View source for 250t-class torpedo boat

{{short description|Boat of the Austro-Hungarian Navy}}
{{featured article}}

{{Use dmy dates|date=April 2015}}
{{Use shortened footnotes|date=January 2023}}
{|{{Infobox ship begin |sclass=2}} <!-- warships except submarines -->
|+250t-class<br>torpedo boat
{{Infobox ship image
|Ship image=[[File:Austro-Hungarian torpedo boat 81T NH 87683.tif|300px|alt=a black and white photograph of a small ship underway]]
|Ship caption=One of the T-group boats of the 250t class, ''81&nbsp;T''
}}
{{Infobox ship class overview
|Builders=* '''T-group'''
* [[Stabilimento Tecnico Triestino]]
* '''F-group'''
* [[Ganz Works|Ganz & Danubius]]
* '''M-group'''
* [[Cantiere Navale Triestino]]

|Operators=* {{navy|Austria–Hungary}}
* {{flagdeco|Kingdom of Yugoslavia}} Navy of the [[Kingdom of Serbs, Croats and Slovenes]]
* {{flagicon image|Naval Ensign of Romania (1922–1947).svg}} [[Romanian Naval Forces]]
* {{navy|Portugal}}
* {{navy|Greece|royalnavy}}
* {{navy|Kingdom of Yugoslavia}}
* {{navy|Kingdom of Italy}}
* {{navy|Nazi Germany}}
* {{navy|NDH}}
* {{navy|Soviet Union}}
* {{navy|Yugoslavia}}

|Class before={{sclass2|110t|torpedo boat}}
|Class after=
|Subclasses=
|Built range=1913–1916
|In commission range=1914–1963
|Total ships completed=27
|Total ships lost=15
|Total ships scrapped=12
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=
|Ship type=Sea-going [[torpedo boat]]
|Ship displacement=*{{convert|262|-|270|t|LT|0|lk=out|abbr=on}}
* {{convert|320|-|330|t|LT|0|abbr=on}} (full load)

|Ship length={{convert|58.2|-|60.5|m|ftin|abbr=on}}
|Ship beam={{convert|5.6|-|5.8|m|ftin|abbr=on}}
|Ship draught={{convert|1.5|m|abbr=on}} (all groups)
|Ship power=*2 × [[Yarrow boiler|Yarrow]] boilers
* {{convert|5000|-|6000|shp|lk=in|abbr=on}}
|Ship propulsion=*2 × shafts
* 2 × [[steam turbine]]s
|Ship speed={{convert|28|-|28.5|kn}}
|Ship range=
|Ship endurance=* '''T-group'''
* {{convert|980|nmi|abbr=on}} at {{convert|16|kn}}
* '''F-group and M-group'''
* {{convert|1200|nmi|abbr=on}} at {{convert|16|kn}}

|Ship complement=38–39
|Ship sensors=
|Ship EW=
|Ship armament=*2 × [[Škoda Works|Škoda]] [[Škoda 7 cm guns|{{convert|66|mm|in|sp=us|abbr=on}}]] L/30 guns
* 4 × {{convert|450|mm|in|abbr=on|sigfig=3}} [[torpedo tubes]]
* 10–12 [[naval mine]]s
|Ship notes=
}}
|}

The '''250t class''' were high-seas [[torpedo boat]]s built for the [[Austro-Hungarian Navy]] between 1913 and 1916. A total of 27 boats were built by three shipbuilding companies, with the letter after the boat number indicating the manufacturer. There were small variations between manufacturers, mainly in the [[steam turbine]]s used, and whether they had one or two [[funnel (ship)|funnels]]. The eight boats of the T-group, designated ''74&nbsp;T''&nbsp;– ''81&nbsp;T'', were built by [[Stabilimento Tecnico Triestino]], located at [[Trieste|Triest]]. The sixteen boats of the F-group, ''82&nbsp;F''&nbsp;– ''97&nbsp;F'', were built by [[Ganz Works|Ganz-Danubius]] at their shipyards at [[Rijeka|Fiume]] and [[Kraljevica|Porto Re]]. The three M-group boats,  ''98&nbsp;M''&nbsp;– ''100&nbsp;M'', were manufactured by [[Cantiere Navale Triestino]] at [[Monfalcone]].

All 27 boats saw service in [[World War I]], undertaking [[Anti-submarine warfare|anti-submarine operations]] in the [[Adriatic Sea]], [[shore bombardment]] missions along its Italian coastline, and [[convoy]], escort and [[minesweeping]] tasks. Although widely used during the war, the class suffered no losses, despite taking hits during surface engagements and damage from accidents. In 1917, some of the {{convert|66|mm|in|abbr=on}} guns on the boats were placed on [[anti-aircraft warfare|anti-aircraft]] mounts. Under the terms of the post-war [[Treaty of Saint-Germain-en-Laye (1919)|Treaty of Saint-Germain-en-Laye]], the boats were transferred to various countries, including seven to [[Kingdom of Romania|Romania]], six to [[First Portuguese Republic|Portugal]], six to [[Kingdom of Greece|Greece]], and eight to the newly created [[Kingdom of Yugoslavia|Kingdom of Serbs, Croats and Slovenes]] (later Yugoslavia). By 1940, thirteen boats of the class had been lost or [[Ship breaking|scrapped]], including all six Portuguese boats.

During [[World War II]], the five remaining Greek boats were sunk by [[Axis powers|Axis]] aircraft during the [[Nazi Germany|German]]-led [[Battle of Greece|invasion of Greece]] in April 1941.  One Romanian boat was lost during the war, while the two remaining Romanian boats performed escort tasks in the [[Black Sea]] before being taken over by the [[Soviet Navy]], and serving in the [[Black Sea Fleet]] until the end of the war; they were finally stricken in late 1945.

The six surviving Yugoslav boats were captured by the [[Kingdom of Italy|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. Immediately following the Italian [[Armistice of Cassibile|capitulation]] in September 1943, one ex-Yugoslav boat was sunk by German aircraft while attempting to escape to [[Allies of World War II|Allied]]-held southern Italy, another was [[Scuttling|scuttled]] by its Italian crew when it had insufficient fuel to escape, and two more escaped and were transferred back into Yugoslav hands a few months later. The remaining two were seized by the Germans. Of these, both were operated by Croatian crews or by the [[Navy of the Independent State of Croatia]] for some time before being recovered by the Germans. One was destroyed by [[Royal Navy]] [[Motor Torpedo Boat]]s in June 1944, and the other was sunk by [[Royal Air Force]] aircraft in 1945. The two surviving boats were commissioned by the [[Yugoslav Navy]] after the war, one continuing in service until the early 1960s.
{{TOC level|3}}

==Background==
In 1910, the [[Austria-Hungary]] Naval Technical Committee initiated the design and development of a {{convert|275|t|LT|adj=on|lk=on}} coastal [[torpedo boat]], specifying that it should be capable of sustaining {{convert|30|kn|lk=in}} for 10 hours.{{sfn|Freivogel|2022|p=60}}{{sfn|Gardiner|1985|p=339}} At the same time, the committee issued design parameters for a high seas or fleet torpedo boat of {{cvt|500|-|550|t|LT}}, top speed of 30&nbsp;kn and endurance of {{convert|480|nmi}}. This design would have been a larger and better-armed vessel than the existing Austro-Hungarian {{convert|400|t|LT|adj=on}} {{sclass|Huszár|destroyer}}s.{{sfn|Freivogel|2022|p=59}} 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 [[blockade]]d 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]] ({{langx|de|kaiserliche und königliche Kriegsmarine|links=no}}, {{langx|hu|Császári és Királyi Haditengerészet|links=no}}) base at the [[Bay of Kotor|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 [[Marine propulsion#Reciprocating|diesels]] with the necessary power were not available, and the Austro-Hungarian Navy did not have the practical experience to run [[Turbo-electric transmission|turbo-electric]] boats.{{sfn|Gardiner|1985|p=339}} Despite having developed these ideas, the Austro-Hungarian Navy then asked shipyards to submit proposals for a {{cvt|250|t|LT|adj=on}} boat with a maximum speed of {{cvt|28|kn}}.{{sfn|Freivogel|2022|p=60}}

==Description and construction==
[[Stabilimento Tecnico Triestino]] (STT) of [[Trieste|Triest]] was selected for the contract to build eight vessels, ahead of one other tenderer. 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.{{sfn|Freivogel|2022|p=60}}{{sfn|O'Hara|Worth|Dickson|2013|pp=26–27}} The naval historian Zvonimir Freivogel states that this type of situation was common due to the parsimony of the Austro-Hungarian Navy.{{sfn|Freivogel|2022|p=60}} The STT boats used [[Parsons Marine Steam Turbine Company|Parsons]] turbines driving two [[drive shaft|propeller shafts]].{{sfn|Greger|1976|p=58}} Another tender was requested for four more boats, but when [[Ganz Works|Ganz-Danubius]] reduced their price by ten percent, a total of sixteen boats were ordered from them. These boats were powered by [[AEG (German company)|AEG]]-Curtiss turbines, and had two [[Funnel (ship)|funnels]] rather than the single funnel of the STT boats.{{sfn|Gardiner|1985|p=339}} The third contract went to [[Cantiere Navale Triestino]] (CNT), who used Melms-Pfenniger turbines, and their boats also had two funnels.{{sfn|Greger|1976|p=63}} The boats of all three groups used steam generated by two [[Yarrow boiler|Yarrow]] [[water-tube boiler]]s, one of which burned [[fuel oil]] and the other coal.{{sfn|Greger|1976|pp=58, 60 & 63}}

