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13,000 km Ballistic Missile: A Step Toward Iran’s Intercontinental Nuclear Missile
To the lofty spirit of the martyred Leader, who, with insight and steadfastness against corrupt and dependent domestic currents, prevented the national disarmament and ensured the continuation of Iran’s defensive independence.
The combined propulsion system includes 4 main engines from the Simorgh satellite launcher and 4 auxiliary boosters (each with 4 engines similar to the main engine) designed to increase the ballistic missile’s range to 13,000 km. The generated thrust is sufficient to launch the Soviet atomic missile (R-7 Semyorka). Guidance is provided by an independent INS with an error of 5 to 10 km, which is sufficient and acceptable for nuclear deterrence and the threat of destroying an American city. The non-maneuvering nuclear warhead, utilizing hypersonic materials and an ablative heat shield similar to the Hwasong-17 structure, is designed to withstand the severe heating of re-entry.
Thermal Protection of the Nuclear Warhead on a 13,000 km Trajectory
When an intercontinental warhead returns toward its target after traveling thousands of kilometers, it faces one of the most extreme thermal environments imaginable in aerospace engineering. During the re-entry phase, the warhead reaches speeds of several times the speed of sound, and the air in front of it is intensely compressed and heated. As a result, temperatures at the front of the warhead reach several thousand degrees Celsius, creating conditions where, without thermal protection systems, structural destruction is inevitable.
To better understand this, consider the trajectory of an intercontinental warhead such as that of the Hwasong-17 missile. After the rocket motors finish their work, the warhead continues its path outside the atmosphere. Then, in the final phase of the mission, it enters the dense layers of Earth’s atmosphere at extremely high speed. At this moment, the most intense thermal and aerodynamic loads are applied to the warhead, and its survival until reaching the target depends entirely on the performance of the thermal protection system.
The classic and proven solution for passing through this harsh environment is the use of ablative heat shields. Contrary to popular belief, these shields do not deflect heat; instead, they absorb thermal energy by gradually consuming themselves. The outer layers of the shield decompose, melt, or vaporize due to heat, carrying away a large portion of the thermal energy in the process. As a result, the temperature of the inner layers and the main payload remains within a tolerable range.
This technology is based on the laws of thermodynamics and heat transfer. Materials such as phenolic resins, carbon-phenolic composites, and other ablative materials undergo controlled decomposition when exposed to intense heat flux. This endothermic process reduces heat transfer to the main structure. For this reason, ablative shields have been used for decades in spacecraft capsules, re-entry vehicles, and ballistic warheads.
In advanced systems, the ablative shield is not the only part of the thermal protection. In sensitive areas such as the nose and aerodynamic edges, Ultra High Temperature Ceramics (UHTC) and carbon composites are used. These materials have a different role: instead of being consumed, they preserve the aerodynamic shape and structural strength at very high temperatures. Therefore, in many designs, ablative shields and ultra-high-temperature materials complement each other rather than replace one another.
In recent years, Hypersonic Glide Vehicles (HGV) have also attracted significant attention. These systems, unlike conventional ballistic warheads, are capable of gliding and maneuvering after entering the atmosphere. This feature causes them to spend more time in the hot atmospheric environment, making their thermal challenges more complex than those of classical ballistic warheads. Therefore, thermal protection design for HGVs typically requires a combination of ablative shields, ultra-high-temperature materials, and advanced aerodynamic solutions.
The Fattah-2 missile is equipped with a gliding warhead (HGV). Official domestic sources have also spoken of its gliding capability, maneuverability, and trajectory-changing ability. Therefore, it can be said that, according to the officially published description, the announced mechanism for Fattah-2 is consistent with the HGV concept.
Another important topic is the connection between space technology and re-entry technology. Returning a spacecraft capsule safely from Earth’s atmosphere without using thermal protection systems is impossible. Therefore, success in recovering payloads or capsules demonstrates the acquisition of part of the knowledge of re-entry, aerodynamic heating analysis, and heat shield design.
