# Pegaso-class torpedo boat

Class overview :
| Builders | Pattison, Naples, Odero, Sestri Ponente |
| Operators | Regia Marina |
| Preceded by | Sirio class |
| Succeeded by | Orione class |
| Built | 1904–1909 |
| In commission | 1905–1927 |
| Completed | 18 |
| Lost | 2 |
| Retired | 16 |
| General characteristics ||
| Type | High-Seas Torpedo boat |
| Displacement | 210 t (210 long tons) (Perseo series) 216.5 t (213.1 long tons) (Cigno and Alcione series) |
| Length | 50.05 m (164 ft 2 in) pp 50.35 m (165 ft 2 in) oa |
| Beam | 5.3 m (17 ft 5 in) |
| Draught | 1.725–1.775 m (5 ft 7.9 in – 5 ft 9.9 in) |
| Propulsion | 2 × Vertical triple-expansion steam engines Coal-fired Thornycroft boilers 2,900 ihp (2,200 kW) |
| Speed | 25 kn (46 km/h; 29 mph) |
| Range | 300–350 nmi (350–400 mi; 560–650 km) at full speed |
| Complement | 3 officer + 32–39 men |
| Armament | 2× 57 mm/43 guns 1× 47 mm/43 gun 3× 450 mm (17.7 in) torpedo tubes |
The Pegaso class was a class of 18 Italian sea-going steam-powered torpedo boats built between 1904 and 1909. They served in the Italo-Turkish War and the First World War, when one was sunk, and continued in use until the 1920s.

## Design

In 1904, four High-Seas Torpedo Boats were laid down at the Pattison shipyard of Naples, to a design licensed from the British shipbuilder Thornycroft. They were powered by two triple expansion steam engines fed by two Thornycroft coal-fired water-tube boilers which gave 2,900–3,279 ihp (2,163–2,445 kW) driving two shafts and allowing the contract speed of 25 knots (46 km/h; 29 mph) to be reached. Two funnels were fitted. Torpedo armament consisted of three 450 mm (17.7 in) torpedo tubes, with a gun armament of two 57 mm/43 guns and one 47 mm/43 gun.
While these four ships (known as the Perseo series) were built, launching and completing in 1905–06, work began on two further batches, with eight more being ordered from Pattison (the Cigno series) and six from Odero, Sestri (the Alcione series). These ships were built with thicker plating than those of the Perseo series, and so were slightly heavier (displacing 216.5 t (213.1 long tons) compared with 210 t (210 long tons) for the earlier ships). Two of the Cignos, Calipso and Climene were fitted with oil fired boilers during construction, while six more ships (Pallade, Pegaso, Procione, Airone, Alcione and Ardea) were converted to oil fuel between 1908 and 1913.
The ships were re-armed during the First World War, with the Perseo and Cigno series replacing their armament with two 76 mm (3 in)/40 guns, one 13.2 mm machine gun and two 450 mm torpedo tubes. The Alcione series' new armament differed in that one of the 76 mm guns was an anti-aircraft gun.

## Service

In September 1911, the Italo-Turkish War broke out. The Italian Navy, including its torpedo boats, was highly active during the war. Actions involving the Pegaso class included Cigno carrying out shore bombardment along with larger units of the fleet in support of Italian land forces near Tripoli in November 1911, and a reconnaissance of the Dardanelles by five torpedo boats (the Sirio-class ship Spica and four Pegaso-class ships, Perseo, Astore, Climene and Centauro).
Several of the Pegaso class were used as high-speed minesweepers during the First World War. Perseo collided with sister ship Astore on 6 February 1917, and sunk when one of its torpedoes exploded. Arpia struck the wreck of the Neapolitan frigate Torquato Tasso (which had sunk off Porto d'Ascoli in 1861) on 17 January 1918. It sustained major damage and sank in shallow water, but was raised and repaired, re-entering service in July 1918.
The surviving vessels were discarded from 1923 to 1927.

## Ships
### Perseo series

Construction data (Perseo series) :
| Ship | Builder | Laid down | Launched | Completed | Operational history |
| Perseo | Pattison, Naples | 10 August 1904 | 5 December 1905 | 26 August 1906 | Sank 6 February 1917 following collision with torpedo boat Astore off Stromboli |
| Pegaso | Pattison, Naples | 13 August 1904 | 12 August 1905 | 23 September 1906 | Discarded 4 March 1923 |
| Procione | Pattison, Naples | 23 August 1904 | 16 December 1905 | 26 September 1906 | Converted to minesweeper 1917; Discarded 17 April 1923 |
| Pallade | Pattison, Naples | 25 August 1904 | 1 June 1906 | 26 September 1906 | Discarded 4 March 1923 |

### Cigno series

Construction data (Cigno series) :
| Ship | Builder | Laid down | Launched | Completed | Operational history |
| Cigno | Pattison, Naples | 17 April 1905 | 9 May 1906 | 26 September 1906 | Discarded 4 March 1923 |
| Cassiopea | Pattison, Naples | 28 April 1905 | 7 July 1906 | 26 September 1906 | Minesweeper 1917–18; Discarded 27 November 1927 |
| Centauro | Pattison, Naples | 21 June 1905 | 20 December 1906 | 26 May 1907 | Ran aground off Antalya, Turkey 5 November 1921 and sank |
| Clio | Pattison, Naples | 27 July 1905 | 20 October 1906 | 17 April 1907 | Discarded 4 March 1923 |
| Canopo | Pattison, Naples | 22 August 1905 | 28 February 1907 | 22 June 1907 | Discarded 4 March 1923 |
| Calliope | Pattison, Naples | 28 September 1905 | 7 August 1906 | 22 December 1906 | Discarded 13 November 1924 |
| Calipso | Pattison, Naples | January 1908 | 26 April 1909 | 16 July 1909 | Discarded 1 September 1927 |
| Climene | Pattison, Naples | January 1908 | 15 May 1909 | 16 August 1909 | Discarded 25 July 1927 |

### Alcione series

Construction data (Alcione series) :
| Ship | Builder | Laid down | Launched | Completed | Operational history |
| Alcione | Odero, Sestri | 18 August 1905 | 13 September 1906 | 1 August 1907 | Minesweeper 1917; Discarded 4 March 1923 |
| Ardea | Odero, Sestri | 18 August 1905 | 10 January 1907 | 23 May 1907 | Discarded 4 March 1923 |
| Albatros | Odero, Sestri | 18 August 1905 | 22 January 1907 | 14 August 1907 | Discarded 4 March 1923 |
| Airone | Odero, Sestri | 19 April 1906 | 13 May 1907 | 28 November 1907 | Minesweeper 1918; Sank Austro-Hungarian submarine U-23 in Strait of Otranto using explosive paravane, 21 February 1918; Discarded 25 September 1923 |
| Astore | Odero, Sestri | 19 April 1906 | 22 June 1907 | 27 January 1908 | Discarded 14 June 1923 |
| Arpia | Odero, Sestri | 8 June 1906 | 22 August 1907 | 25 April 1908 | Struck wreckage off Porto d'Ascoli and sunk 17 January 1918; Salvaged and repaired, recommissioned 25 July 1918; Discarded 15 March 1923 |