''O'Byrne'' was a submarine of the

French Navy The French Navy (, , ), informally (, ), is the Navy, maritime arm of the French Armed Forces and one of the four military service branches of History of France, France. It is among the largest and most powerful List of navies, naval forces i ...

, the

lead ship The lead ship, name ship, or class leader is the first of a series or class of ships that are all constructed according to the same general design. The term is applicable to naval ships and large civilian vessels. Large ships are very comple ...

of her class. She was ordered by Romania during

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

and

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 ...

in April 1917 at the Schneider Shipyard in Gironde. However, she was requisitioned by French authorities at the end of the year and completed for the French Naval Forces. Upon commissioning in 1921, she became the first French submarine to be completed between 1919 and 1944.

Construction and specifications

''O'Byrne'' and her two

sister ship A sister ship is a ship of the same Ship class, 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 o ...

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

Gironde Gironde ( , US usually , ; , ) is the largest department in the southwestern French region of Nouvelle-Aquitaine. Named after the Gironde estuary, a major waterway, its prefecture is Bordeaux. In 2019, it had a population of 1,623,749.

, being laid down in April 1917. However, Romania was forced out of the war in December 1917, when the construction of the three warships was at an early stage. The three submarines were subsequently completed for the French Navy, with larger

bridges A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somet ...

and

conning tower A conning tower is a raised platform on a ship or submarine, often armoured, from which an officer in charge can conn (nautical), conn (conduct or control) the vessel, controlling movements of the ship by giving orders to those responsible for t ...

s. ''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 52.4 meters in length, with a beam of 4.7 meters and a draught of 2.7 meters. Power plant consisted of two Schneider diesel engines and two electric motors powering two shafts, resulting in a surfaced top speed of 14 knots. Each vessel had a range of 1,850 nautical miles at 10 knots and a crew of 25. Armament consisted of four 450 mm torpedo tubes 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 east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

after

, but their careers were uneventful, and they were taken out of service before the start of

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. ''Louis Dupetit-Thouars'' was stricken in November 1928 and her two sisters in August 1935. 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 '' Delfinul'' in 1936.

References

{{DEFAULTSORT:O'Byrne Submarines of the French Navy Ships built in France World War I submarines of France World War I naval ships of Romania 1919 ships O'Byrne-class submarines