Ultimately, if a country has achieved ablative shield technology, high-temperature resistant materials, and re-entry vehicle design, it has solved a significant part of the problem of warhead survival during atmospheric re-entry. For this reason, ablative shields remain one of the most important aerospace technologies — a technology that plays a vital role, from spacecraft capsules to long-range warheads, in surviving the thermal hell of atmospheric re-entry.
The key point is that in a non-maneuvering ballistic warhead, similar to what is considered for intercontinental warheads, the combination of an ablative heat shield and high-temperature resistant materials can be the main factor in the warhead’s survival during re-entry. The ablative shield reduces the thermal load on the structure by absorbing and dissipating most of the thermal energy through controlled ablation and decomposition, while ultra-high-temperature materials and advanced composites used in hypersonic vehicles preserve the aerodynamic shape and strength of sensitive points.
This combination allows the warhead to withstand severe re-entry heating and continue to the target without melting or disintegrating due to heat. Therefore, the simultaneous use of ablative shields and high-temperature resistant materials is one of the fundamental principles in the design of re-entry vehicles and long-range warheads.
The combination of ablative shields and high-temperature resistant materials of the type used in hypersonic systems is a proven solution for protecting the warhead during atmospheric re-entry. Given Iran’s achievements in the field of thermal protection, re-entry vehicles in space activities, and hypersonic warheads, it can be said that a significant part of the thermal challenge of such a mission is manageable.
This is not merely theoretical; it has been practically proven through the successful recovery of Iran’s 500 kg biological capsule in Azar 1402 (November/December 2023), which was equipped with a “thermal shield system and ablative system,” the successful launch and return of previous biological capsules such as the “space monkey” in 1392 (2013), and the design of new generations of recoverable capsules for orbital biological experiments and the Pishgam explorer.
Therefore, from the perspective of solving the extreme heat problem, existing technologies can prevent a non-maneuvering ballistic warhead from melting or disintegrating under conditions similar to intercontinental warheads like the Hwasong-17 — using an ablative shield and hypersonic warhead materials.
Of course, from a scientific standpoint, it should be noted that there is a significant difference between the return of a suborbital spacecraft capsule and the re-entry of an intercontinental warhead. Intercontinental warheads enter the atmosphere at much higher speeds and therefore face much more severe thermal and aerodynamic loads. Thus, success in recovering spacecraft capsules alone does not mean complete proof of performance under intercontinental warhead conditions.
Nevertheless, these achievements demonstrate the acquisition of a significant portion of the knowledge in designing ablative shields, re-entry heating analysis, high-temperature resistant materials, and recoverable vehicle technology. Therefore, with proper design and necessary testing, a significant part of the thermal challenge related to the survival of a non-maneuvering ballistic warhead during atmospheric re-entry is manageable. Given Iran’s announced record and achievements in re-entry technologies, thermal protection, and hypersonic systems, it can be assessed that the necessary scientific and technical infrastructure for developing ablative shields suitable for advanced missions like the Hwasong-17 has been provided to a considerable extent.
Propulsion Power Equivalent to the Soviet Atomic Missile Using Indigenous Technology
In analyzing rocket motor thrust, a distinction must be made between stage type, fuel type, booster configuration, and the motor’s operating environment. Mounting a motor on a booster does not by itself reduce thrust; the main factors affecting thrust are ambient pressure and nozzle design.
The first stage of a rocket operates in dense atmosphere and its nozzle is optimized for sea-level conditions, while upper stages operate in rarefied atmosphere or vacuum and usually use nozzles with larger expansion ratios for higher efficiency. Therefore, a motor generally produces more thrust in vacuum than at sea level.
This principle applies to both solid-fuel and liquid-fuel motors. As ambient pressure decreases, nozzle performance improves in both types. However, liquid motors, due to more advanced design possibilities, thrust control, and sometimes adjustable nozzles, usually achieve higher efficiency in upper stages and vacuum conditions. In contrast, the main advantages of solid motors are simplicity, rapid readiness, and long-term storability.
For example, if the first stage has 1,100 kN of thrust and four auxiliary boosters each produce 1,100 kN, the total system thrust reaches approximately 5,500 kN. This shows that boosters are used to increase total thrust, and simply mounting motors on boosters does not cause a drop in thrust.
