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Weapons of Mass Destruction (WMD)


Pluton was a short range, road mobile, solid propellant, single warhead ballistic missile. Design of the Pluton started in the early 1960s, and the system entered service in 1974 with the French Army. Plans for a Super Pluton were dropped in 1983 in favour of a new missile programme, called Hades.

The Pluton missile was 7.64 m long and had a body diameter of 0.65 m. The missile had a launch weight of 2423 kg and the single stage solid propellant motor gave the missile a range of 120 km. Inertial guidance gave an estimated accuracy of 150 m CEP. The missile was believed to have conventional HE or nuclear warheads, with two nuclear warhead options at 15 or 25 kT depending upon the target. The missile was carried on a heavily modified AMX-30 tank chassis. Provision was made for real time targeting information to be passed to the Pluton command vehicle from a CT-20 drone. The Pluton system entered service in 1974, and it is believed that there were 30 launchers deployed with missiles, reloads and alternative warheads. The system was phased out of service in 1993.

Prime contractorAérospatiale, Space and Strategic Systems Division, Les Mureaux
Length 7.64 m
Body diameter 0.65 m
Launch weight 2423 kg
Payload Single warhead
Warhead HE or 15/25 kT nuclear
Guidance Inertial
Propulsion Single stage solid propellant
Range 120 km
Accuracy 150 m CEP

PRESTRATEGIC NUCLEAR MISSILE PROGRAMS Yves de ROUGEMONT 1 1. Introduction Before talking to you about the pre-strategic nuclear missile programs, I suggest, using a film of a few minutes, to remind you of the two systems currently in service, the Pluto in the Army, the ASMP in the 'Air Force. I will then try, after these images, which clearly illustrate the particularities of pre-strategic weapons, to give you a history of these systems. I will try to highlight what they have given us, not only as part of our deterrent force, but in their impact on our other programs. I will close by giving you an overview of the pre-strategic nuclear systems of the future. 2. Movie 3. The particularities of pre-strategic missiles As this film has shown you, what makes the difference between these pre-strategic missiles and the strategic ones that have been presented to you so far is of course their much smaller size and range, but it is also their conditions of use in more severe environments. Moreover, their former name of tactical nuclear missiles, which we rejected because it does not correspond to the policy of use of these weapons, on the other hand gave a little better account of theirmaterial conditions of use. The Pluto is carried by a chariot in all fields, through woods, for all time. The ASMP is mounted under the aircraft. They are no longer missiles that can be kept until they are fired in protected and air-conditioned enclosures. In this, they are directly related to our tactical missiles with conventional charge, and some of the techniques used are similar. 4. Pluto 4.1. Historical But let us return to history and to France's first steps in the field of pre-strategic nuclear missiles. The first studies of pre-strategic surface-to-surface missiles date from the beginning of the 1960s. The ranges envisaged were then modestly 30, then 40 km. Nord-Aviation and Sud-Aviation presented competing projects. The Vlan presented by Sud-Aviation was characterized by a ramp which was initially oriented according to firing corrections similar to those of a gun, in particular to reduce the effect of errors accumulated in the acceleration phase. The drag was then controlled to reduce errors in cruise. Nord-Aviation presented the SS-40 , with a simplified inertial guidance system that was derived from the work and experiments carried out between the end of the 1950s and the beginning of the 1960s for the AS-33 program . I remind you that the AS-33 missile was an Air-Sol 350 mm diameter with inertial guidance, the prototypes of which have been successfully tested. The inertial guidance, because of the small dimensions of the missile, was carried out by means of a vertical gyroscope directly carrying three accelerometers on its outer frame, an axial gyroscope, and a computer calculating the point, guiding and piloting the missile. The overall performance, lower than that of a complete inertia unit and its associated computer, was sufficient but above all much less bulky at the time and less expensive. The DMA (now the DGA) whose machinery department prefigured the future Machinery Department then asked, at the end of 1964, the two companies to propose a joint project. Nord and Sud-Aviation proposed the NS-10 project in February 1965. The requested range increased to 60 km, which definitively oriented the solution towards an inertial guidance system, the other version no longer allowing the required precision. It was not until 1967 that the military specification stabilized over a range exceeding 100 km. The NS-20 project was selected and development started. It was then that the program took its name. The Pluto was born. As part of the ongoing reorganizations of the aerospace industry at the time, Nord-Aviation was entrusted with the project management of the missile, Sud-Aviation keeping a significant part of the development (front point and telemetry - rear shell with the control surfaces). In 1970, when the two companies merged into Aerospace, the Tactical Engines Division of the new company, heir to Nord-Aviation, took over this responsibility. It was during this same year that the first guided shooting took place. Gradually, it was also entrusted with the equipment of the firing vehicle, then the overall project management of the missile and the firing vehicle, the CEA of course keeping the project management of the load, the SEFT that of the vehicle associated calculator. In May 1974, the first operational unit was formed, the 3rd RA of Mailly. Since then, five regiments have been operational in garrisons in eastern France and Champagne, the last since May 1978. 