The boats of the class were fast and agile, well designed for service in the Adriatic.{{sfn|Freivogel|2020|p=102}} The M-group boats were longer overall and had a longer [[forecastle]] than the T- and F- group boats. All boats of the class had a slight flare at the [[bow (watercraft)|bow]], a straight [[stem (ship)|stem]] and [[keel]], and a rounded [[stern]]. Until October 1915, the boats were painted black, but from that point they were painted a light blue-grey. The [[hull (watercraft)|hull]]s were built with a series of 13 transverse [[Bulkhead (partition)|bulkhead]]s dividing them into 14 watertight compartments. The forward collision compartment and anchor chain locker were in the [[bow (watercraft)|fore]], [[Glossary of nautical terms (A–L)#abaft|abaft]] of which were two larger accommodation compartments for the [[enlisted ranks|enlisted crew]], then the forward and [[aft]] [[boiler room (ship)|boiler rooms]], the forward and aft turbine rooms, accommodation for officers and [[non-commissioned officer]]s, and the equipment room was located in the stern. The first two groups had a semi-[[Balanced rudder#ships|balanced]] [[rudder]], whereas the M-group boats had a fully balanced rudder.{{sfn|Freivogel|2022|p=65}}   

The T-group boats were originally to be armed with three {{convert|66|mm|in|sp=us|abbr=on}} guns, and three {{convert|450|mm|in|abbr=on|sigfig=3}} [[torpedo tube]]s{{snd}}one twin and one single{{snd}}but this was changed to two guns and four torpedo tubes{{snd}}consisting of two twin mountings{{sfn|Freivogel|2022|p=60}}{{snd}}before the first boat was completed, to standardise the armament with the F group to follow.{{sfn|Greger|1976|p=58}} When completed, all 27 boats were armed with two [[Škoda Works|Škoda]] [[Škoda 7 cm guns|{{convert|66|mm|in|sp=us|abbr=on}}]] L/30{{efn|L/30 denotes the length of the gun. In this case, the L/30 gun is 30 [[Caliber (artillery)|calibre]], meaning that the gun was 30 times as long as the diameter of its bore.}} guns. They were installed on anti-torpedo boat ({{lang|de|Torpedobootabwehrgeschütze}} or TAG) mounts{{snd}}fore and aft{{snd}}without [[gun shield]]s, and fired a {{cvt|5.78|kg|lb|adj=on}} shell at a [[muzzle velocity]] of {{cvt|550|m/s}} to a maximum range of {{cvt|7000|m|mi}} at an elevation of 25 degrees. A total of 216 shells were carried for each gun.{{sfn|Freivogel|2022|p=66}} On the T- and F- group boats, the forward torpedo tubes were mounted between the [[forecastle]] and [[bridge (nautical)|bridge]], and on the M-group boats, they were mounted on the aft section of the extended forecastle. On the T-group boats the aft torpedo tubes were located directly [[Glossary of nautical terms (A–L)#abaft|abaft]] the [[Mast (sailing)#Nomenclature|mainmast]], and on the F-group boats they were mounted on the [[quarterdeck]], abaft the [[ship's boat]]. On the M group boats, the aft torpedo tubes were mounted immediately forward of the aft mast.{{sfn|Freivogel|2022|p=65}} The torpedo tubes were manufactured by the [[Whitehead torpedo|Whitehead]] factory in Fiume, and fired the Whitehead 450&nbsp;mm L/5 torpedo, which was {{cvt|5.5|m|ftin}} long and weighed {{cvt|772|kg|lb}} with a {{cvt|110|kg|lb|adj=on}} warhead. At a range of {{cvt|1000|m}} the torpedo could reach a maximum speed of {{cvt|42|kn}}, and at a range of {{cvt|6000|m}} they could travel at {{cvt|27|kn}}.{{sfn|Freivogel|2022|p=69}} A {{cvt|40|cm|adj=on}} [[searchlight]] was mounted above the [[bridge (nautical)|bridge]].{{sfn|Freivogel|2022|pp=64–65}} In July 1914, one {{convert|8|mm|in|abbr=on}} [[Schwarzlose machine gun|Schwarzlose M.7/12 machine gun]] was included in the armament of all boats of the class for [[anti-aircraft warfare|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.{{sfn|Freivogel|2022|p=67}} Each vessel could carry 10–12 [[naval mine]]s.{{sfn|Greger|1976|p=58}}

===T-group===
The T-group were built by STT at the [[Port of Trieste|Port of Triest]] between April 1913 and December 1914.{{sfn|Freivogel|2022|p=61}} They had a [[waterline length]] of {{convert|57.84|m|ftin|abbr=on}}, a [[Beam (nautical)|beam]] of {{convert|5.75|m|ftin|abbr=on}}, and a normal [[Draft (hull)|draught]] of {{convert|1.54|m|ftin|abbr=on}}. While their designed displacement was {{convert|262|t|LT|0}}, they displaced about {{convert|267.3|t|LT}} fully loaded.{{sfn|Freivogel|2022|p=65}} Their Parsons turbines were rated at {{convert|5000|-|5700|shp|lk=in|abbr=on}} and designed to propel the boats to a top speed of {{convert|28|kn}}. They carried {{convert|18.2|t|LT|sigfig=3}} of coal and {{convert|24.3|t|LT|sigfig=3}} of fuel oil, which gave them a range of {{convert|1000|nmi|lk=in|abbr=on}} at {{convert|16|kn}}.{{sfn|Freivogel|2020|pp=102–103}}

The boats were originally to be armed with three {{convert|66|mm|in|sp=us|abbr=on}} guns, and three {{convert|450|mm|in|abbr=on|sigfig=3}} torpedo tubes{{snd}}one twin and one single{{snd}}but this was changed to two guns and four torpedo tubes{{snd}}consisting of two twin mountings{{sfn|Freivogel|2022|p=60}}{{snd}}before the first boat was completed, to standardise the armament with the F group to follow.{{sfn|Greger|1976|p=58}} The torpedo tubes were mounted in pairs, with one pair mounted between the forecastle and bridge, and the other on a section of raised superstructure above the aft machinery room.{{sfn|Freivogel|2020|pp=102–103}}

{|class="wikitable sortable plainrowheaders" style="text-align: center;"
|+ Construction of T-group torpedo boats{{sfn|Freivogel|2022|p=61}}
|-
! scope="col" | Name
! scope="col" | Laid down
! scope="col" | Launched
! scope="col" | Commissioned
|-
! scope="row" | ''74&nbsp;T''
| 16 April 1913 || 28 August 1913 || 17 June 1914
|-
! scope="row" | ''75&nbsp;T''
| 28 May 1913 || 20 November 1913 || 11 July 1914
|-
! scope="row" | [[Yugoslav torpedo boat T1|''76&nbsp;T'']]
| 24 August 1913 || 15 December 1913 || 20 July 1914
|-
! scope="row" | [[Yugoslav torpedo boat T2|''77&nbsp;T'']]
| 24 August 1913 || 30 January 1914 || 11 August 1914
|-
! scope="row" | [[Yugoslav torpedo boat T3|''78&nbsp;T'']]
| 22 October 1913 || 4 March 1914 || 23 August 1914
|-
! scope="row" | [[Yugoslav torpedo boat T4|''79&nbsp;T'']]
| 1 December 1913 || 30 April 1914 || 1 October 1914
|-
! scope="row" | ''80&nbsp;T''
| 19 December 1913 || 3 August 1914 || 8 November 1914
|-
! scope="row" | ''81&nbsp;T''
| 6 February 1914 || 6 August 1914 || 2 December 1914
|}
When ''74&nbsp;T''{{'}}s turbines were initially installed, they suffered a major problem with heat expansion of the turbine blades, causing friction between the [[Rotor (turbine)|rotor]] and [[stator]] blades. The issue was so significant that her turbines had to be rebuilt, with additional space between the blades and improved fixing of the rotor blades. Having been first commissioned on 1 February 1914, ''74&nbsp;T'' was commissioned for a second time on 17 June. Likewise, the next two boats of the T-group had to have their turbines removed, modified and reinstalled due to these issues.{{sfn|Freivogel|2022|pp=60–61}}

===F-group===
The F-group were built by Ganz & Danubius at [[Rijeka|Fiume]] and nearby [[Kraljevica|Porto Re]] between October 1913 and December 1916. They had a waterline length of {{convert|58.5|m|ftin|abbr=on}}, a beam of {{convert|5.8|m|ftin|abbr=on}}, and a normal draught of {{convert|1.5|m|ftin|abbr=on}}. While their designed displacement was {{convert|266|t|LT|0}}, they displaced about {{convert|330|t|LT}} fully loaded.{{sfn|Greger|1976|p=58}} The crew consisted of 38 officers and enlisted men. Their AEG-Curtiss turbines were rated at {{convert|5000|shp|abbr=on}} with a maximum output of {{convert|6000|shp|abbr=on}}, and the boats were designed to reach a top speed of {{convert|28|kn}}. During trials, ''93&nbsp;F'' produced {{convert|6450|shp|abbr=on}}, and reached a top speed of {{convert|29.7|kn}}. They carried {{convert|20|LT|sigfig=3}} of coal and {{convert|34|LT|sigfig=3}} of fuel oil,{{sfn|Jane's Information Group|1989|p=313}} which gave them a range of {{convert|1200|nmi|abbr=on}} at {{convert|16|kn}}.{{sfn|Greger|1976|p=60}}
[[File:Austro-Hungarian torpedo boat 86F NH 87688.tif|thumb|upright=1.38|The F-group boat ''86&nbsp;F'' alongside the battleship {{SMS|Erzherzog Franz Ferdinand}}|alt=black and white photograph of two vessels alongside each other]]
{|class="wikitable sortable plainrowheaders" style="text-align: center;"
|+ Construction of F-group torpedo boats{{sfn|Greger|1976|p=60}}
|-
! scope="col" | Name
! scope="col" | Laid down
! scope="col" | Launched
! scope="col" | Completed
|-
! scope="row" | [[NMS Năluca|''82 F'']]
| 30 October 1913 || 11 August 1914 || 16 August 1916
|-
! scope="row" | [[NMS Smeul|''83 F'']]
| 17 November 1913 || 7 November 1914 || 7 August 1915
|-
! scope="row" | ''84 F''
| 27 November 1913 || 21 November 1914 || 2 November 1916
|-
! scope="row" | ''85 F''
| 7 January 1914 || 5 December 1914 || 19 December 1915
|-
! scope="row" | ''86 F''
| 26 January 1914 || 19 December 1914 || 23 May 1916
|-
! scope="row" | [[Yugoslav torpedo boat T5|''87 F'']]
| 5 March 1914 || 20 March 1915 || 25 October 1915
|-
! scope="row" | ''88 F''
| 7 March 1914 || 24 April 1915 || 30 November 1915
|-
! scope="row" | ''89 F''
| 13 May 1914 || 12 May 1915 || 1 March 1916
|-
! scope="row" | ''90 F''
| 9 September 1914 || 28 May 1915 || 8 August 1916
|-
! scope="row" | ''91 F''
| 24 November 1914 || 21 June 1916 || 11 July 1916
|-
! scope="row" | [[Greek torpedo boat Panormos|''92 F'']]
| 30 November 1914 || 29 September 1916 || 23 March 1916
|-
! scope="row" | [[Yugoslav torpedo boat T6|''93 F'']]
| 9 January 1915 || 25 November 1915 || 16 April 1916
|-
! scope="row" | [[Greek torpedo boat Proussa|''94 F'']]
| 19 January 1915 || 8 March 1916 || 17 June 1916
|-
! scope="row" | [[Greek torpedo boat Pergamos|''95 F'']]
| 9 February 1915 || 24 June 1916 || 27 September 1916
|-
! scope="row" | [[Yugoslav torpedo boat T7|''96 F'']]
| 24 February 1915 || 7 July 1916 || 23 November 1916
|-
! scope="row" | [[Yugoslav torpedo boat T8|''97 F'']]
| 5 March 1915 || 20 August 1916 || 22 December 1916
|}
When [[Kingdom of Italy|Italy]] declared war on Austria-Hungary in May 1915, five incomplete F-group boats were towed to be completed in safety. ''82&nbsp;F'', ''83&nbsp;F'' and ''84&nbsp;F'' were taken from Porto Re to [[Pula|Pola]], and ''90&nbsp;F'' and ''91&nbsp;F'' were taken to [[Novigrad, Zadar County|Novigrad]]. This resulted in delays to the completion of these boats.{{sfn|Greger|1976|p=60}}

