French Narval-class submarine

For other ships of the same name, see Narval-class submarine.
Espadon in Saint-Nazaire
Class overview
Operators:  Marine Nationale
In service: 1958 - 1992
Completed: 6
Retired: 6
Preserved: 1
General characteristics
Displacement: 1635 tons surfaced, 1910 tons submerged
Length: 78.4 m
Beam: 7.8 m
Draft: 5.2 m
Propulsion: 2 shafts, 2 × 7 cylinder diesel engines (4400 hp), 2 electric motors (5000 hp), re engined with new diesels in 1965-68
Speed:
  • 16 knots (30 km/h) surfaced
  • 18 knots (33 km/h) submerged
Range: 15,000 nautical miles (28,000 km) at 8 knots (15 km/h)
Test depth: 400 metres
Complement: 63
Armament: 8 × 550 mm torpedo tubes - 6 bow& 2 stern, 14 torpedoes carried

The Narval class (sous-marins d'escadre, "fleet submarines") were patrol submarines built for the French Navy in the 1950s.

Design

The Narval type was an offspring of the E-48 project, inspired by the German Type XXI U-boat of the Second World War, particularly the Roland Morillot brought into French service.

Compared to the Type XXI, the Narval introduced an entirely new schnorchel system and novel detection systems, gained 33% in operational range on electric power (400 nautical miles, compared to the 290 available to the type XXI), and doubled the test depth. The propellers were also particularly studied to minimise noise.

The hull of the Narvals was assembled from seven 10-metre sections wielded together.

The engine were 2-stroke diesels made by the French constructor Schneider, which proved unreliable and noisy to the point where the engine section became difficult to man at full power.

From 1966 to 1970, the Narval underwent extensive modernisation, where their engines were replaced by a diesel-electrical design based on the SEMT-Pielstick 12PA4-185. The 4 stern tubes were deleted, electronics were replaced, and the conning tower was replaced by a more modern sail plan from the Daphné class.

Careers

The Narval were used to explore limits of submarines performances in several ways.

In 1958, Dauphin and Requin broke the 30-day world record of the longest underwater cruise held by the nuclear USS Skate and Seawolf, with 32 and 42 days submerged respectively.

In 1964, Espadon and Marsouin sailed up to the 70th parallel north to prepare the first French attempts at navigation under sea ice. These tests were carried out the next year by Dauphin and Narval when they spent a week and a half in the 72nd parallel north.

During her last years, from 1980, Requin was fitted with the sonar system planned for the M4 refit of the SNLE. Similarly, Dauphin was extensively modified from 1986 to be used as a test bed for equipment and sensors to be installed on the Triomphant-class submarines, then under design. When finally decommissioned in 1992, she was the oldest submarine in service. She was later expended as a target ship off Toulon.

In 1985, Espadon became the first French submarine used as a museum ship.

Ships

Name Builder Completed Decommissioned
S631 Narval Arsenal de Cherbourg 1 December 1957 1986
S632 Marsouin Arsenal de Cherbourg 1 October 1957 1987
S633 Dauphin Arsenal de Cherbourg 1 August 1958 1992
S634 Requin Arsenal de Cherbourg 1 August 1958 1985
S637 Espadon AC Augustin Normand 2 April 1960 1985 - now a museum ship in Saint Nazaire
S638 Morse AC de la Seine Maritime 2 May 1960 1986

References

Wikimedia Commons has media related to Narval class submarine (1954).



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