4.2. Brief description The system looks like you saw it in the movie. However, we can add some additional information on the course of the shooting. The equipment of the firing vehicle performs the following functions: - slaving of the support to the planned angle of site, - erection of the gyroscopes of the navigation center, - displays of the coordinates of the target and the explosion altitude of the load, - slaving of the support to the planned angle of site, - firing of the thruster. The following view represents one of the typical trajectories followed by the missile, throughout which it is piloted and guided towards its objective by aerodynamic control surfaces. A height detector triggers the explosion at the planned altitude. 4.3. Technical and technological contributions The Pluto program , because of the priorities assigned to it by the government, has prioritized the development of the necessary technologies. For the first time in France, a so - called cast-and-glue thruster was developed for a missile used in a tactical environment. This technique, already tested for the thrusters of the first strategic missiles, had to be adapted to withstand much more severe climatic and mechanical environments. For the first time, too, 180 hba roll-welded maraging propellant structures were produced. The thruster was developed by Aerospatiale with the support of SNPE and SEP. But it is in the field of guidance that a decisive impetus has been given. For the first time, a simplified inertial unit known as linked elements was used for an operational program. The conventional 3-axis stabilized power plant had to be avoided, judged to be too expensive for the required result. It is SFENA which has developed the necessary gyroscopes and accelerometers. The associated calculator, for its part, gave rise to long controversies as to the choice of principle. Analog or digital calculator? The technology of digital computers of the time did not make it possible to withstand the environmental and tactical conditions of use (for example: memories). It is Aerospatiale which has developed and produced the necessary high performance analog computer (precision of one thousandth). After nearly fifteen years of life, we still shoot Plutons with these calculators, which have also aged very well. The first beneficiary, after Pluto , of these developments was the Exocet . No need to remind you of the effectiveness of this world famous missile. The Exocet, therefore, benefited in its first versions, the MM-38 and AM-39, from the same inertial components and the same calculation techniques. It is good to note, as for the computer, that the entire missile largely met its storage reliability objectives. After 10 million hours of life and more than 4000 checks, it has reached an MTBF (mean time between failures) which is several times higher than the specified value. 4.4. Methodological contributions The Pluto was also an opportunity for our not only to face Division difficult technical problems, but also to tighten our working methods: - detailed technical clauses also serving as management tools, - qualification plans on the ground and in flight, - quality plan, - development plan, etc. These methodological tools were forged with the active support of the DGA's machinery department. They have also had a positive impact on conventional tactical missile programs, by streamlining the conduct of our programs. But we can also put to the credit of Pluto the generalization of hybrid simulations. These methods make it possible to represent in detail the operation of a whole complex guidance-piloting chain, including the real elements of a system. They guarantee before firing that the equipment fulfills its function correctly, and allow the same result to be achieved at a much lower cost. The ASMP , which I will now tell you about, fully exploited this methodology inaugurated with Pluto . 5. ASMP 5.1. Historical I will now tell you about the ASMP weapon system , the delivery of which to the Air Force, which began at the end of 1985, is actively continuing. From the start of the 1970s, reflections on the strategic airborne components ( Mirage IV equipped with the AN 22 bomb ) and pre-strategic ( Mirage III E then Jaguar and Super-Etendard equipped with the AN 52 bomb ) revealed the need to modernize this armament taking into account the progress of opposing ground-to-air defense systems. This is how the idea of ??replacing bombs with a missile capable of penetrating defenses and allowing the aircraft to remain at a safe distance quickly emerged. The first studies of such a missile date back to 1974 but they were put on hold with the abandonment of the program of the future combat aircraft ACF . In 1977, following a call for tenders launched by the Technical Department for Engines (DTEn) for the development of a medium-range missile intended to equip the Mirage 2000 , the Aerospatiale offered a new mode of propulsion: the ramjet with integrated accelerator whose principle was presented to you in the film. This proposal was the culmination of fundamental research work carried out by ONERA and Aerospatiale for several years. In 1978, the DEN chose Aerospatiale as prime contractor