===M-group===
The M-group were built by CNT at [[Monfalcone]] between March 1914 and March 1916. They had a waterline length of {{convert|60.5|m|ftin|abbr=on}}, a beam of {{convert|5.6|m|ftin|abbr=on}}, and a normal draught of {{convert|1.5|m|ftin|abbr=on}}. Their designed displacement was {{convert|270|t|LT|0}}, and they displaced about {{convert|330|t|LT}} fully loaded. The crew consisted of 38 officers and enlisted men. Their Melms-Pfenniger turbines were rated at {{convert|5000|shp|abbr=on}} with a maximum output of {{convert|6000|shp|abbr=on}}, and the boats were designed to reach a top speed of {{convert|28.5|kn}}. They carried enough coal and fuel oil to give them a range of {{convert|1200|nmi|abbr=on}} at {{convert|16|kn}}.{{sfn|Greger|1976|p=63}}

{|class="wikitable sortable plainrowheaders" style="text-align: center;"
|+ Construction of M-group torpedo boats{{sfn|Greger|1976|p=63}}
|-
! scope="col" | Name
! scope="col" | Laid down
! scope="col" | Launched
! scope="col" | Completed
|-
! scope="row" | [[Greek torpedo boat Kyzikos|''98 M'']]
| 19 March 1914 || 18 November 1914 || 19 August 1915
|-
! scope="row" | [[Greek torpedo boat Kios|''99 M'']]
| 22 March 1914 || 17 December 1914 || 29 October 1915
|-
! scope="row" | [[Greek torpedo boat Kydoniai|''100 M'']]
| 28 March 1914 || 15 January 1915 || 13 March 1916
|}

==Service history==

===World War I===
All 27 boats saw service, performing [[convoy]], escort and [[minesweeping]] tasks, [[Anti-submarine warfare|anti-submarine operations]],{{sfn|Gardiner|1985|p=339}} and [[shore bombardment]] missions.{{sfn|Cernuschi|O'Hara|2015|p=171}} They also conducted patrols and supported [[seaplane]] raids against the Italian coast. Due to inadequate funding, the 250t class were essentially coastal vessels, despite the original intention that they would be used for "high seas" operations.{{sfn|O'Hara|Worth|Dickson|2013|pp=26–27}}

====1914====
At the outbreak of [[World War I]], ''74&nbsp;T''&nbsp;– ''77&nbsp;T'' comprised the 1st Torpedo Group of the 3rd Torpedo Division of the Austro-Hungarian 1st Torpedo Flotilla,{{sfn|Greger|1976|pp=11–12}} which was led by the [[scout cruiser]] {{SMS|Saida||2}} commanded by ''[[Linienschiffskapitän]]'' (Captain) Heinrich Seitz, and supported by the [[mother ship]] ''Gäa''.{{sfn|Freivogel|2019|p=70}} The 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 [[battleship]]s around which the formation was established were disabled, or in order to attack damaged enemy battleships.{{sfn|Freivogel|2019|p=68}} 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.{{sfn|Freivogel|2019|p=69}}

In early September 1914, intelligence was received by the Austro-Hungarian command that an Italian volunteer corps were planning to land on the [[Dalmatia]]n or [[Istria]]n coast, and the 1st and 2nd Torpedo Flotillas were involved fruitless patrolling off [[Sebenico]] and [[Zadar|Zara]], and Istria, respectively, between 19 and 24 September. It appears that this was French [[disinformation]] intended to keep the Austro-Hungarian fleet engaged while they conducted operations in the southern Adriatic.{{sfn|Freivogel|2019|p=100}} On the evening of 3 November, the 1st Torpedo Flotilla left Sebenico to make a night torpedo attack on the French fleet, which had begun its seventh raid on the Adriatic on 31 October, but by the time they reached the threatened areas, the French had withdrawn as they were running low on coal.{{sfn|Freivogel|2019|pp=119–120}}

====1915====
Italy declared war on Austria-Hungary on the afternoon of 23 May 1915, and almost the entire Austro-Hungarian fleet left Pola soon after to deliver an immediate response against Italian cities and towns along the Adriatic coast, aiming to interdict land and sea transport between southern Italy and the northern regions of that country which were expected to be a [[Theater (warfare)|theatre]] of land operations. The fleet split into six groups with a range of targets up and down the coast.{{sfn|Freivogel|2019|p=168}} Group A included three [[dreadnought battleship]]s, six [[pre-dreadnought battleship]]s,{{sfn|Cernuschi|O'Hara|2015|p=168}} and four destroyers, accompanied by ''74&nbsp;T''&nbsp;– ''77&nbsp;T'' and ''83&nbsp;F'', fourteen {{sclass|Kaiman|torpedo boat|2}}s and six seaplanes, and participated in the [[Bombardment of Ancona]], a shore bombardment operation against the northern Adriatic coast of Italy.{{sfn|Freivogel|2019|p=168}} The bombardment began at 04:04 on 24 May, and caused significant damage in the shipyard, killing 68, 30 of them military personnel, and wounding 150. The destroyers entered the harbour and launched several torpedoes, sinking one steam ship and damaging two others. Group A withdrew after 05:00 when news was received of Italian submarines leaving [[Venice]] en route to Pola.{{sfn|Freivogel|2019|p=169}} Group E, formed by the [[light cruiser]] {{ship|SMS|Novara|1913|2}}, a destroyer and ''78&nbsp;T''&nbsp;– ''81&nbsp;T'', was involved in the shelling of [[Port of Ravenna|Porto Corsini]] near Ravenna.{{sfn|Cernuschi|O'Hara|2015|p=168}} In the latter action, an Italian {{convert|4.7|in|abbr=on|order=flip}} [[Coastal artillery|shore battery]] returned fire, hitting ''Novara'',{{sfn|Cernuschi|O'Hara|2014|p=1235}} killing six and wounding ten,{{sfn|Freivogel|2019|p=171}} and also damaging ''80&nbsp;T'',{{sfn|Cernuschi|O'Hara|2014|p=1235}} which had not entered the harbour. ''81&nbsp;T'' joined ''Novara'' in shelling the [[semaphore]] station and a [[lighthouse]], and then engaged in the duel with the coastal artillery.{{sfn|Freivogel|2019|p=171}}

The 250t-class torpedo boats continued to be involved in shore bombardment operations. On 23 July, ''77&nbsp;T'' and ''78&nbsp;T'' participated in such a mission led by the scout cruiser {{SMS|Helgoland|1912|2}} against [[Ortona]] on the central Adriatic coast of Italy.{{sfn|Freivogel|2019|p=185}}{{efn|According to Cernuschi and O'Hara, the 23 July operation involved ''74&nbsp;T'' and ''78&nbsp;T'' in a shore bombardment and landing operation led by ''Saida'' against [[San Benedetto del Tronto]], [[Ortona]] and [[Termoli]].{{sfn|Cernuschi|O'Hara|2015|p=169}} Freivogel states that a separate group of destroyers attacked Termoli and [[Campomarino]], and a landing party from two more destroyers cut the [[telegraph]] cable on the [[Tremiti Islands]], and does not mention the involvement of ''Saida''.{{sfn|Freivogel|2019|p=185}} }} Four days later, the scout cruiser {{SMS|Admiral Spaun||2}}, ''Novara'', two destroyers and ''75&nbsp;T'', ''76&nbsp;T'' and ''79&nbsp;T'' shelled the railway line between Ancona and [[Pesaro]] while seaplanes bombed Ancona.{{sfn|Freivogel|2019|p=186}}

On 28 July, ''80&nbsp;T'' and ''81&nbsp;T'' were part of the first major attempt to land on the Italian-occupied island of [[Pelagosa]] in the mid-Adriatic. Led by ''Saida'' and ''Helgoland'', the six {{sclass|Tatra|destroyer|2}}s and two torpedo boats bombarded the island, then landed 108 officers and sailors. The 90-man Italian naval garrison&nbsp;–&nbsp;the size and strength of which had been underestimated by the attacking force&nbsp;–&nbsp;defended bravely, and after two hours the Austro-Hungarian force withdrew, having suffered two killed and ten wounded. Only two Italians were wounded.{{sfn|Freivogel|2019|p=186}} The 1st Torpedo Flotilla, comprising ''Saida'' and ''Helgoland'', five destroyers and five torpedo boats, again attacked Pelagosa on 17 August. ''74&nbsp;T'', ''77&nbsp;T'' and ''78&nbsp;T'' conducted anti-submarine patrols south of the island along with two destroyers. The bombardment was successful, and managed to destroy defences, a large quantity of supplies, and crucially, the [[water cistern]]. This was the final straw for the Italians, who abandoned the island the following day.{{sfn|Freivogel|2019|pp=188–189}}