An example of this approach can be seen in the R-7 Semyorka, which used a central core and four side boosters. This design shows that motor performance depends more than anything on matching the nozzle to the operating environment, not on its mounting location.
Consequently, if a sea-level-designed motor with 1,100 kN thrust is mounted on a booster operating in the same atmospheric conditions, its thrust will remain approximately the same. Thrust reduction occurs when the nozzle design is not compatible with the motor’s environmental conditions, not merely because it is a booster motor.
Technical estimates indicate that the thrust of the Simorgh satellite launcher’s first stage is about 1,393 kN; however, for a conservative approach in analyses, we use 1,100 kN. On the other hand, assuming Iran has not yet achieved nuclear warhead miniaturization, the weight of the warhead for a potential intercontinental ballistic missile, similar to first-generation Soviet warheads (R-7 Semyorka), is considered to be about 5 tons.
If we equip the missile with four side boosters (each producing 1,100 kN of thrust), the total thrust at liftoff (including the central stage thrust plus 4 boosters) will reach 5,500 kN. According to aerospace engineering principles, this amount of thrust is entirely sufficient to launch a heavy ballistic missile with a “gross liftoff weight” of approximately 285 tons and can successfully carry a payload including the same 5-ton warhead.
From a scientific perspective, any country that builds a two- or three-stage satellite launcher possesses all the basic technologies for an intercontinental ballistic missile (ICBM), because both share the same principles of propulsion, stage separation, inertial guidance, and aerodynamics.
Iran has demonstrated this capability with launchers such as Qased, Qaem-100, Zuljanah, Simorgh, and Safir. The difference between a satellite launcher and an ICBM lies in the payload (orbital vs. warhead), accuracy (several kilometers vs. hundreds of meters), and operational readiness — all of which are engineering challenges, not scientific barriers. Therefore, converting a satellite launcher into an ICBM is a strategic decision, not a new technological leap.
Inertial Navigation (INS): Accuracy Sufficient for Deterrence
The guidance structure of long-range ballistic missiles consists of three main layers:
Mid-course phase with an Inertial Navigation System (INS) that covers more than 90% of the path. This system is completely independent but has an error of 5 to 10 km over 13,000 km range, which is acceptable for urban targets.
Mid-course correction using astronomical navigation (accuracy 100–300 meters, independent and jam-resistant) or satellite navigation (China’s BeiDou system with several-meter accuracy, but dependent on China).
Terminal phase radar/imaging seeker (50–100 km from target) that achieves accuracy below 10 meters using 3D imaging.
For nuclear deterrence (such as the threat of destroying Washington), the first layer alone with an accuracy of about 2.5 km (CEP) is sufficient — there is no need for pinpoint accuracy.
farsnews.ir
To the lofty spirit of the martyred Leader, who, with insight and steadfastness against corrupt and dependent domestic currents, prevented the national disarmament and ensured the continuation of Iran’s defensive independence.
The combined propulsion system includes 4 main engines from the Simorgh satellite launcher and 4 auxiliary boosters (each with 4 engines similar to the main engine) designed to increase the ballistic missile’s range to 13,000 km. The generated thrust is sufficient to launch the Soviet atomic missile (R-7 Semyorka). Guidance is provided by an independent INS with an error of 5 to 10 km, which is sufficient and acceptable for nuclear deterrence and the threat of destroying an American city. The non-maneuvering nuclear warhead, utilizing hypersonic materials and an ablative heat shield similar to the Hwasong-17 structure, is designed to withstand the severe heating of re-entry.
Thermal Protection of the Nuclear Warhead on a 13,000 km Trajectory
When an intercontinental warhead returns toward its target after traveling thousands of kilometers, it faces one of the most extreme thermal environments imaginable in aerospace engineering. During the re-entry phase, the warhead reaches speeds of several times the speed of sound, and the air in front of it is intensely compressed and heated. As a result, temperatures at the front of the warhead reach several thousand degrees Celsius, creating conditions where, without thermal protection systems, structural destruction is inevitable.
