@Picdelamirand-oil Know anything about the M51.3 upgrade?
The development of the M51.3, launched in 2014, is nearing completion and the challenge for the programme is the transition to the mass production of launchers. It should be understood that the 10th test firing of a Submarine Launched Ballistic Missile (SLBM) on 28 April 2021 from the DGA's Centre Essais de Lancement de Missiles (CELM) in Biscarrosse (Landes) was indeed a development firing of the M51.3. Once production was launched, the next step should be the constitution of a first batch and a synthesis firing that could be carried out at the beginning of the years 2023 to 2024 by Le Terrible, which was then leaving the IPER (2021 - 2023).
It was decided that the future vector of the oceanic component of the deterrent, in the perspective of the FMOD programme (Future Medium Oceanic Deterrent), which became a 3rd generation SSBN in 2013, would be an incremental evolution of the MSBS M51, instead of launching the "M6", as it was intended to be of much larger dimensions. This choice was justified by the interest of smoothing the budgetary flows and allowing a good conservation of industrial skills thanks to an incremental approach aiming at the replacement of a stage every 8 to 12 years (Laurent Collet-Billon, Délégué Général à l'Armement (28 July 2008 - 1 July 2017), hearing before the Defence and Armed Forces Commission, National Assembly, 30 April 2014).
The President of the Republic, Mr François Hollande, proclaimed his decision, on the occasion of his speech on deterrence, where he stated: "I have therefore also ensured, with regard to the oceanic component, to launch future adaptations of the M51 missile, to allow the tonnage of future submarines to remain very close to that of our Triumphant." (François Hollande, President of the Republic, Speech on nuclear deterrence - Visit to the strategic air forces. Istres, 19 February 2015).
At the strategic level, General Pierre de Villiers, Chief of Staff of the Armed Forces (15 February 2014 - 19 July 2017) defined the operational objectives of the M51.3 before the National Assembly, stating that it should "maintain the capabilities of our oceanic component in the face of the most severe missile defences, and which will have to enter into service in the middle of the next decade when the M51.1 comes to the end of its life" (Hearing before the Committee on Defence and the Armed Forces, National Assembly, 6 May 2014).
On the industrial level, the DGA awarded the contract for the development and production of the M51.3 to ArianeGroup, which is the prime contractor for the M51 programme, in July 2014. Development work on this new version began in August 2014 and is scheduled to last 10 years, with a gradual increase in the volume of work related to its development. And this programme is closely linked, in terms of skills and therefore technological building blocks, to the Ariane VI programme.
The initial design phase of the M51.3 is said to have taken place between August 2014 and 2016. The detailed design phase would have started in 2016 and is expected to be completed in 2024. The main commitments in 2020 cover further development and production work on the M51.3 version.
In terms of capability, the M51.3 will benefit from an evolution of its payloads. This means that the Oceanic Nuclear Warhead (ONW), which entered into service in 2016, should coexist with or be replaced by the ONW 2, starting in 2025. New developments are also expected for the penetration aids which are located on the upper part of the MSBS. The third stage of the M51 is also expected to be renovated during the development of its third version. Indeed, the propulsion of this stage and its equipment are largely derived from the M45.
These material evolutions will make it possible to support the evolution of operational needs in terms of precision, flexibility of use, range and thus penetration of adversary defences: the M51.3 should happily exceed 10,000 km of range.
Improvements in range and accuracy will largely depend on the development of new Reentry Vehicles (RVs), which could therefore fall under the MaRV umbrella. The English-language open literature understands - without ever citing a source - that the TN-75 and its re-entry body had a mass of 230 kg, of which 115 kg was the warhead. The M51.2 brought a new upper part, as the M51.1 had inherited the one from the M45. The TNO, according to the above-mentioned literature, would have a mass of 500 to 550 kg, taking into account the re-entry body. The power rating of the TNO is regularly presented as 100, 150 or 300 kT.
The evolution of France's nuclear doctrine revealed in President Jacques Chirac's so-called "Ile Longue" speech (19 January 2006). He said that the ultimate warning to the adversary could be aimed at the "centres of power, at its capacity to act" and that in this perspective "all our nuclear forces have been configured in this spirit. It was with this in mind, for example, that the number of nuclear warheads was reduced on some of the missiles in our submarines.
Will the evolution of the "flexibility of use" contained in the M51.3 affect not the number of payloads, and thus the number of warheads, integrated into the third stage, but the nominal power of the TNO 2? Adapting the number of warheads is a first modulation of the delivered power and thus of the possibilities to deliver, for example, a "final warning". There would be two main ways to offer new flexibility in the proposal of options to restore deterrence: a frankly reduced power on some TNO 2s, constituting a sub-version; an adjustable power in the manner of the ASMP-A/ASMP-A RMV TNA (Airborne Nuclear Warheads).
