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). This design would have been a larger and better-armed vessel than the existing Austro-Hungarian 400-tonne (390-long-ton) Huszár-class destroyers.^[3] The specification for the high seas torpedo boat was based on an expectation that the Strait of Otranto, where the Adriatic Sea meets the Ionian Sea, would be blockaded by hostile forces during a future conflict. 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. Steam turbine power was selected for propulsion, as diesels with the necessary power were not available, and the Austro-Hungarian Navy did not have the practical experience to run turbo-electric boats.^[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).^[1] Stabilimento Tecnico Triestino (STT) of Triest was selected for the contract to build the first eight vessels, designated as the T-group. Another tender was requested for four more boats, but when Ganz & Danubius reduced their price by ten per cent, a total of sixteen boats were ordered from them, designated the F-group.^[2] The F-group designation signified the location of Ganz & Danubius' main shipyard at Fiume.^[4]

The 250t-class F-group boats had short raised forecastles and an open bridge, and were fast and agile, well designed for service in the Adriatic.^[5] They had a waterline length of 58.76 metres (192 ft 9 in), a beam of 5.84 m (19 ft 2 in), and a normal draught of 1.5 m (4 ft 11 in). While their designed displacement was 243.9 t (240 long tons), they displaced 267 tonnes (263 long tons) fully loaded.^[6] The boats were powered by two AEG-Curtis steam turbines driving two propellers, using steam generated by two Yarrow water-tube boilers,^[2] one of which burned fuel oil and the other coal.^[4] There were two boiler rooms, one behind the other.^[7] The turbines were rated at 5,000 shaft horsepower (3,700 kW) with a maximum output of 6,000 shp (4,500 kW) and were designed to propel the boats to a top speed of 28–29 kn (52–54 km/h; 32–33 mph).^[6] They carried 20.2 tonnes (19.9 long tons) of coal and 31 tonnes (30.5 long tons) of fuel oil, which gave them a range of 1,200 nautical miles (2,200 km; 1,400 mi) at 16 kn (30 km/h; 18 mph).^[7] The F-group had two funnels rather than the single funnel of the T-group.^[2] 79 T and the rest of the 250t class were classified as high seas torpedo boats by the Austro-Hungarian Navy, despite being smaller than the original concept for a coastal torpedo boat.^[1][8] The naval historian Zvonimir Freivogel states that this type of situation was common due to the parsimony of the Austro-Hungarian Navy.^[1] They were the first small Austro-Hungarian Navy boats to use turbines, and this contributed to ongoing problems with them,^[2] which had to be progressively solved once they were in service.^[5] The crew consisted of three officers and thirty-eight enlisted men.^[9] The vessel carried one 4 m (13 ft) yawl as a ship's boat.^[10]

The boats were armed with two Škoda 66 mm (2.6 in) L/30^[a] guns, with the forward gun mounted on the forecastle, and the aft gun on the quarterdeck.^[7] A 40 cm (16 in) searchlight was mounted above the bridge.^[12] They were also armed with four 450 mm (17.7 in) torpedo tubes mounted in pairs, with one pair mounted between the forecastle and bridge, and the other aft of the mainmast.^[7] One 8 mm (0.31 in) Schwarzlose M.7/12 machine gun was carried for anti-aircraft work. Four mounting points were installed so that the machine gun could be mounted in the most effective position depending on the expected direction of attack.^[13] They could also carry 10–12 naval mines.^[4]

97 F was the sixteenth and last boat of the F-group to be completed. She was laid down at Fiume on 5 March 1915, launched on 20 August 1916 and commissioned on 9 December.^[13]

World War I edit

The original concept of operation for the 250t-class boats was that they would sail in a flotilla at the rear of a cruising battle formation, and were to intervene in fighting only if the battleships around which the formation was established were disabled, or in order to attack damaged enemy battleships.^[14] When a torpedo attack was ordered, it was to be led by a scout cruiser, supported by two destroyers to repel any enemy torpedo boats. A group of four to six torpedo boats would deliver the attack under the direction of the flotilla commander.^[15]

