During World War I, "79 T" was used for convoy, patrol, escort and minesweeping tasks, anti-submarine operations, and shore bombardment missions. On 24 May 1915, "79 T" and seven other 250t-class boats participated in the Bombardment of Ancona, which involved shelling of various Italian shore-based targets, with "79 T" involved in the shelling of Porto Corsini near Ravenna. During that action, an Italian shore battery returned fire, hitting the light cruiser and damaging one of the other 250t-class boats. In late November 1915, the Austro-Hungarian fleet deployed a force from its main fleet base at Pola to Cattaro in the southern Adriatic; this force included six of the eight T-group torpedo boats, so it is possible that one of these was "79 T". This force was tasked to maintain a permanent patrol of the Albanian coastline and interdict any troop transports crossing from Italy.