In late November 1915, the Austro-Hungarian fleet deployed a force from its main fleet base at Pola to the Bocche; this force included six of the T-group torpedo boats. This force was tasked to maintain a permanent patrol of the Albanian coastline and interdict any troop transports crossing from Italy.{{sfn|Halpern|2012|p=229}} A seaplane attack on Ancona on 9 December was supported by ''79&nbsp;T'', ''85&nbsp;F'' and ''87&nbsp;F'', accompanying the protected cruiser {{SMS|Szigetvár||2}}, two destroyers and two ''Kaiman''-class torpedo boats. Another seaplane attack, this time on [[Rimini]] on 14 December, was supported by ''83&nbsp;F'', ''87&nbsp;F'' and ''89&nbsp;F'', along with ''Szigetvár'', two destroyers and two ''Kaiman''-class torpedo boats.{{sfn|Freivogel|2019|p=206}} After an attack on [[Durrës|Durazzo]] in [[Principality of Albania|Albania]] on 30 December in which two Austro-Hungarian destroyers were sunk after straying out of a cleared lane through a minefield, ''74&nbsp;T'', ''77&nbsp;T'', ''78&nbsp;T'', ''80&nbsp;T'' and ''81&nbsp;T'' were sent south with ''Novara'', in order to strengthen morale and try to prevent the transfer of the captured crew of one of the destroyers to Italy. No Italian ships were encountered, and the group returned to the Bocche the following day.{{sfn|Freivogel|2019|p=211}}

====1916====
On 3 February 1916, ''83&nbsp;F'', ''87&nbsp;F'' and ''88&nbsp;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]] {{SMS|Sankt Georg||2}} accompanied by ''Helgoland'' and the ''Huszár''-class destroyer {{SMS|Wildfang||2}}. 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 [[Armoured train|armed train]] equipped with 4.7 in guns manned by naval personnel.{{sfn|Cernuschi|O'Hara|2015|p=169}}{{sfn|Freivogel|2019|p=221}} Three days later, ''Wildfang'' was south of the Bocche awaiting the return of seaplanes from a mission when the British light cruiser {{HMS|Liverpool|1909|6}} and the Italian {{sclass|Rosolino Pilo|destroyer|2}} {{ship|Italian destroyer|Pilade Bronzetti||2}} appeared. ''Wildfang'' engaged in a short exchange of fire under the protection of coastal guns and withdrew. In response to the arrival of ''Liverpool'' and ''Pilade Bronzetti'', ''Helgoland'', ''74&nbsp;T'', ''78&nbsp;T'', ''80&nbsp;T'', ''83&nbsp;F'', ''87&nbsp;F'' and ''88&nbsp;F'' sailed, but they were met by another British light cruiser, {{HMS|Weymouth|1910|6}}, and the French destroyer {{ship|French destroyer|Bouclier||2}}, that had relieved ''Liverpool'' and ''Pilade Bronzetti'' in the intervening period. The Austro-Hungarian torpedo boats, split into two groups, launched torpedo attacks on the new Allied formation, but the only damage was caused by a collision between ''74&nbsp;T'' and ''83&nbsp;F''. The group led by ''74&nbsp;T'' withdrew to [[Budva|Budua]] after the collision, but the other group attacked, scoring no hits. Finally, the Austro-Hungarian ships withdrew to the Bocche, having achieved little, and missed opportunities to attack enemy vessels operating further south.{{sfn|Freivogel|2019|p=221}}{{sfn|Cernuschi|O'Hara|2015|p=170}}

On 22 February, ''76&nbsp;T'', ''77&nbsp;T'' and ''83&nbsp;F'', accompanied by a ''Kaiman''-class torpedo boat, laid a minefield outside Antivari harbour. With Austro-Hungarian forces closing on Durazzo from the land, the Allies began to evacuate by sea, and Austro-Hungarian naval forces were sent to attempt to interdict. On 24 February, ''Helgoland'', four destroyers, ''77&nbsp;T'', ''78&nbsp;T'', ''80&nbsp;T'', ''83&nbsp;T'', ''83&nbsp;F'' and ''88&nbsp;F'' were sent to intercept four Italian destroyers covering the evacuation, but were unable to locate them.{{sfn|Freivogel|2019|pp=221–222}}

On 3 May, ''76&nbsp;T'', ''92&nbsp;F'', ''93&nbsp;F'' and ''98&nbsp;M''&nbsp;– ''100&nbsp;M'' were accompanying four destroyers supporting the return of seaplanes that had attacked Ravenna and Porto Corsini when they were involved in a surface action off Porto Corsini against an Italian force consisting of the [[flotilla leader]]s {{ship|Italian cruiser|Cesare Rossarol||2}} and {{ship|Italian cruiser|Guglielmo Pepe||2}}, and the destroyers {{ship|Italian destroyer|Francesco Nullo|1914|2}} and {{ship|Italian destroyer|Giuseppe Missori||2}}.{{sfn|Cernuschi|O'Hara|2015|p=170}}{{sfn|Freivogel|2019|p=232}} According to the naval historians Enrico Cernuschi and [[Vincent P. O'Hara]], the Austro-Hungarian force retreated behind a minefield with no damage to the torpedo boats, and only [[Fragmentation (weaponry)|splinter]] damage to the ''Huszár''-class destroyer {{SMS|Csikós||2}}.{{sfn|Cernuschi|O'Hara|2015|p=170}} However, a more recent work by the naval historian Zvonimir Freivogel disputes the latter assertion, saying that none of the vessels on either side were damaged.{{sfn|Freivogel|2019|p=232}}

On 24 May, the Allies were anticipating a significant Austro-Hungarian attack from the sea to mark the first anniversary of the Italians entering the war, and a two Allied cruisers and six destroyers were despatched to patrol the area between the Bocche and Brindisi. An Austro-Hungarian force consisting of four destroyers, ''75&nbsp;T'', ''89&nbsp;F'', ''92&nbsp;F'', and ''98&nbsp;M''&nbsp;– ''100&nbsp;M'' was at sea supporting the return of eleven seaplanes that had been sent to attack [[Padua]]. Due to fog, only one of the aircraft had been able to identify and drop bombs on a target there, but on the return trip, one of the aircraft mistakenly dropped three bombs on ''92&nbsp;F'', luckily missing the target. The same aircraft strafed ''100&nbsp;M'' with its machine gun. Two torpedo boats from the Italian force, {{ship|Italian torpedo boat|21 OS||2}} and {{ship|Italian torpedo boat|22 OS||2}} engaged in a  brief exchange of fire with ''75&nbsp;T''.{{sfn|Cernuschi|O'Hara|2015|p=170}}{{sfn|Freivogel|2019|p=235}} During the action, ''75&nbsp;T'' was hit.{{sfn|Cernuschi|O'Hara|2015|p=170}} On the night of 31 May – 1 June 1916, the {{sclass|Tátra|destroyer|2}}s {{SMS|Orjen||2}} and {{SMS|Balaton||2}}, accompanied by ''77&nbsp;T'', ''79&nbsp;T'' and ''81&nbsp;T'' were sent to engage sea traffic across the Strait of Otranto in the area of the Allied naval blockade. Near [[Fasano]],{{sfn|Freivogel|2019|p=235}} they raided the [[Otranto Barrage]],{{sfn|Halpern|1987|p=151}} and ''Orjen'' engaged in a gunnery duel with the British [[Naval drifter|drifter]] ''Beneficent'' then sank her with a torpedo,{{sfn|Freivogel|2019|p=235}} but once the alarm had been raised, the Austro-Hungarian force withdrew.{{sfn|Halpern|1987|p=151}} Only one sailor from ''Beneficent'' survived.{{sfn|Freivogel|2019|p=235}}

The Italian destroyer {{ship|Italian destroyer|Zeffiro|1904|2}}, accompanied by two torpedo boats, entered [[Parenzo]] in Istria on 12 June, covered by two groups of destroyers, with the aim of destroying the seaplane base within the harbour. Coastal batteries and guns at the seaplane station opened fire almost immediately, and three seaplanes took off and began attacking the invaders. In the exchange of fire, ''Zeffiro'' was damaged and the Italians had to retire, pursued by ''93&nbsp;F'', ''98&nbsp;M'' and ''99&nbsp;M''.{{sfn|Freivogel|2019|p=236}} On 3 July, ''83&nbsp;F'', ''85&nbsp;F'', ''87&nbsp;F'' accompanied ''Helgoland'' and three destroyers in a fruitless raid on the Otranto Barrage.{{sfn|Freivogel|2019|p=238}}

On 9 July, ''Novara'' led a force which included ''87&nbsp;F'' and two ''Kaiman''-class torpedo boats in another night raid on the Otranto Barrage which resulted in the sinking of two drifters.{{sfn|Cernuschi|O'Hara|2015|p=170}} The following day, ''75&nbsp;T'' exchanged fire with four enemy warships.{{sfn|Freivogel|2019|p=238}} On 31 July, the Italian submarine {{ship|Italian submarine|Giacinto Pullino||2}} stranded on rocks in the Bay of Fiume. The Austro-Hungarians attempted to salvage her, but she sank while under tow. One of the ships involved in her attempted salvage was ''50&nbsp;E'', which was unsuccessfully attacked by the Italian submarine {{ship|Italian submarine|Argo|1912|2}} during the operation.{{sfn|Freivogel|2019|pp=251–252, 254}} On the night of 1/2 August, the ''Huszár''-class destroyers {{SMS|Warasdiner||2}} and ''Wildfang'' conducted a shore bombardment of [[Molfetta]] on the southern Adriatic coast of Italy, covered by the [[cruiser]] {{SMS|Aspern||2}}, ''80&nbsp;T'' and ''85&nbsp;F''. On the return trip they exchanged fire at extreme range with four Italian destroyers that were trying to intercept them. A further group of Allied vessels led by the Italian [[protected cruiser]] {{ship|Italian cruiser|Nino Bixio||2}} and HMS ''Liverpool'', accompanied by four destroyers and six torpedo boats. The Austro-Hungarian submarine {{SMS|U-4|Austria-Hungary|6|sub=y}} unsuccessfully engaged ''Nino Bixio'', and the Austro-Hungarian force withdrew before the cruisers closed to gun range.{{sfn|Cernuschi|O'Hara|2015|p=171}}{{sfn|Freivogel|2019|p=252}}