In 1917, one of 97's 66 mm guns may have been placed on an anti-aircraft mount. According to the naval historian Zvonimir Freivogel, sources vary on whether these mounts were added to all boats of the class, and on whether these mounts were added to the forward or aft gun.^[16] In March, 97 was allocated to the 5th Torpedo Boat Group of the 5th Torpedo Boat Division of the 1st Torpedo Flotilla, which was led by the scout cruiser Helgoland.^[17] On 14 July, the boat was sent to the Bocche. On 28 September, 97 supported an air attack on Brindisi in southern Italy.^[18] On 29 November, 97, 83, 96 and the Huszár-class destroyer Csikós were escorting the steamer Dalmatia when the convoy was attacked by a submarine just west of the mouth of the Bojana river, which forms the border between Montenegro and Albania. All four torpedoes missed.^[19] During 1917, 97 escorted thirty-six convoys.^[18]

On 9 January 1918, 97 was damaged by heavy seas, and was sent for repairs.^[18] On 24 May, 97, along with her sisters 77 and 78, and the Kaiman-class boats 58 and 59, pursued an unidentified British submarine near the island of Galijola in the mid-Adriatic.^[20] On 1 February 1918, a mutiny broke out among the sailors of some vessels of the Austro-Hungarian Navy at the Đenovići anchorage within the Bocche, largely over poor food, lack of replacement uniforms and supplies, and insufficient leave, although the poor state of the Austro-Hungarian economy and its impact on their families was also a factor. While 97 was in the Bocche, she was undergoing boiler cleaning at the arsenal at Teodo at the time and her crew did not join the revolt, which was suppressed the following day.^[21]

By 1918, the Allies had strengthened their ongoing blockade on the Strait of Otranto, as foreseen by the Austro-Hungarian Navy. As a result, it was becoming more difficult for the German and Austro-Hungarian U-boats to get through the strait and into the Mediterranean Sea. In response to these blockades, the new commander of the Austro-Hungarian Navy, Konteradmiral Miklós Horthy, decided to launch an attack on the Allied defenders with battleships, scout cruisers, and destroyers.^[22] During the night of 8 June, Horthy left Pola in the upper Adriatic with the dreadnought battleships Viribus Unitis and Prinz Eugen,^[23] with an escort that included 97.^[24] At about 23:00 on 9 June, after some difficulties getting the harbour defence barrage opened, the dreadnoughts Szent István and Tegetthoff,^[23] with an escort force, also departed Pola and set course for Slano, north of Ragusa, to rendezvous with Horthy in preparation for a coordinated attack on the Otranto Barrage. About 03:15 on 10 June,^[b] while returning from an uneventful patrol off the Dalmatian coast, two Royal Italian Navy (Italian: Regia Marina) MAS boats, MAS 15 and MAS 21, spotted the smoke from the Austrian ships. Both boats successfully penetrated the escort screen and split to engage the dreadnoughts individually. MAS 21 attacked Tegetthoff, but her torpedoes missed.^[26] Under the command of Luigi Rizzo, MAS 15 fired two torpedoes at 03:25, both of which hit Szent István. Both boats evaded pursuit. The torpedo hits on Szent István were abreast her boiler rooms, which flooded, knocking out power to the pumps. Szent István capsized less than three hours after being torpedoed.^[25] This disaster essentially ended major Austro-Hungarian fleet operations in the Adriatic for the remaining months of the war.^[27]

On 12-13 June, 97 covered the salvage of the Austro-Hungarian submarine SM U-10 which had been stranded. On 22 July, 97 escorted the minelayer Chamäleon. On 8 September, 97 was based at the Bocche again.^[18] On 14 October, 97 was part of a force which included her sisters 76, 88, and 100, providing anti-aircraft cover for the steamship Brünn as the latter was attempting to free the stranded hospital ship Oceania. Oceania had struck a mine and her crew had beached her off Cape Rodoni in Albania. The attempt was unsuccessful, and Oceania was abandoned.^[28] During 1918, 97 conducted seven anti-submarine patrols and escorted forty-three convoys.^[18] As the end of the war approached and the Austro-Hungarian Empire broke apart, on 1 November 96 was ceded to the State of Slovenes, Croats and Serbs,^[29] which was a short-lived fragment of the empire which united with the Kingdom of Serbia and Kingdom of Montenegro on 1 December, becoming the Kingdom of Serbs, Croats and Slovenes (from 1929, the Kingdom of Yugoslavia).^[30]