for the Medium Range Air-Ground Weapons System (ASMP) and notified it of its development. It was then a question of equipping the Mirage 2000 as part of a pre-strategic job. Of course, the CEA was the prime contractor for the nuclear load and AMD-BA for the adaptation of the aircraft. In 1979 the decision was taken to adapt the ASMP to the Mirage IV for strategic missions and this use became a priority. Meanwhile the plane was modernized to meet the needs of the mission, the Mirage IV P . In 1980, finally, it was decided to adapt the ASMP to the Super-Etendard for the needs of the French Navy in order to equip the aircraft carrier Foch . Despite the technical difficulties inherent in the new technologies used, series production of the missile was launched at the end of 1983 and the delivery deadlines set in 1978, 1979 and 1980 have been or will be respected, thus allowing the following operational steps: - entry into service of the 1st Mirage IV-ASMP squadron on May 1, 1986 for the benefit of the Strategic Air Forces (FAS), - entry into service of the 1st squadron M 2000 N - ASMP on July 1, 1988 for the benefit of the Tactical Air Forces (FATAC), - entry into service of the Super-Etendard-ASMP pair on the aircraft carrier Foch expected on June 1, 1989. 5.2. Brief description of the system He looks like you saw him in the movie. You can see from front to back: - the nuclear warhead (compared to Pluto : power 15 times greater for a mass 2 times less), - the guide block (compared to Pluto : about 4 times lighter), - the fuel tank, - the engine with its air inlets and its combustion chamber serving as an accelerator at the start of the flight. The nuclear warhead is assembled with the vector in a specialized workshop on an air base or aircraft carrier and the complete missile is then transported and hung under the aircraft either in the aircraft hangarette in the case of the Air Force, or on the bridge of flight in the case of the Navy. The attachment is done under the fuselage for the Mirage IV and the Mirage 2000 , under the wing for the Super-Etendard After a carry-in flight under the aircraft of a duration suited to the mission, possibly including a low-altitude penetration phase in ground following, the missile is ejected and moves at supersonic speed towards the goal in a fully autonomous manner, the data necessary for its navigation having been transmitted to it by the plane during the carriage. The high penetration capacity of the missile results from: - its speed more than bisonic, - its great maneuverability, - its discretion vis-à-vis radars, - its insensitivity to the effects induced by nuclear explosions, called hardening, - finally the variety of possible trajectories. When preparing for the mission, the user has the choice between: - a low-altitude trajectory at Mach 2, matching the topography as best as possible to avoid radars, whose range is lower but which is very penetrating, - a trajectory with cruising at high altitude and very high speed (Mach 3) with a dive on the steeply sloped objective which allows ranges of a few hundred kilometers, - finally a very low altitude trajectory adapted to marine objectives with permanent adjustment by the radio altimeter. The triggering of the load at the planned height is provided by the radio altimeter. The main Aerospatiale cooperators for equipment were: SAGEM for the inertia unit, ESD for the main computer, AIR EQUIPMENT for the rudder cylinders, ELECMA for the radio altimeter. 5.3 . Technological contributions At the time it was launched the program was extremely ambitious in terms of the performance required, given the knowledge of the time. It was therefore necessary to develop new technologies or significantly improve known ones. The main innovation was the development of a liquid fuel (kerosene) ramjet with integrated accelerator which made the propulsion system very compact. Compared to conventional powder propulsion, this engine formula allows significantly higher performance. (The specific impulse which is of the order of 200 to 250 s for the powder thrusters reaches 1300 s for the kerosene stato, because the missile does not have to carry with it the oxidizer, which is oxygen air). The development work was carried out in close collaboration with ONERA for the ramjet part and with SNPE for the integrated accelerator. This development required significant investments, in particular the construction of a test bench to operate the integrated accelerator, then the ramjet after the transition phase between the two speeds. This bench therefore comprises, associated with a powder rocket test bench, a supersonic wind tunnel capable of supplying the engine under all conditions of the missile's flight (pressure, speed and temperature at the engine inlet adjusted in real time and corresponding to the flight profile to be studied). This means installed in our Bourges-Subdray center gives us serious advantages for the development of new missiles subject to this formula. It seems interesting to underline that the remarkable performances of this type of engine are due to the association of the ramjet itself whose performances were already known for a long time (in France, with the Leduc planes, then missile CT-41 , Véga , SE-422, the Griffon ) and the electronic computer capable of controlling operating parameters extremely quickly and precisely. Given the very severe environmental conditions induced by the ramjet on the one hand (vibrations) and long-duration supersonic flight on the other hand (high skin temperature) we had to work very carefully on the design of the equipment to withstand this. new type of environment. We also had to develop high-speed piloting techniques in a vast altitude range (from 0 to 20,000 meters). This system has finally enabled us to develop techniques for hardening equipment and cabling to resist the effects induced by nuclear explosions. 