The M51 is scheduled to replace the M45 missile in 2010. The first development work on the M45 dates back to 1973, followed by its first operational firing in 1985. Compared to the M45, the new generation of M51 missiles will offer a significant increase in range. 

The 56 metric tons of the M51 will be steered by an inertial guidance system and powered by solid propellant.

It can deliver its payload of several nuclear warheads to targets up to 6,000 km away. It has three propulsion stages, the third of which is integrated into the equipment bay. The first stage of the M51 operates at a pressure of approximately 100 bar and produces about 180 metric tons of thrust. The upper part has an equipment bay, and a system for releasing the warheads independently.

 

The main operational objectives for the M51 program, developed in respect of France’s “no first strike” policy, are the same as those for the M45 program, i.e.:

· ensuring the nuclear safety and security of the weapon system through the use of appropriate technologies

· enhancing the invulnerability of the next generation of missile-launching nuclear submarines, notably through increasing the patrol zones

· maintaining strike capability to keep ahead of the improvements in ballistic anti-missile defense systems up until 2030

· providing the capacity to adapt to new threats and missions.

 

The M51 program is one aspect of the Cœlacanthe project set up by the French defense procurement agency, the Délégation Générale pour l’Armement (DGA) which has been tasked with putting in place the oceanic strategic defense system. The prime contractor for the missile is Astrium with G2P (an economic interest grouping of Snecma Propulsion Solide with SNPE Matériaux Energétiques) the prime contractor for the propulsion component. 

Since 2004 the M51 program has been in the production phase. A M51.2 version will be brought into service at a later date to accommodate the oceanic nuclear warhead (TNO) developed by the French Atomic Energy Commission (CEA).