At 1.45 AM U-9 finishes a busy night in the North Sea. U-9 finally catches up with SS Patria again and sinks her with one torpedo (19 lives lost). 4 survivors are picked up by the Swedish merchant SS Frigg.
U-55 sinks Norwegian SS Telnes off the Orkney Islands, Scotland (18 lives lost).
At 12.50 PM, Royal Navy destroyer HMS Grenville hits a mine, capsizes and sinks in the Thames estuary (77 lives lost). Two other destroyers brave the minefield to rescue 118 survivors.
At 9 PM, French steamer SS Quiberon is hit with one torpedo from U-59 and sinks with all hands lost, off Great Yarmouth, England.
At 10 PM U-44 begins stalking Greek steamer Ekatontarchos Dracoulis in the Bay of Biscay. Around midnight, U-44 fires a torpedo that detonates prematurely.
Royal Navy submarine HMS Sunfish fires 4 torpedoes at U-14 off Heligoland, Germany but all miss.