''91&nbsp;F'', ''94&nbsp;F'' and ''98&nbsp;M'' were chased and engaged by Italian torpedo boats off Pola on 11 August, resulting in splinter damage to one of the Italian boats.{{sfn|Cernuschi|O'Hara|2015|p=171}} The Austro-Hungarians sent a large force of four cruisers and five destroyers, accompanied by ''83&nbsp;F'', ''85&nbsp;F'', ''87&nbsp;F'' and ''88&nbsp;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.{{sfn|Freivogel|2019|p=255}} On 15 September, in a first in naval warfare, the submerged French submarine {{ship|French submarine|Foucault||2}} was sunk by Austro-Hungarian aircraft near the Bocche. The seaplanes landed and captured the entire crew of 27, holding them until ''100&nbsp;M'' arrived and took them on board. ''87&nbsp;F'', ''99&nbsp;M'' and ''100&nbsp;M'' conducted a fruitless raid on the Otranto Barrage on the night of 4/5 October.{{sfn|Freivogel|2019|pp=255–256}} On 4 November, three Italian destroyers and three torpedo boats were involved in a brief encounter in the northern Adriatic with two Austro-Hungarian destroyers accompanied by ''83&nbsp;F'', ''87&nbsp;F'' and ''88&nbsp;F''.{{sfn|Cernuschi|O'Hara|2015|p=171}} On the following day, ''83&nbsp;F'', ''87&nbsp;F'' and ''88&nbsp;F'' conducted a shore bombardment of [[Sant'Elpidio a Mare]].{{sfn|Cernuschi|O'Hara|2015|p=171}}

====1917====
{{Location map+
| Italy
| AlternativeMap =Italy location map 1905.svg
| float = right
| caption = Map of the Adriatic Sea showing the location of major ports and actions
| width=300
| places =
{{Location map~
| Italy
| label = [[Pula|Pola]]
| label_size = 80
| marksize   = 8
| lat = 44.866667
| long = 13.85
| position = right
| mark = Blue pog.svg
 }}
{{Location map~
| Italy
| label = [[Bocche di Cattaro]]
| label_size = 80
| marksize   = 8
| lat = 42.433333
| long = 18.633333
| position = left
| mark = Blue pog.svg
 }}
{{Location map~
| Italy
| label = [[Strait of Otranto]]
| label_size = 80
| marksize   = 8
| lat = 40.219444
| long = 18.925556
| position = left
| mark = Green pog.svg
 }}
{{Location map~
| Italy
| label = Cortellazzo
| label_size = 80
| marksize   = 8
| lat = 45.53
| long = 12.71
| position = left
| mark = Red pog.svg
 }}
{{Location map~
| Italy
| label = [[Senigallia]]
| label_size = 80
| marksize   = 8
| lat = 43.716667
| long = 13.216667
| position = left
| mark = Red pog.svg
 }}
{{Location map~
| Italy
| label = [[Cesenatico]]
| label_size = 80
| marksize   = 8
| lat = 44.2
| long = 12.394444
| position = left
| mark = Red pog.svg
 }}
}}
At the beginning of 1917, the 1st Torpedo Flotilla, consisting of ''Helgoland'', four ''Tatra''-class destroyers and the 250t-class torpedo boats, was based out of the Bocche.{{sfn|Freivogel|2019|p=296}} During 1917, one of the {{convert|66|mm|in|abbr=on}} guns on each boat was placed on an [[anti-aircraft warfare|anti-aircraft]] mount.{{sfn|Greger|1976|pp=58, 60 & 63}} On the night of 21/22 April, ''84&nbsp;F'', ''92&nbsp;F'', ''94&nbsp;F'' and ''100&nbsp;M'' conducted a night raid on the Otranto Barrage, sinking the freighter ''Japigia''.{{sfn|Freivogel|2019|p=299}}{{efn|According to Cernuschi and O'Hara, the 21/22 April operation also involved four destroyers and sank a drifter.{{sfn|Cernuschi|O'Hara|2016|p=67}} }} On 11 May, the British [[submarine]] {{HMS|H1||2}} stalked ''78&nbsp;T'' off Pola, firing two torpedoes at her. 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&nbsp;T'', allowing her to avoid the incoming torpedoes.{{sfn|Compton-Hall|1991|p=242}} That night, the destroyer ''Csikós'', accompanied by ''78&nbsp;T'', ''93&nbsp;F'' and ''96&nbsp;F'', were pursued in the northern Adriatic by an Italian force of five destroyers, but were able to retire to safety behind a minefield.{{sfn|Cernuschi|O'Hara|2016|p=67}}

On 14–15 May 1917, several 250t-class boats were part of the support forces for a major raid on the Otranto Barrage. When the raiding force departed, torpedo boats and aircraft secured the approaches to the Austro-Hungarian naval base at the Bocche. Once the raiding force had departed for the barrage, ''Sankt Georg'', a destroyer, and ''84&nbsp;F'', ''88&nbsp;F'', ''99&nbsp;M'' and ''100&nbsp;M'' were to be prepared to sortie out to support the raiders on their return voyage. The old [[coastal defence ship]] {{SMS|Budapest||2}} and ''86&nbsp;F'', ''91&nbsp;F'' and ''95&nbsp;F'' were also available at the Bocche if needed. Although the raid was a relative success, sinking 14 drifters, the raiding force was then engaged by Allied ships in the [[Battle of the Otranto Straits]]. Both support groups sailed to meet the returning Austro-Hungarian force, which included the heavily damaged ''Novara'' under tow. On marrying-up with the raiding force, the torpedo boats fanned out to screen the larger warships, protecting them as they returned to port.{{sfn|Cernuschi|O'Hara|2016|p=67}}{{sfn|Halpern|2012|p=162}}{{sfn|Halpern|2004|pp=47, 93–101}} On 21 May 1917, the suffix of all Austro-Hungarian torpedo boats was removed, and thereafter they were referred to only by the numeral.{{sfn|Gardiner|1985|p=339}} On 24 May, ''89'' and the {{sclass|Cobra|torpedo boat|2}} ''16'' were escorting the German minelaying submarines {{SMS|UC-24||2|sub=y}} and {{SMS|UC-74||2}} into the Adriatic from the Bocche when ''UC-24'' was torpedoed and sunk by the {{ship|French submarine|Circé|1907|2|up=yes}}. Only two crew members were rescued.{{sfn|Freivogel|2019|p=319}}

On 3 June, the destroyers ''Wildfang'' and ''Csikós'', along with ''93'' and ''96'', briefly encountered three Italian [[MAS (motorboat)|MAS boats]] off the mouth of the [[Tagliamento]] river in the far north of the Adriatic.{{sfn|Cernuschi|O'Hara|2016|p=67}} This group, with the addition of the destroyer {{SMS|Velebit||2}}, was supporting an attack by six seaplanes on the Italian coast that night when ''Wildfang'' struck a mine about {{cvt|30|nmi}} southwest of Cape Penada on the island of [[Veliki Brijun]] off Istria. She sank in ten minutes, and 25 of the crew drowned, with 74 rescued. 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 (World War I)|Italian front]] in the northern Adriatic which were supported by the Austro-Hungarian fleet. During one of these, an attack on [[Grado, Friuli-Venezia Giulia|Grado]] and [[Cervignano del Friuli]] by 21 aircraft, cover was provided by ''76'', ''80'', ''92'' and ''96'' along with three destroyers.{{sfn|Freivogel|2019|p=320}}

On 23 September, ''77'' and ''78'' were laying a minefield off Grado in the northern Adriatic when they had a brief encounter with an Italian MAS boat.{{sfn|Cernuschi|O'Hara|2016|p=67}} The following night, ''94'', ''95'' and two other torpedo boats again had a short and inconclusive engagement with Italian torpedo boats in the northern Adriatic.{{sfn|Cernuschi|O'Hara|2016|p=67}}{{sfn|Freivogel|2019|p=323}} On 29 September, ''90'', ''94'', ''98'' and ''99'' were accompanying a squadron of four destroyers supporting an air attack on the Italian airfield at [[Ferrara]] by [[flying boat]]s. After destroying an Italian [[airship]], the squadron withdrew at high speed in the darkness, but was intercepted by an Italian squadron of eight destroyers that had been sent from Venice to support an Italian air raid on Pola. In the resultant 45 minute chase towards [[Poreč|Parenzo]], two Italian destroyers and three Austro-Hungarian destroyers were damaged, and ''94'' was hit by splinters. As the squadron retreated through the minefields off Parenzo, ''98'' was also hit by Italian fire, resulting in one casualty.{{sfn|Cernuschi|O'Hara|2016|p=67}}{{sfn|O'Hara|Worth|Dickson|2013|pp=148–149}}{{sfn|Freivogel|2019|p=323}}

Two sorties involving boats of the class were conducted on 18 October. 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 [[Piran]]o destined for the troops on the Italian Front.{{sfn|Freivogel|2019|p=324}}

