All 27 boats saw service in World War I, undertaking anti-submarine operations in the Adriatic Sea, shore bombardment missions along its Italian coastline, and convoy, escort and minesweeping tasks.

Under the terms of the post-war Treaty of Saint-Germain-en-Laye, the boats were transferred to various countries, including seven to Romania, six to Portugal, six to Greece, and eight to the newly created Kingdom of Serbs, Croats and Slovenes (later Yugoslavia).

During World War II, the five remaining Greek boats were sunk by Axis aircraft during the German-led invasion of Greece in April 1941.

The six surviving Yugoslav boats were captured by the Italians during the Axis invasion of Yugoslavia in April 1941, and were operated by the Regia Marina in a coastal and second-line escort role.

In 1910, the Austria-Hungary Naval Technical Committee initiated the design and development of a 275-tonne (271-long-ton) coastal torpedo boat, specifying that it should be capable of sustaining 30 knots (56 km/h; 35 mph) for 10 hours.

[1][2] At the same time, the committee issued design parameters for a high seas or fleet torpedo boat of 500–550 t (490–540 long tons), top speed of 30 kn and endurance of 480 nautical miles (890 km; 550 mi).

In such circumstances, there would be a need for a torpedo boat that could sail from the Austro-Hungarian Navy (German: kaiserliche und königliche Kriegsmarine, Hungarian: Császári és Királyi Haditengerészet) base at the Bocche di Cattaro (the Bocche or Bay of Kotor) to the strait during the night, locate and attack blockading ships and return to port before morning.

[2] Despite having developed these ideas, the Austro-Hungarian Navy then asked shipyards to submit proposals for a 250 t (250-long-ton) boat with a maximum speed of 28 kn (52 km/h; 32 mph).

They were installed on anti-torpedo boat (Torpedobootabwehrgeschütze or TAG) mounts – fore and aft – without gun shields, and fired a 5.78 kg (12.7 lb) shell at a muzzle velocity of 550 m/s (1,800 ft/s) to a maximum range of 7,000 m (4.3 mi) at an elevation of 25 degrees.

[27] In the latter action, an Italian 120 mm (4.7 in) shore battery returned fire, hitting Novara,[29] killing six and wounding ten,[30] and also damaging 80 T,[29] which had not entered the harbour.

[35] A seaplane attack on Ancona on 9 December was supported by 79 T, 85 F and 87 F, accompanying the protected cruiser Szigetvár, two destroyers and two Kaiman-class torpedo boats.

[37] On 3 February 1916, 83 F, 87 F and 88 F were involved in another shore bombardment operation against targets near San Vito Chietino and the railway line between Ortona and Tollo, this time led by the armoured cruiser Sankt Georg accompanied by Helgoland and the Huszár-class destroyer Wildfang.

This bombardment was conducted as part of the transfer of these ships between Pola and the Bocche, and included an artillery duel between Sankt Georg and an Italian armed train equipped with 4.7 in guns manned by naval personnel.

[32][38] Three days later, Wildfang was south of the Bocche awaiting the return of seaplanes from a mission when the British light cruiser HMS Liverpool and the Italian Rosolino Pilo-class destroyer Pilade Bronzetti appeared.

[39] On the night of 31 May – 1 June 1916, the Tátra-class destroyers Orjen and Balaton, accompanied by 77 T, 79 T and 81 T were sent to engage sea traffic across the Strait of Otranto in the area of the Allied naval blockade.

Near Fasano,[42] they raided the Otranto Barrage,[43] and Orjen engaged in a gunnery duel with the British drifter Beneficent then sank her with a torpedo,[42] but once the alarm had been raised, the Austro-Hungarian force withdrew.

In the exchange of fire, Zeffiro was damaged and the Italians had to retire, pursued by 93 F, 98 M and 99 M.[44] On 3 July, 83 F, 85 F, 87 F accompanied Helgoland and three destroyers in a fruitless raid on the Otranto Barrage.

[45] On 9 July, Novara led a force which included 87 F and two Kaiman-class torpedo boats in another night raid on the Otranto Barrage which resulted in the sinking of two drifters.

A further group of Allied vessels led by the Italian protected cruiser Nino Bixio and HMS Liverpool, accompanied by four destroyers and six torpedo boats.

[19] The Austro-Hungarians sent a large force of four cruisers and five destroyers, accompanied by 83 F, 85 F, 87 F and 88 F, to sail off the Italian coast on 28 August, hoping to draw the Allied fleet into a trap formed by four submarines, but fog meant they were not seen, and no engagements resulted.

The British captain had kept his submarine's periscope extended too far and for too long, and the tell-tale "feather" alerted the crew of 78 T, allowing her to avoid the incoming torpedoes.

[56] On 3 June, the destroyers Wildfang and Csikós, along with 93 and 96, briefly encountered three Italian MAS boats off the mouth of the Tagliamento river in the far north of the Adriatic.

[52] This group, with the addition of the destroyer Velebit, was supporting an attack by six seaplanes on the Italian coast that night when Wildfang struck a mine about 30 nmi (56 km; 35 mi) southwest of Cape Penada on the island of Veliki Brijun off Istria.

During the July build-up to the Eleventh Battle of the Isonzo, there were several seaplane attacks on the coastal areas of the Italian front in the northern Adriatic which were supported by the Austro-Hungarian fleet.

In the south, 82, 91, 92 and 94 and five seaplanes acted as scouts for a raid led by Helgoland accompanied by six destroyers, and further north and later in the day, 82, 87, 91, 92, 94 and 95 were part of an escort for a convoy running supplies to Pirano destined for the troops on the Italian Front.

Two days later, the coastal defence ships Wien and Budapest sailed to engage a 152 mm (6.0 in) Italian shore battery at Cortellazzo near the mouth of the Piave, with an escort that included 84, 92, 94, 98 – 100 and some minesweepers.

[61] On 10 June, 76 – 79, 81 and 87 were part of the escort force that failed to protect the Austro-Hungarian dreadnought Szent István from the Italian MAS boats that sank her.

[7] At the time of the Axis invasion of Yugoslavia in April 1941, the Yugoslav boats T1 and T3 were assigned to the Southern Sector of Coastal Defence Command based at the Bay of Kotor, along with several minesweepers and other craft.

[6] The three Romanian boats were initially deployed against the Soviet Navy Black Sea Fleet following the launch of Operation Barbarossa in June 1941.

Sborul and Smeul survived World War II,[74] having been transferred to the Soviet Black Sea Fleet in late August 1944 after Romania changed sides and joined the Allies, serving as Musson and Toros respectively.