Greek submarine Xifias (1911)

Xifias (Ξιφίας, "swordfish") was a Greek submarine (actually called a "submersible", καταδυόμενον, according to the then current French terminology) which served during World War I. It was the third submarine to enter service in the Greek navy, and the second and last vessel of the Delfin class. It was taken over by the French in 1916, and decommissioned in 1920 without seeing action.

History
Along with its sister ship Delfin, the Xifias was ordered in 1910 from the Toulon shipyards in France. It was delivered to the Royal Hellenic Navy in March 1913, shortly after the end of the First Balkan War. It was thus unable to participate in any naval operations against the Ottoman fleet. Like its sister ship, Xifias was plagued by mechanical problems and had insufficient operational capabilities; its use was minimal in the years that followed. Xifias and the rest of the Greek fleet were confiscated by the French in 1916, during the Greek National Schism. When the ships were returned in 1919, the two submarines were in a bad shape, and the following year, they were decommissioned.

Tradition
A second vessel of the Hellenic Navy has received the name Xifias: the British U class submarine HMS Untiring (P59), which was leased to Greece in 1945–1952.