Le Redoutable and L'Inflexible Class


Nationality: France

France decided that to maintain any semblance of independence in its nuclear deterrent it must develop its own submarine designs and the missiles to be carried. It therefore rejected the American offer of Polaris.

The Le Redoubtable was laid down in 1964 and put to sea in the late 1960s. It then spent more than two and a half years acting as a development vessel, undertaking trials. It was not until 1971 that it was commissioned.

It is always difficult to discuss the French SSBNs with a single equipment fit as they were constantly undergoing upgrades. Le Redoutable and her sister Le Terrible were initially fitted with the 2400km M1 SLBM with a single warhead. But by 1974 the third vessel, Le Foudryant went into service with the longer range 3100km M2 SLBM. The two earlier boats then underwent overhauls and were retrofitted with the M2 SLBM.

L’Indomptable was the fourth submarine to go into service in 1977. She had the vastly improved M20 missile. This missile had the same range and accuracy of the earlier M2 but had a number of chaff-dispersing penetration aids. The final vessel, Le Tonnant went into service in April 1980. It was also equipped with the M20 missile system. The first three units were retrofitted with the M20 system as they underwent overhauls.

From 1985 onwards the last four vessels in this group were modified to carry the M4 SLBM. At about the same time all five were converted to carry the SM39 Exocet anti-ship missile and their sonar was upgraded to the L’Infexible standard. The French Navy began to retire the class at the end of 1991 when they paid off Le Redoutable.

The single example of the L’Inflexible class was laid down in 1980 and came into operational service in 1985. This vessel could best be described as an intermediate design between the first and latest generation of French SSBNs This submarine looks very like the other Le Redoutable class vessels but has a much more advanced internal fit in propulsion, weapons, electronics and sensors.

This sixth boat had a great deal to do with the French belief that they needed three SSBNs to be constantly available and two of these must be at sea. With only five boats in Le Redoutable class, the L’Inflexible made up the numbers.

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