The M20 was a French submarine-launched ballistic missile (SLBM) deployed on the nuclear s from 1977. It was withdrawn from service by 1991.

History

The M20 was the third member of the MSBS (''Mer-Sol-Balistique-Stratégique'', "sea-ground ballistic strategic") family which comprised a number of submarine-launched, intermediate range missiles. The force constitutes the second leg of the French nuclear deterrent force. The M1 version went into service in 1971 and was phased out in favour of the M2 in 1974, itself replaced by the M20 in 1977. The new M4 missile entered service in 1985 and has replaced the M-20. French nuclear-powered submarines ( SNLE: ''Sous-marin Nucléaire Lanceur d'Engins'', "Nuclear Device-Launching Submarine"), are able to carry 16 missiles each. The oldest ship, ''Redoutable'', was not converted to carry the M-4 and was withdrawn from service in 1991. Logistical support for the MSBS fleet is provided by the

Île Longue Île Longue ( French for "Long Island") is a peninsula of the roadstead of Brest in the department of Finistère in the Brittany region. It is the base of the SNLE, the French ballistic missile submarines, and as such one of the most secretive ...

Naval Base in Brest Bay, where the assembly and storage facilities for maintenance of readiness are located. Three SSBNs are intended to be operational at any one time. The M20 system entered service in 1977. There were 100 missiles produced, and the M20 ceased operational deployment in 1991.

Technical

The M-20 was a two-stage,

solid propellant A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...

, intermediate-range ballistic missile, 10.4 m in length and 1.5 m in diameter. Launch weight was 20,000 kg and the missile had a range of 3,000 km. Control of the first stage was by four

gimbal A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of ...

led nozzles; the second stage by

thrust vector control Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the ve ...

through a single fixed nozzle. The first stage propellant weighed 10,000 kg and burned for 55 seconds, the second stage propellant weighed 6,015 kg and burned for 58 seconds. Guidance was

inertial In classical physics and special relativity, an inertial frame of reference (also called inertial reference frame, inertial frame, inertial space, or Galilean reference frame) is a frame of reference that is not undergoing any acceleration. ...

. The payload was believed to include some penetration aids and the single re-entry vehicle had some hardening against nuclear effects. The TN-60 warhead was reported to yield 1.2 Mt.

Operators

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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 ...

References

External links

George C. Marshall George Catlett Marshall Jr. (December 31, 1880 – October 16, 1959) was an American army officer and statesman. He rose through the United States Army to become Chief of Staff of the US Army under Presidents Franklin D. Roosevelt and Harry ...

and

Claremont Institute The Claremont Institute is a conservative think tank based in Upland, California. The institute was founded in 1979 by four students of Harry V. Jaffa. It produces the ''Claremont Review of Books,'' ''The American Mind'', and other publications. ...

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French SLBM
Submarine-launched ballistic missiles of France Nuclear weapons of France Projects established in 1977 1977 in military history 1970s in France 1970 establishments in France 1991 disestablishments in France Military equipment introduced in the 1970s {{Missile-stub