It is therefore also expected to improve the penetration of adversary defences by carrying out work on other payloads: the Aides à LA Pénétration (ALAP). Their origins go back to the S3D and the M4. The TN-70 was not stealthy. Faced with the improvement of adversary defences, in particular in terms of radar coverage, the M4 71 was quickly put under study. The development of a jamming system was also envisaged for this one. A TN-75 with the advantages of stealth thanks to a very small Radar Equivalent Surface (RES) was developed. The Minister of Defence, André Giraud (20 March 1986 - 10 May 1988), suspended the work for several months. He was given proof that the three Soviet radar layers could identify and track the TN-75, despite its reduced SER: with the risk that ballistic missile defences could, in the long term, discriminate between them in order to intercept them. He decided to launch an upstream study programme in 1986: EBAP (Basic Studies of Penetration Aids), which followed on from EXHANP (High Altitude Expansion of a Chaff Cloud). Its results were integrated into the M45, whose entry into the realisation phase was decided at a Military Nuclear Committee, chaired by the new Minister of Defence, Mr Jean-Pierre Chevènement (12 May 1988 - 29 January 1991) in 1988. The successors to the ALAPs of the EBAP programme are not well detailed in the literature.
It is in this perspective that the 10th test firing of an M51 Submarine Launched Ballistic Missile (SLBM) should be assessed. Mrs Florence Parly, Minister of the Armed Forces, expressed her great satisfaction after the success, on 28 April 2021, of what was also the 5th test firing from DGA Essais de Missiles in Biscarrosse (Landes), which appears to be destined to serve the development of the M51.3, which is expected to enter service by 2025.
This firing differs from the previous ones because it was not a qualification or validation firing for its implementation by a Le Triomphant-class SNLE-NG/SN2G (4). However, its trajectory presented in HYDROLANT 1140/21(GEN) showed some similarities, notably the fallout zones of the three stages of the missile, with the 9th firing of 12 June 2020, carried out as a validation firing of the IAM51 of the SNLE-NG/SN2G Le Téméraire (1999) launching from Audierne Bay. This 9th shot, here of an M51.2, had then travelled 6,000 km and reached a peak of 1,200 km against, and around, 5,500 km for the 10th shot.
Moreover, this invites us to reconsider the 9th firing because it took place nearly a year after the return to the operational cycle of the SNLE-NG Le Téméraire (1999), at the end of its IAM51. The SNLE could only be considered as operational, otherwise the patrols conducted would be null and void. Does this mean that this validation firing could also have been used to develop the M51.3?
But the 28 April 2021 firing also presented some intriguing facts, such as the fact that the trajectory of the three phases of flight (propulsion, ballistic and atmospheric re-entry) were not aligned with the target zone: so that the final phase of the flight until it reached the target zone appeared to be non-ballistic. This raises the question, in addition to the existence of manoeuvres, of their place of occurrence: from the end of the propulsion phase? During the outer space phase?
The trajectory of the 10th shot could have been the occasion for some work relating, for example, to 'lateral offset': this is the distance between the actual point of arrival on the ground of a spacecraft or payload that has had a phase of outer space flight and the vertical projection on the ground of the trajectory it would have followed in the absence of transverse aerodynamic effects. A Maneuverable Reentry Vehicle (MaRV) payload could have been used for this purpose.
The earlier the warheads are released, the more the adversary defences have to deal not with a high end but with multiple payloads, between the warheads and the penetration aids. This implied a capability for lateral offset of the upper part (Post-Boost Vehicle (PBV), according to the SALT II treaty term, or Payload Bus) or of one of its payloads.
Several hypotheses can therefore be combined:
The fact that the upper part could manoeuvre so that its payloads of the MIRV (Multiple Independently Targeted Reentry Vehicle) type, including the military payloads - Oceanic Nuclear Warheads (ONW) - could be placed on new independent trajectories, and off the launch axis, in order to reach the target zone.
Another hypothesis is that one of the payloads has intrinsic manoeuvrability, served by its own navigation system, and can therefore be described as a Maneuverable Reentry Vehicle (MaRV).
The detailed design phase is expected to be completed by August 2024, with a hypothetical slippage of the schedule from several weeks to several months depending on the possible consequences of the health crisis; difficulties arising during the design and development phases may also occur.
The publication of the above-mentioned job offer would mean, at the very least, that actions to improve production processes will be implemented. The second quarter or even the second half of 2022 would initiate the transition to serial production of the M51.3 MSBS. This would follow or precede the first "tests" at the various sites concerned.
As mentioned above (cf. remarks by Mr Laurent Collet-Billon, former Délégué Général à l'Armement (28 July 2008 - 1 July 2017), the transition from the M51.2 to the M51.3 does not consist of the production of a new batch of M51 MSBSs but of the replacement of one of the missile's elements by one or more new ones. In this context, it would be understood that new third stages will be machined, or even new payloads will be installed on the new upper part of the M51.2. The first batch of M51.3s would proceed from the assembly of these new elements on the occasion of the IPER exit (2021 - 2023) of the SN2G Le Terrible, which would then be in the power-up phase in order to return to the operational cycle. One of the three batches of M51 MSBS would then be made available thanks to the preparation for the entry into IPER of the SN2G Le Triomphant (2025?).
One of the major objectives - in addition to possible acceptance firings that could be carried out by the DGA's Centre Essais de Lancement de Missiles (CELM) at Biscarrosse (Landes) - will be the constitution of a complete batch of this new version and a synthesis or validation firing that could be carried out at the beginning of the years 2024 to 2025 by a SNLE. The fact that Le Terrible will then be out of IPER (2021-2023) seems to indicate that it is the ideal candidate for this firing: was it not the first SNLE-NG to fire the M51.1, on 27 January and 10 July 2010, as a prelude to its admission to active service?