 22 September, while patrolling the Broad Fourteens, a region of the southern North Sea, "U-9" found a squadron of three obsolescent British "Cressy"-class armoured cruisers (, , and , sardonically nicknamed the "Live Bait Squadron"), which had been assigned to prevent German surface vessels from entering the eastern end of the English Channel. She fired four of her torpedoes, reloading while submerged, and sank all three in less than an hour. 1,459 British sailors died. It was one of the most notable submarine actions of all time. Members of the Admiralty who had considered submarines mere toys no longer expressed that opinion after this event.