On 14 November, ''84'', ''92'', ''94'', ''99'' and ''100'' encountered four Italian destroyers off the mouth of the [[Piave (river)|Piave]], but the torpedo boats were again able to elude their pursuers by sailing behind a minefield. Two days later, the coastal defence ships {{SMS|Wien||2}} and ''Budapest'' sailed to engage a {{convert|152|mm|abbr=on|adj=on}} Italian shore battery at Cortellazzo near the mouth of the Piave, with an escort that included ''84'', ''92'', ''94'', ''98''&nbsp;– ''100'' and some [[minesweeper]]s. Both ''Wien'' and ''Budapest'' were hit, but none of the torpedo boats suffered any damage. After an Italian force of seven destroyers and three MAS boats appeared, the bombarding force withdrew.{{sfn|Cernuschi|O'Hara|2016|p=67}} On 28 November, 250t-class boats were involved in two shore bombardment missions. In the first mission, ''79'', ''86'' and ''90'' supported the bombardment of [[Senigallia]] by three destroyers, before they were joined by ''78'', ''82'', ''87'', ''89'' and ''95'' and another three destroyers for the bombardment of Porto Corsini, [[Marotta (village)|Marotta]] and [[Cesenatico]]. On 19 December, a large Austro-Hungarian force engaged the Italian shore battery at Cortellazzo. The force consisted of the pre-dreadnought {{SMS|Árpád||2}}, ''Admiral Spaun'', ''Budapest'', six destroyers, ten torpedo boats including ''84'', ''92'', ''94'' and ''98''&nbsp;– ''100'', and ten minesweepers. None of the ships of the bombarding force suffered damage during the mission.{{sfn|Cernuschi|O'Hara|2016|p=68}}

====1918====
Elements of the Austro-Hungarian fleet [[Cattaro Mutiny|mutinied in the Bocche di Cattaro]] in February 1918,{{sfn|Bell|Elleman|2004|p=51}} and in May, a plot was discovered to take over ''80'' at Pola. The motive appeared to be nationalism. Two of the ringleaders, a [[Czechs|Czech]] and a Dalmatian [[Croats|Croat]], were tried, convicted and executed by firing squad.{{sfn|Bell|Elleman|2004|p=60}}{{sfn|Hathaway|2001|p=204}}{{sfn|Sondhaus|1994|p=334}} On 13 May, the destroyer {{SMS|Dukla||2}}, ''84'' and ''98'' were at Durazzo when two Italian MAS boats forced the harbour, sinking one Austro-Hungarian freighter.{{sfn|Cernuschi|O'Hara|2016|p=68}} On 10 June, ''76''{{spaced ndash}}''79'', ''81'' and ''87'' were part of the escort force that failed to protect the Austro-Hungarian [[dreadnought]] {{ship|SMS|Szent István||2}} from the Italian MAS boats that sank her. During that action, ''76'' fired at the Italian boats, but did not score a hit.{{sfn|Sokol|1968|p=135}}{{sfn|Sieche|1991|pp=127, 131}} On 1 July, the destroyers ''Balaton'' and ''Csikós'', along with ''83'' and ''88'', were chased offshore from [[Caorle]] by seven Italian destroyers. All four Austro-Hungarian ships were hit, with ''83'' hit three times, and ''88'' struck once. One of the Italian destroyers was hit three times, and another was slightly damaged by splinters. On 6 September, ''86'' and two other torpedo boats were engaged by three Italian destroyers in the [[Drin (river)|Gulf of Drin]]. ''86'' was hit, and the Austro-Hungarian force withdrew.{{sfn|Cernuschi|O'Hara|2016|p=69}} On 2 October, ''87'' was at Durazzo when the port was bombarded by a multinational Allied naval force. She escaped with minor damage, in what was the last major action involving the Austro-Hungarian Navy.{{sfn|Cernuschi|O'Hara|2016|p=69}}{{sfn|Halpern|2012|pp=259–261}}

===Post-World War I transfers===
Under the provisions of the [[Treaty of Saint-Germain-en-Laye (1919)|Treaty of Saint-Germain-en-Laye]], all Austro-Hungarian warships were surrendered to the Allies. The 250t-class torpedo boats were distributed among [[Kingdom of Romania|Romania]], [[First Portuguese Republic|Portugal]], [[Kingdom of Greece|Greece]], and the newly created [[Kingdom of Yugoslavia|Kingdom of Serbs, Croats and Slovenes]] (later Yugoslavia), as follows:{{sfn|Greger|1976|pp=58, 60 & 63}}

{|class="wikitable sortable" style="text-align: center;"
|+ Transfer of T-group torpedo boats{{sfn|Greger|1976|p=58}}
|-
! scope="col" | Austro-Hungarian name
! scope="col" | Transferred to
! scope="col" | New name
! scope="col" class="unsortable" | Inter-war fate
|-
! scope="row" | ''74''
| {{navy|Kingdom of Romania|name=Romanian Navy}} || ''Viforul'' || scrapped in 1932
|-
! scope="row" | ''75''
| {{flagicon|Kingdom of Romania|naval Romanian Navy}} || ''Vartejul'' || scrapped in 1932
|-
! scope="row" | ''76''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the [[Kingdom of Serbs, Croats and Slovenes]] || ''T1'' ||
|-
! scope="row" | ''77''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T2'' || scrapped in 1939
|-
! scope="row" | ''78''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T3'' ||
|-
! scope="row" | ''79''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T4'' || lost 1932{{efn|''T4'' ran aground on the Dalmatian coast and became a total loss.{{sfn|Greger|1976|p=58}}}}
|-
! scope="row" | ''80''
| {{flagicon|Kingdom of Romania|naval Romanian Navy}} || ''Vijelia'' || scrapped in 1932
|-
! scope="row" | ''81''
| {{flagicon|Kingdom of Romania|naval Romanian Navy}} || ''Sborul'' ||
|}

{|class="wikitable sortable" style="text-align: center;"
|+ Transfer of F-group torpedo boats{{sfn|Greger|1976|p=60}}
|-
! scope="col" | Austro-Hungarian name
! scope="col" | Transferred to
! scope="col" | New name
! scope="col" class="unsortable" | Inter-war fate
|-
! scope="row" | ''82''
| {{flagicon|Kingdom of Romania|naval}} Romanian Navy || ''Năluca'' ||
|-
! scope="row" | ''83''
| {{flagicon|Kingdom of Romania|naval}} Romanian Navy || ''Smeul'' ||
|-
! scope="row" | ''84''
| {{flagicon|Kingdom of Romania|naval}} Romanian Navy || ''Fulgerul'' || lost in the [[Bosphorus]]{{efn|En route to the Black Sea after handover.{{sfn|Greger|1976|p=60}}}}
|-
! scope="row" | ''85''
| {{navy|Portugal}} || ''Zezere'' || lost 1921{{efn|Wrecked near [[Bône, Algeria]], while en route from the Adriatic to Portugal after handover.{{sfn|Greger|1976|p=60}}}}
|-
! scope="row" | ''86''
| [[File:Flag of Portugal.svg|22px]] Portuguese Navy || ''Ave'' || scrapped 1940
|-
! scope="row" | ''87''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T5'' ||
|-
! scope="row" | ''88''
| [[File:Flag of Portugal.svg|22px]] Portuguese Navy || ''Cavado'' || lost 1921{{efn|Wrecked near [[Bône, Algeria]], while en route from the Adriatic to Portugal after handover.{{sfn|Greger|1976|p=60}}}}
|-
! scope="row" | ''89''
| [[File:Flag of Portugal.svg|22px]] Portuguese Navy || ''Sado'' || scrapped 1940
|-
! scope="row" | ''90''
| [[File:Flag of Portugal.svg|22px]] Portuguese Navy || ''Liz'' || scrapped 1934
|-
! scope="row" | ''91''
| [[File:Flag of Portugal.svg|22px]] Portuguese Navy || ''Mondego'' || scrapped 1938
|-
! scope="row" | ''92''
| {{navy|Greece|royalnavy}} || ''Proussa'' ||
|-
! scope="row" | ''93''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T6'' ||
|-
! scope="row" | ''94''
| [[File:Flag of Greece.svg|22px]] Hellenic Navy || ''Panormos'' || lost 1938{{efn|Struck a reef and sank off the island of [[Aegina]].{{sfn|Greger|1976|p=60}}}}
|-
! scope="row" | ''95''
| [[File:Flag of Greece.svg|22px]] Hellenic Navy || ''Pergamos'' ||
|-
! scope="row" | ''96''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T7'' ||
|-
! scope="row" | ''97''
| [[File:Flag of the Kingdom of Yugoslavia.svg|22px]] Navy of the Kingdom of Serbs, Croats and Slovenes || ''T8'' ||
|}

{|class="wikitable sortable" style="text-align: center;"
|+ Transfer of M-group torpedo boats{{sfn|Greger|1976|p=63}}
|-
! scope="col" | Austro-Hungarian name
! scope="col" | Transferred to
! scope="col" | New name
! scope="col" class="unsortable" | Inter-war fate
|-
! scope="row" | ''98''
| [[File:Flag of Greece.svg|22px]] Hellenic Navy || ''Kyzikos'' ||
|-
! scope="row" | ''99''
| [[File:Flag of Greece.svg|22px]] Hellenic Navy || ''Kios'' ||
|-
! scope="row" | ''100''
| [[File:Flag of Greece.svg|22px]] Hellenic Navy || ''Kydoniai'' ||
|}

===World War II===
[[File:Yugoslav torpedo boat T3.jpg|thumb|upright=1.38|The Yugoslav torpedo boat ''T3'' photographed in 1931|alt=a black and white image of a ship underway]]
By 1940, thirteen boats of the class had been lost or scrapped, including all six Portuguese boats.{{sfn|Greger|1976|pp=58, 60 & 63}} At the time of the [[Axis powers|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.{{sfn|Niehorster|2013a}} ''T5''–''T8'' comprised the 3rd Torpedo Division located at [[Šibenik]].{{sfn|Niehorster|2013b}} On 8 April, the four boats of the 3rd Torpedo Division, along with other vessels, were tasked to support an attack on the Italian enclave of [[Province of Zara|Zara]] on the Dalmatian coast. They were subjected to three Italian air attacks and, after the last one, sailed from the area of [[Zaton, Zadar County|Zaton]] into [[Lake Prokljan]], where they remained until 11 April.{{sfn|Terzić|1982|p=333}} On 12 April, the 3rd Torpedo Division arrived at [[Milna]] on the island of [[Brač]], and refused to follow orders to sail to the Bay of Kotor.{{sfn|Terzić|1982|p=404}} All six Yugoslav boats were then captured by the Italians.{{sfn|Greger|1976|pp=58 & 60}}