5.4. Methodological contributions Under the impetus of the Directorate of Engines (DEN), the ASMP was also an opportunity for our Division to generalize and deepen the new methods explored with Pluto In particular, studies of the security of the system in peacetime linked to the nature of the load have been extremely thorough and result in the drafting of security reports submitted to the in-depth examination of committees specializing in this field, as practiced for nuclear charge or ballistic missiles (systematic study of feared events and the measures to be taken in consequence to avoid them: introduction of safety barriers on equipment, drafting of instructions for use, etc.). A great effort has also been made to control the quality of software through the creation of a software workshop working in close relation with that of the Division of Strategic and Space Systems of Aerospace and a methodology for writing and validation. We have also been able to develop, thanks to the power of the modern means of calculation at our disposal, mathematical models of the missile making it possible to predict very precisely on the ground the behavior of the missile in flight. These methods made it possible to limit the number of flight tests to the strict minimum with a maximum probability of success. They have a direct impact on new programs. 6. The pre-strategic systems of the future I have tried to describe to you the first steps of our industry in the field of pre-strategic nuclear missiles, with Pluto and ASMP . I must end with a glimpse of the future; I will tell you a word about Hades , for the near future, as well as the airborne ramjet sector, for the start of the next millennium. 6.1. Hades Intended to succeed Pluto , the Hades weapons system was the subject of a preliminary study phase of 5 years (1977-1982) before launching its development, entrusted today to the Strategic and Space Systems Division. of Aerospatiale. Its first flight test took place last November with full success and its entry into service is expected to begin at the end of 1992. The performance improvements specified over Pluto relate to: - the range, more than tripled, allowing both to shoot further and further; this last characteristic minimizes the need for all-terrain mobility and makes it possible to switch from a tracked carrier chassis to an unmarked all-road wheeled vehicle, whose road mobility is excellent, - precision, kept at maximum range despite the aforementioned increase in range, and achieved thanks to a strategic class inertial unit, - penetration, thanks to obtaining better stealth and better hardening of the vector and a very high maneuverability, - the implementation, clearly simplified thanks to the concept of full shot loaded on deposit on the launcher vehicle, as well as the self-alignment of the inertial unit of the missile which eliminates the need for the directing gyro-theodolith necessary for Pluto and , more generally, to the integration of all the functions necessary for firing in the launcher, which eliminates the need for additional vehicles such as the computer carrier or the Pluto power transmitter carrier . 6.2. The future The technological advance acquired with the ASMP makes it possible to envisage a new generation of firing airborne nuclear missiles with an even greater reach thanks to the in-depth exploitation of the advantages provided by the ramjet propulsion mode with integrated accelerator. These weapons would be characterized by considerably increased ranges, great precision, a great diversity of trajectories, a very low radar signature and therefore a very high penetration capacity. Preliminary technological studies are underway at Aerospatiale to demonstrate the feasibility of supersonic nuclear airborne missiles. It is mainly: - the readjustment of the navigation system during free flight of the missile, to guarantee accuracy, due to the increase in flight time which accompanies the increase in range; - long-lasting combustion chambers, with the development of various temperature resistance methods; - the development of materials resistant to kinetic heating in reduced masses and volumes due to high speeds and long durations; - modeling of shapes and the use of special materials to lower the radar equivalent surface. At the point where these studies stand, we can now say that the concept of such future missiles is validated. APPENDIX I Accompanying text for the movie Pluto The Pluto Weapons System , which today equips five of our Artillery regiments, is one of the important components of France's pre-strategic nuclear armament. The use of this weapon is political in nature. Therefore, the use of the Pluto system can only be decided by the Head of State. Only the maneuver of materials is organized and led by the regiment commander according to precise directives from the corps CP. The Pluto is a powder-powered supersonic missile. Its range can reach 120 km. The required precision and operational safety are ensured in flight by an on-board inertial system which guarantees autonomy and invulnerability to interference. The missile consists of two sets: the ammunition and the vector. Delivered separately in a container, they are assembled when loading onto the firing vehicle. The missile has a mass of about 2.5 tons, a length of 7.63 m and a diameter of 650 mm. The vector container