July the 30th the German U-Boat SM U-28 – drive by Freiherr Georg-Günther von Forstner – targeted the Iberian, a British cargo ship, 17 kilometers off the Fastnet lighthouse, Cork County, Ireland. The ship was sunk and seven members of the crew died. The day after, the U-28 sank two Royal Navy ship: the HMS Nugget and the HMS Turquoise, both offshore the Isles of Scilly, an archipelago of Cornwall.
To counter the naval blockade of the French and British fleets and provoke the greatest possible economic damage to the Entente, the German military authorities fielded a submarine fleet operating in the Atlantic Ocean. This caused serious damage to the Entente, but failed to achieve the proposed goals, nor to change the tide of war. In return, the German submarine fleet lost, during the war, more than half of its units.