The five surviving Greek boats were all sunk by aircraft during the [[Battle of Greece|German invasion of Greece]], also in April 1941. The first was ''Proussa'', which was sunk off Corfu on 4 April by Italian [[Junkers Ju 87]] "Picchiatellos" of the 239th Squadron, 97th Dive Bomber Group.{{sfn|Weal|1998|p=22}}{{efn|According to Greger, ''Proussa'' was sunk by German bombers on the same day and at the same location.{{sfn|Greger|1976|p=63}}}} Later, ''Kios'' was sunk off [[Athens]] on 22 April, ''Kyzikos'' at [[Salamis Naval Base|Salamis]] on 24 April, ''Pergamos'' off Salamis on 25 April, and ''Kydoniai'' south of the [[Peloponnese]] peninsula on the following day, all by German aircraft.{{sfn|Greger|1976|p=63}}

The three Romanian boats were initially deployed against the [[Soviet Navy]] [[Black Sea Fleet]] following the launch of [[Operation Barbarossa]] in June 1941.{{sfn|Greger|1976|pp=58, 60 & 63}} ''[[NMS Năluca|Năluca]]'' took part in the [[action of 9 July 1941|sinking of one Soviet submarine]] near [[Mangalia]] on 9 July 1941,{{sfn|Preston|2001|p=72}}{{sfn|Crăciunoiu|2003|p=135}}{{sfn|Rotaru|Damaschin|2000|pp=34, 50–51}} but was herself sunk by Soviet aircraft at [[Constanța]] on 20 August 1944. ''[[NMS Sborul|Sborul]]'' and ''[[NMS Smeul|Smeul]]'' survived World War II,{{sfn|Greger|1976|pp=58 & 60}} 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.{{sfn|Monakov|Rohwer|2001|pp=167 & 171}}

The Yugoslav boats served in a coastal and second-line escort role with the [[Regia Marina|Royal Italian Navy]] ({{langx|it|Regia Marina}}) in the Adriatic under their Yugoslav designations, and were fitted with two {{convert|76|mm|in|abbr=on}} L/30 anti-aircraft guns in place of their 66&nbsp;mm guns,{{sfn|Brescia|2012|p=151}} but no other significant alterations were made to them.{{sfn|Chesneau|1980|p=304}} After the Italians [[Armistice of Cassibile|capitulated]] in September 1943, they transferred ''T1'' back to the KJRM-in-exile in December of that year.{{efn|One source states that she was captured by the Germans and transferred to the [[Navy of the Independent State of Croatia|navy]] of the puppet state, the [[Independent State of Croatia]] (NDH),{{sfn|Gardiner|1985|p=339}} but several other sources state that she was returned to the KJRM in December 1943.{{sfn|Brescia|2012|p=151}}{{sfn|Chesneau|1980|p=357}}{{sfn|Whitley|1988|p=186}}}} ''T3'' was seized by the Germans at Rijeka on 16 September 1943 and was renamed ''TA48''. She was commissioned on 15 August 1944, and was used for patrol and escort work in the northern Adriatic.{{sfn|Whitley|1988|p=81}} The Germans added to her armament, fitting her with two single {{convert|20|mm|in|abbr=on}} anti-aircraft guns in addition to the guns fitted by the Italians, and removing two of her torpedo tubes.{{sfn|Lenton|1975|p=107}} There are two versions of how ''TA48'' was employed. The first version indicates that she was crewed exclusively by Croatian officers and sailors, but remained under German control,{{sfn|Gardiner|1985|p=339}} and the second states that she was handed over to the Navy of the Independent State of Croatia, but was repossessed by the Germans on 14 December 1944 because they considered the Croatians unreliable.{{sfn|Whitley|1988|p=81}} Her complement was also increased to 52 during her German-Croatian service.{{sfn|Gardiner|1985|p=339}} She was sunk in the port of Trieste by [[Allies of World War II|Allied]] aircraft on 20 February 1945.{{sfn|Gardiner|1985|p=339}}{{sfn|Chesneau|1980|p=357}}{{efn|Sources conflict on who sank ''TA48''. Gardiner and Lenton state that they were Allied aircraft without specifying their nationality,{{sfn|Gardiner|1985|p=339}}{{sfn|Lenton|1975|p=110}} while Chesneau states they were British aircraft,{{sfn|Chesneau|1980|p=357}} and Wilmott states that US aircraft carried out the attack.{{sfn|Willmott|2010|p=209}}}}

''T5'' was also returned to the KJRM-in-exile in December 1943.{{sfn|Gardiner|1985|p=339}} ''T6'' was scuttled by the Italians {{convert|30|km|abbr=on}} north of Rimini on 11 September as she had insufficient fuel on board to reach an Allied port.{{sfn|Brown|1995|p=92}} Once under German control, ''T7'' was also handed over to the Navy of the Independent State of Croatia, and served under her Yugoslav designation. Her crew came under the influence of [[Yugoslav Partisans|Yugoslav Partisan]] propaganda, and were preparing to mutiny when the Germans intervened.{{sfn|Gardiner|1985|p=339}}{{sfn|Chesneau|1980|p=357}} On 24 June 1944, she and the [[E-boat|S-boats]] ''S 154'' and ''S 157'' of the 7th S-Boat Flotilla were sailing between Šibenik and Rijeka, protecting German sea supply routes along the Adriatic, when they were attacked by the [[Royal Navy]] [[Fairmile D motor torpedo boat]]s ''MTB 659'', ''MTB 662'' and ''MTB 670'' near the island of Kukuljari, south of [[Murter|Murter Island]]. The MTBs fired two torpedoes at ''T7'', but missed, so they closed and engaged her with their guns, setting her ablaze. She was beached, and 21 crew were rescued by the MTBs. The British crews later examined the wreck, capturing five more crew, then destroyed her with demolition charges.{{sfn|Paterson|2015|p=223}} ''T8'' was sunk {{convert|37|km|abbr=on}} north-west of [[Dubrovnik]] by German aircraft while evacuating Italian troops from Dalmatia on 10 or 11 September 1943.{{sfn|Gardiner|1985|p=339}}{{sfn|Chesneau|1980|p=357}}{{sfn|Whitley|1988|p=186}}{{sfn|Brown|1995|p=92}}

===Post-World War II===
Only four of the twenty-seven 250t-class torpedo boats survived World War II, two in Yugoslav service and two in Soviet service. ''T1'' was commissioned by the [[Yugoslav Navy]] after the war as ''Golešnica''.{{sfn|Chesneau|1980|p=357}} She was re-armed with two {{convert|40|mm|in|abbr=on}} guns on single mounts and four {{convert|20|mm|in|abbr=on}} guns, and her torpedo tubes were removed. She continued in Yugoslav service under that name until October 1959. ''T5'' was also commissioned by the Yugoslav Navy after the war,{{sfn|Chesneau|1980|p=357}} and renamed ''Cer''. She was fitted with two {{convert|40|mm|in|abbr=on}} guns on single mounts and one {{convert|20|mm|in|abbr=on}} gun, and her torpedo tubes were also removed. She served until 1962, when she was broken up.{{sfn|Gardiner|1983|p=388}} ''Musson'' and ''Toros'' were returned to Romania in October 1945, and stricken the following month.{{sfn|Monakov|Rohwer|2001|p=270}}{{efn|According to Greger, ''Toros'' survived the war and was scrapped in 1960.{{sfn|Greger|1976|p=60}}}}

