The ''O'Byrne''-class submarines were a class of three submarines built for the

French Navy The French Navy (french: Marine nationale, lit=National Navy), informally , is the maritime arm of the French Armed Forces and one of the five military service branches of France. It is among the largest and most powerful naval forces in t ...

from 1917 to 1921. They were originally ordered by the Romanian Navy, but were confiscated by the French government while still under construction. Three ships of the type were built between 1917 and 1921 at the Schneider shipyard in

Chalon-sur-Saône Chalon-sur-Saône (, literally ''Chalon on Saône'') is a city in the Saône-et-Loire department in the region of Bourgogne-Franche-Comté in eastern France. It is a sub-prefecture of the department. It is the largest city in the department; h ...

. They were commissioned in the French Navy, serving in the Mediterranean Sea. The ships were removed from the Navy list between 1928 and 1935. The first ship of its class was named in honour of French submariner Gabriel O'Byrne.

Construction and specifications

''O'Byrne'' and her two

sister ship A sister ship is a ship of the same class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They often share a ...

s (''Henri Fournier'' and ''Louis Dupetit-Thouars'') were ordered by the Romanian Government from the Schneider Shipyard in Chalon-sur-Saône, being

laid down Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship. Keel laying is one o ...

in April 1917. However France seized the submarines for its navy during

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

. The three submarines were subsequently completed for the French Navy, with larger bridges and conning towers. ''O'Byrne'' was the first to be launched (22 May 1919), followed by ''Henri Fournier'' (30 September 1919) and ''Louis Dupetit-Thouars'' (12 May 1920). They were completed and commissioned in 1921. Each of the three submarines had a surfaced displacement of 342 tons, measuring in length, with a

beam Beam may refer to: Streams of particles or energy *Light beam, or beam of light, a directional projection of light energy **Laser beam *Particle beam, a stream of charged or neutral particles **Charged particle beam, a spatially localized grou ...

of and a draught of . The power plant consisted of two Schneider diesel engines and two electric motors powering two shafts, resulting in a surfaced top speed of . Each vessel had a range of at and a crew of 25. Armament consisted of four 450 mm

torpedo tube A torpedo tube is a cylindrical device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units (also referred to as torpedo launchers) installed aboa ...

s and one 47 mm deck gun.Paul E. Fontenoy, ''Submarines: An Illustrated History of Their Impact'', ABC-CLIO Publishing, 2007 p. 89Bernard Fitzsimons, ''The Illustrated encyclopedia of 20th century weapons and warfare, Volume 19'', Columbia House, 1978, p. 2037

Service

The three boats incorporated lessons from the French war experience, and thus proved to be reasonably successful. They served in the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...

after World War I, but their careers were uneventful, and they were taken out of service before the start of World War II. ''Louis Dupetit-Thouars'' was stricken in November 1928 and her two sister ships in August 1935. The ''O'Byrne''-class submarines were originally ordered by the Romanian Navy, but were confiscated by the French government while still under construction. Had ''O'Byrne'' been delivered to Romania upon completion, she would have become the first Romanian submarine. This role would be fulfilled by the Italian-built in 1936.

Ships

References

{{DEFAULTSORT:O'Byrne Submarines of the French Navy Ship classes of the French Navy