serves as a launch pad. The vector comprises the thruster and the elements for piloting, guiding and triggering the warhead. The ammunition consists of a warhead comprising the nuclear charge. From the start of the pre-engagement phase, the vehicles making up the batteries return to their waiting position. The launcher vehicle is directly derived from the AMX-30 tank which also equips the Army * * A message arrives. Depending on the content of the message, the vehicles return to the position which has been designated to them. The firing section finds, at the fixed meeting point, the trucks which transported the loads constituting the missile. The vector container is undocked from the unloaded truck. It is removed by the crane, and placed on the site frame which thus serves as a support. It is then blocked by a quick locking system. The second burden, the ammunition, is then brought by his transport vehicle. Using the tank crane, the ammunition is extracted from its container; she still wears her protective shells. Its rear face is presented so as to engage the centering pins of the ammunition on the vector. The plugging in of the connectors is automatic, during the mechanical fixing of the head, carried out by 5 tie rods. The loaded vehicle may move to its firing position, or another standby position, if firing is not imminent. Not linked to road routes, the adaptation to the terrain of regimental equipment is sufficient to guard against an adverse nuclear strike. The tank is close to its firing position. The head protection shells can be removed in the standby position. The nuclear core loading operation then begins. The heart is brought in its transport and protection container. After extraction, it is introduced into the loading well. The firing order arrives at the command and liaison team. Immediately taken into account, it is transmitted in the form of a piece firing message. The launch vehicle returns to the position assigned to it beforehand, to fire at the scheduled time. The head of the piece turns the firing safety key, which, if the government authorization has arrived, initiates the final part of the sequence which includes, in particular, the raising of the site frame, the priming of the batteries, the unlocking of the missile on its ramp, the safety lift of the thruster, and the firing of the missile. The vehicle can immediately leave its position. The richness of its communication system, its mobility and its performance in terms of range and precision make Pluto a weapon which holds an eminent place in France's deterrent force. - - - APPENDIX II Accompanying text for the ASMP film To maintain the credibility of our nuclear deterrent, the government has decided to develop an Air-Sol missile fired from a backup, all-weather, fast, autonomous aircraft: this is the ASMP produced by Aerospatiale under the aegis of the Machinery Directorate. This missile can be fired from planes: - Mirage IV P , - Mirage 2000 N , - Super-Etendard . It measures 5.40 m, weighs 840 kg and has a caliber of 350 mm. It consists of two sets: - the nuclear warhead, - the vector, delivered separately in container. Its propulsion is provided by a kerosene ramjet comprising the accelerator powder block in its combustion chamber. This is the ramjet technique with integrated accelerator, the operation of which comprises the following phases: - firing of the powder block which allows the pressurization of the kerosene tank, - acceleration phase lasting 5 s which brings the missile to the flight conditions necessary for ignition of the ramjet, i.e. approximately M-2, - transition phase comprising in 1/10 of s: . ejection of the acceleration nozzle, . the opening of the air inlets, . the ejection of the shutters from the combustion chamber, . fuel injection and ramjet ignition, - finally, cruising phase with ramjet propulsion. Users have the choice between several types of trajectories: - low altitude trajectory, following the shapes of the relief, - high altitude trajectory, allowing a range of several hundred km, - marine trajectory at very low altitude. The preparation of a mission begins with the electrical control of the vector using an automatic test bench which checks its main functions. The nuclear warhead is then assembled with the container vector. Meanwhile, the missile launcher is brought under the plane. It is hoisted by means of standard winches, connected to the aircraft circuits and locked. The complete missile is then conveyed to the aircraft on a specific trailer designed to meet safety requirements during taxiing and handling. It is hoisted under the missile launcher and locked. Finally, the installation and connection of the pyrotechnic ejection cylinder is carried out. The Parameter Insertion Module (MIP) is used to introduce the missile flight program into the firing installation. Firing is preceded by an equipment heating phase and an inertial unit alignment phase. The firing sequence ends with the ejection of the missile. The accelerator powder block is ignited 1 second later, or approximately 10 m below the aircraft. The accelerator brings the missile to a Mach of the order of 2, necessary for the ignition of the ramjet. The autonomous guidance system controls the flight of the missile to the goal, which is achieved with great precision. With ASMP , air and naval air forces can conduct penetrating nuclear missions with increased reach without exposing themselves to the air defenses of their targets. Their dissuasive value is thus significantly improved.

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Page last modified: 10-12-2020 11:00:32 ZULU