==Notes==
{{reflist|group=lower-alpha}}

==Footnotes==
{{reflist|20em}}

==References==

===Books===
{{refbegin|40em}}
* {{cite book
  | last1 = Bell
  | first1 = Christopher
  | last2 = Elleman
  | first2 = Bruce
  | year = 2004
  | title = Naval Mutinies of the Twentieth Century: An International Perspective
  | publisher = Routledge
  | location = London, England
  | isbn = 978-1-135-75553-9
  | url = https://books.google.com/books?id=2kaRAgAAQBAJ
  }}
* {{cite book
  | last = Brescia
  | first = Maurizio
  | year = 2012
  | title = Mussolini's Navy
  | publisher = Seaforth Publishing
  | location = Barnsley, South Yorkshire
  | isbn = 978-1-59114-544-8
  }}
* {{cite book
  | last = Brown
  | first = David
  | title = Warship Losses of World War Two
  | year = 1995
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-1-55750-914-7
  }}
* {{cite book
  | last1 = Cernuschi
  | first1 = Enrico
  | last2 = O'Hara
  | first2 = Vincent P.
  | editor-last = Tucker
  | editor-first = Spencer C.
  | year = 2014
  | title = World War I: The Definitive Encyclopedia and Document Collection
  | chapter = Action off Pelagosa
  | publisher = ABC-CLIO
  | location = Santa Barbara, California
  | isbn = 978-1-85109-965-8
  | url = https://books.google.com/books?id=DBwTBQAAQBAJ
  | name-list-style = amp
  }}
* {{cite book
  | last1 = Cernuschi
  | first1 = Enrico
  | last2 = O'Hara
  | first2 = Vincent P.
  | editor-last = Jordan
  | editor-first =John
  | title = Warship 2015
  | publisher = Bloomsbury
  | location = London, England
  | year = 2015
  | pages = 161–173
  | chapter = The Naval War in the Adriatic Part I: 1914–1916
  | isbn = 978-1-84486-295-5
  | name-list-style = amp
  }}
* {{cite book
  | last1 = Cernuschi
  | first1 = Enrico
  | last2 = O'Hara
  | first2 = Vincent P.
  | editor-last = Jordan
  | editor-first =John
  | title = Warship 2016
  | publisher = Bloomsbury
  | location = London, England
  | year = 2016
  | pages = 62–75
  | chapter = The Naval War in the Adriatic Part II: 1917–1918
  | isbn = 978-1-84486-438-6
  | name-list-style = amp
  }}
* {{cite book
  | editor-last = Chesneau
  | editor-first = Roger
  | year = 1980
  | title = Conway's All the World's Fighting Ships 1922–1946
  | publisher = Conway Maritime Press
  | location = London, England
  | isbn = 978-0-85177-146-5
  }}
* {{cite book
  | last = Compton-Hall
  | first = Richard
  | title = Submarines and the War at Sea, 1914–18
  | year = 1991
  | publisher = Macmillan
  | location = London, England
  | isbn = 978-0-333-44345-3
  }}
* {{cite book
  | last = Crăciunoiu
  | first = Cristian
  | title = Romanian Navy Torpedo Boats
  | year = 2003
  | publisher = Modelism
  | location = Bucharest, Romania
  | isbn = 978-973-8101-17-3
  }}
*{{cite book |last1=Freivogel |first1=Zvonimir |title=The Great War in the Adriatic Sea 1914–1918 |date=2019 |publisher=Despot Infinitus |location=Zagreb, Croatia |isbn=978-953-8218-40-8}}
* {{cite book |last=Freivogel|first=Zvonimir |author-link= |year=2020 |title=Warships of the Royal Yugoslav Navy 1918–1945|volume=1 |url= |location=Zagreb, Croatia |publisher=Despot Infinitus|isbn=978-953-8218-72-9}}
*{{cite book |last1=Freivogel |first1=Zvonimir |title=Austro-Hungarian Torpedo-Boats in World War One |date=2022 |publisher=Despot Infinitus |location=Zagreb, Croatia |isbn=((978-953-366-036-9))}}
* {{cite book
  | last = Friedman
  | first = Norman
  | author-link = Norman Friedman
  | year = 2011
  | title = Naval Weapons of World War One
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-1-84832-100-7
  }}
* {{cite book
  | editor-last = Gardiner
  | editor-first = Robert
  | year = 1985
  | title = Conway's All the World's Fighting Ships 1906–1921
  | publisher = Conway Maritime Press
  | location = London, England
  | isbn = 978-0-85177-245-5
  }}
* {{cite book
  | editor-last = Gardiner
  | editor-first = Robert
  | year = 1983
  | title = Conway's All the World's Fighting Ships 1947–1982
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-0-87021-919-1
  | url-access = registration
  | url = https://archive.org/details/conwaysallworlds0000unse
  }}
* {{cite book
  | last = Greger
  | first = René
  | year = 1976
  | title = Austro-Hungarian Warships of World War I
  | publisher = Ian Allan
  | location = London, England
  | isbn = 978-0-7110-0623-2
  }}
* {{cite book
  | editor-last = Halpern
  | editor-first = Paul G.
  | year = 1987
  | title = The Royal Navy in the Mediterranean, 1915–1918
  | publisher = Temple Smith, Gower Publishing Company
  | location = Aldershot, England
  | isbn = 978-0-566-05488-4
  }}
* {{cite book
  | last = Halpern
  | first = Paul G.
  | year = 2004
  | title = The Battle of the Otranto Straits: Controlling the Gateway to the Adriatic in World War I
  | publisher = Indiana University Press
  | location = Bloomington, Indiana
  | isbn =978-0-253-11019-0
  }}
* {{cite book
  | last = Halpern
  | first = Paul G.
  | year = 2012
  | title = A Naval History of World War I
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-0-87021-266-6
  }}
* {{cite book
  | last = Hathaway
  | first = Jane
  | year = 2001
  | title = Rebellion, Repression, Reinvention: Mutiny in Comparative Perspective
  | publisher = Praeger
  | location = Westport, Connecticut
  | isbn = 978-0-275-97010-9
  | url = https://books.google.com/books?id=6dLGTvbWiT0C
}}
* {{cite book
  | last = Jane's Information Group
  | year = 1989
  | orig-year = 1946/47
  | title = Jane's Fighting Ships of World War II
  | publisher = Studio Editions
  | location = London, England
  | isbn = 978-1-85170-194-0
  }}
* {{cite book
  | last = Lenton
  | first = H.T.
  | year = 1975
  | title = German Warships of the Second World War
  | publisher = Macdonald and Jane's
  | location = London, England
  | isbn = 978-0-356-04661-7
  }}
* {{cite book
  | last1 = Monakov
  | first1 = Mikhail
  | last2 = Rohwer
  | first2 = Jurgen
  | year = 2001
  | title = Stalin's Ocean-going Fleet: Soviet Naval Strategy and Shipbuilding Programs, 1935–53
  | publisher = Frank Cass
  | location = Portland, Oregon
  | isbn = 978-1-136-32191-7
  | url = https://books.google.com/books?id=eEQsBgAAQBAJ
  }}
* {{cite book
  | last1 = O'Hara
  | first1 = Vincent
  | last2 = Worth
  | first2 = Richard
  | last3 = Dickson
  | first3 = W.
  | year = 2013
  | title = To Crown the Waves: The Great Navies of the First World War
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-1-61251-269-3
  | url = https://books.google.com/books?id=2RlFAAAAQBAJ
  | name-list-style = amp
  }}
* {{cite book
  | last = Paterson
  | first = Lawrence
  | title = Schnellboote: A Complete Operational History
  | url = https://books.google.com/books?id=w34ACwAAQBAJ
  | year = 2015
  | publisher = Seaforth Publishing
  | location = Barnsley, England
  | isbn = 978-1-84832-083-3
  }}
* {{cite book
  | last = Preston
  | first = Antony
  | title = Warship 2001–2002
  | year = 2001
  | publisher = Conway Maritime
  | location = London, England
  | isbn = 978-0-85177-901-0
  }}
* {{cite book
  | last1 = Rotaru
  | first1 = Jipa
  | last2 = Damaschin
  | first2 = Ioan
  | title = Glorie și dramă: Marina Regală Română, 1940–1945
  | trans-title = Glory and Drama: The Royal Romanian Navy, 1940–1945
  | language = ro
  | year = 2000
  | publisher = Editura "Ion Cristoiu"
  | location = Bucharest, Romania
  | isbn = 978-973-99544-7-1
  }}
* {{cite journal
  | last = Sieche
  | first = Erwin F.
  | year = 1991
  | title = S.M.S. Szent István: Hungaria's Only and Ill-Fated Dreadnought
  | journal = Warship International
  | publisher = International Warship Research Organization
  | location = Toledo, Ohio
  | volume = XXVII
  | issue = 2
  | pages = 112–146
  | issn = 0043-0374
  }}
* {{cite book
  | last = Sokol
  | first = Anthony Eugene
  | year = 1968
  | title = The Imperial and Royal Austro-Hungarian Navy
  | publisher = U.S. Naval Institute
  | location = Annapolis, Maryland
  | isbn = 9780870212925
 | oclc = 1912
  | url = https://books.google.com/books?id=hoUgAAAAMAAJ
}}
* {{cite book
  | last = Sondhaus
  | first = Lawrence
  | year = 1994
  | title = The Naval Policy of Austria-Hungary, 1867–1918: Navalism, Industrial Development, and the Politics of Dualism
  | publisher = Purdue University Press
  | location = West Lafayette, Indiana
  | isbn = 978-1-55753-034-9
  | url = https://books.google.com/books?id=O8xHL01QG8cC&pg=PA334
  }}
* {{cite book
  | last = Terzić
  | first = Velimir
  | year = 1982
  | title = Slom Kraljevine Jugoslavije 1941: Uzroci i posledice poraza
  |trans-title=The Collapse of the Kingdom of Yugoslavia in 1941: Causes and Consequences of Defeat
  | language = sh
  | volume = 2
  | publisher = Narodna knjiga
  | location = Belgrade, Yugoslavia
  | oclc = 10276738
  }}
* {{cite book
  | last = Weal
  | first = John
  | year = 1998
  | title = Junkers Ju 87 Stukageschwader of North Africa and the Mediterranean
  | publisher = Osprey
  | location = Oxford, England
  | isbn = 978-1-85532-722-1
  | url = https://books.google.com/books?id=8LwbMT2lrwAC
  }}
* {{cite book
  | last = Whitley
  | first = M. J.
  | title = Destroyers of World War Two: An International Encyclopedia
  | url = https://books.google.com/books?id=u4XfAAAAMAAJ
  | year = 1988
  | publisher = Naval Institute Press
  | location = Annapolis, Maryland
  | isbn = 978-0-87021-326-7
  }}
* {{cite book
  | last = Willmott
  | first = H. P.
  | title = The Last Century of Sea Power: From Washington to Tokyo, 1922–1945
  | url = https://books.google.com/books?id=2AiIL5icXqMC
  | year = 2010
  | publisher = Indiana University Press
  | location = Bloomington, Indiana
  | isbn = 978-0-253-35214-9
  }}
{{refend}}

===Websites===
{{refbegin|40em}}
* {{cite web
| work = World War II Armed Forces: Orders of Battle and Organizations
| url =  http://www.niehorster.org/040_yugoslavia/41-04-06/navy_coast.html
| title = Balkan Operations Order of Battle Royal Yugoslavian Navy Coastal Defense Command 6th April 1941
| access-date = 18 April 2015
| year   = 2013a
| last = Niehorster
| first = Leo
}}
* {{cite web
| work = World War II Armed Forces: Orders of Battle and Organizations
| url =  http://www.niehorster.org/040_yugoslavia/41-04-06/navy.html
| title = Balkan Operations Order of Battle Royal Yugoslavian Navy 6th April 1941
| access-date = 18 April 2015
| year   = 2013b
| last = Niehorster
| first = Leo
}}
{{refend}}

{{Austro-Hungarian Navy classes}}
{{Ships of the Royal Yugoslav Navy}}

{{DEFAULTSORT:Vardar}}
[[Category:Ships built in Trieste]]
[[Category:Naval ships of Yugoslavia captured by Germany during World War II]]
[[Category:Naval ships of Yugoslavia captured by Italy during World War II]]
[[Category:Torpedo boats of the Regia Marina]]
[[Category:Torpedo boats of the Royal Yugoslav Navy]]
[[Category:Torpedo boats of the Soviet Navy]]
[[Category:Torpedo boats of the Kriegsmarine]]
[[Category:World War I torpedo boats of Austria-Hungary]]
[[Category:World War II torpedo boats of Romania]]
[[Category:Ships built in Fiume]]
[[Category:Ships built in Croatia]]