Interwar period edit

The Austro-Hungarian Empire sued for peace in November 1918, and 97 survived the war intact.^[2] Immediately after the Austro-Hungarian capitulation, French troops occupied the Bocche, which was treated by the Allies as Austro-Hungarian territory.^[31] During the French occupation, the captured Austro-Hungarian Navy ships moored at the Bocche were neglected, and 97's original torpedo tubes were destroyed or damaged by French troops.^[32] In 1920, under the terms of the previous year's Treaty of Saint-Germain-en-Laye, by which rump Austria officially ended World War I, she was allocated to the Kingdom of Serbs, Croats and Slovenes (KSCS, later Yugoslavia).^[33] Along with three other 250t-class F-group boats, 87, 93 and 96, and four 250t-class T-group boats, she served with the Royal Yugoslav Navy (Serbo-Croatian Latin: Kraljevska Mornarica, KM; Краљевска Морнарица). Taken over in March 1921 when French forces withdrew,^[33][32] in KM service, 97 was renamed T8.^[4] When the navy was formed, she and the other seven 250t-class boats were the only modern sea-going vessels in the KM.^[34] New torpedo tubes of the same size were ordered from the Strojne Tovarne factory in Ljubljana.^[9]

In KM service it was intended to replace one or both guns on each boat of the 250t class with a longer Škoda 66 mm L/45 gun, and according to Freivogel this included the forward gun on T1. She was also fitted with one or two Zbrojovka 15 mm (0.59 in) machine guns. In KM service, the crew increased to 52,^[9] and she was commissioned in 1923.^[35] In 1925, exercises were conducted off the Dalmatian coast, involving the majority of the navy.^[36] In May and June 1929, six of the eight 250t-class torpedo boats – including T8 – accompanied the light cruiser Dalmacija, the submarine tender Hvar and the submarines Hrabri and Nebojša, on a cruise to Malta, the Greek island of Corfu in the Ionian Sea, and Bizerte in the French protectorate of Tunisia.^[37] The ships and crews made a very good impression on the Royal Navy while visiting Malta.^[38] In 1932, the British naval attaché reported that Yugoslav ships engaged in few exercises, manoeuvres or gunnery training due to reduced budgets.^[39]

World War II edit

In April 1941, Yugoslavia entered World War II when it was invaded by the German-led Axis powers. At the time of the invasion, T8 was located at the Bay of Kotor along with her sister ship T1 (formerly 76). The two boats were formally part of the 3rd Torpedo Division, but they were left at Kotor when the rest of the division was deployed to the central Dalmatian port of Šibenik just prior to the invasion, in accordance with a plan to attack the Italian enclave of Zara in northern Dalmatia, which was quickly cancelled.^[40] T8 was under repair at the time of the invasion,^[41] and was captured by the Italian Navy at the Bay of Kotor shortly after the Yugoslav capitulation and was operated by them under her Yugoslav designation, conducting coastal and second-line escort duties in the Adriatic. Her guns were replaced by two 76.2 mm (3 in) L/40 anti-aircraft guns,^[42] and her bridge was enclosed.^[5] She was allocated to Maridalmazia, the military maritime command of Dalmatia (Comando militare maritime della Dalmatia), which was responsible for the area from the northern Adriatic island of Premuda south to the port of Bar in the Italian governorate of Montenegro.^[43]

The Italians capitulated in September 1943, and by this time, T8 was being utilised at Dubrovnik in southern Dalmatia as a guard ship. On 8 September, T8 returned from escorting a convoy to Durazzo in Albania. On 9 September she received orders to support Italian Army operations aimed at preventing the Germans from securing the Dalmatian coast, with a secondary role to escort ships with evacuating personnel. At 22:00, the commander of the Dubrovnik Naval District, Capitano di vascello^[c] Alfredo Bernardinelli, came aboard T8 and the boat patrolled to the island of Korčula. After providing cover for vessels fleeing from the islands of Korčula and Mljet and the ports of Ploče and Gruž, the boat intended to return to Dubrovnik, but it had been occupied by the Germans and the boat and its crew faced capture. Bernardinelli and the boat's captain decided to escape from the Germans by sailing via the island of Lastovo – where they planned to replenish boiler water – to Italy, but around 16:00 on 11 September, while T8 was passing between the islets of Olipa and Jakljan in the Elaphiti Islands off southern Dalmatia, she was attacked by nine German Junkers Ju 87 "Stuka" divebombers and was sunk in a few minutes. About half of her crew died, along with Bernardinelli and her captain, and many were wounded. Survivors were rescued by local Partisans who brought them to Lastovo. They were evacuated from Lastovo to Bari in Allied-held Italy on 23 September on the hospital ship Lubiana.^[45][46]

• List of ships of the Royal Yugoslav Navy