To better understand this, consider the trajectory of an intercontinental warhead such as that of the Hwasong-17 missile. After the rocket motors finish their work, the warhead continues its path outside the atmosphere. Then, in the final phase of the mission, it enters the dense layers of Earth’s atmosphere at extremely high speed. At this moment, the most intense thermal and aerodynamic loads are applied to the warhead, and its survival until reaching the target depends entirely on the performance of the thermal protection system.
The classic and proven solution for passing through this harsh environment is the use of ablative heat shields. Contrary to popular belief, these shields do not deflect heat; instead, they absorb thermal energy by gradually consuming themselves. The outer layers of the shield decompose, melt, or vaporize due to heat, carrying away a large portion of the thermal energy in the process. As a result, the temperature of the inner layers and the main payload remains within a tolerable range.
This technology is based on the laws of thermodynamics and heat transfer. Materials such as phenolic resins, carbon-phenolic composites, and other ablative materials undergo controlled decomposition when exposed to intense heat flux. This endothermic process reduces heat transfer to the main structure. For this reason, ablative shields have been used for decades in spacecraft capsules, re-entry vehicles, and ballistic warheads.
In advanced systems, the ablative shield is not the only part of the thermal protection. In sensitive areas such as the nose and aerodynamic edges, Ultra High Temperature Ceramics (UHTC) and carbon composites are used. These materials have a different role: instead of being consumed, they preserve the aerodynamic shape and structural strength at very high temperatures. Therefore, in many designs, ablative shields and ultra-high-temperature materials complement each other rather than replace one another.
In recent years, Hypersonic Glide Vehicles (HGV) have also attracted significant attention. These systems, unlike conventional ballistic warheads, are capable of gliding and maneuvering after entering the atmosphere. This feature causes them to spend more time in the hot atmospheric environment, making their thermal challenges more complex than those of classical ballistic warheads. Therefore, thermal protection design for HGVs typically requires a combination of ablative shields, ultra-high-temperature materials, and advanced aerodynamic solutions.
The Fattah-2 missile is equipped with a gliding warhead (HGV). Official domestic sources have also spoken of its gliding capability, maneuverability, and trajectory-changing ability. Therefore, it can be said that, according to the officially published description, the announced mechanism for Fattah-2 is consistent with the HGV concept.
Another important topic is the connection between space technology and re-entry technology. Returning a spacecraft capsule safely from Earth’s atmosphere without using thermal protection systems is impossible. Therefore, success in recovering payloads or capsules demonstrates the acquisition of part of the knowledge of re-entry, aerodynamic heating analysis, and heat shield design.
Ultimately, if a country has achieved ablative shield technology, high-temperature resistant materials, and re-entry vehicle design, it has solved a significant part of the problem of warhead survival during atmospheric re-entry. For this reason, ablative shields remain one of the most important aerospace technologies — a technology that plays a vital role, from spacecraft capsules to long-range warheads, in surviving the thermal hell of atmospheric re-entry.
The key point is that in a non-maneuvering ballistic warhead, similar to what is considered for intercontinental warheads, the combination of an ablative heat shield and high-temperature resistant materials can be the main factor in the warhead’s survival during re-entry. The ablative shield reduces the thermal load on the structure by absorbing and dissipating most of the thermal energy through controlled ablation and decomposition, while ultra-high-temperature materials and advanced composites used in hypersonic vehicles preserve the aerodynamic shape and strength of sensitive points.
This combination allows the warhead to withstand severe re-entry heating and continue to the target without melting or disintegrating due to heat. Therefore, the simultaneous use of ablative shields and high-temperature resistant materials is one of the fundamental principles in the design of re-entry vehicles and long-range warheads.
The combination of ablative shields and high-temperature resistant materials of the type used in hypersonic systems is a proven solution for protecting the warhead during atmospheric re-entry. Given Iran’s achievements in the field of thermal protection, re-entry vehicles in space activities, and hypersonic warheads, it can be said that a significant part of the thermal challenge of such a mission is manageable.
This is not merely theoretical; it has been practically proven through the successful recovery of Iran’s 500 kg biological capsule in Azar 1402 (November/December 2023), which was equipped with a “thermal shield system and ablative system,” the successful launch and return of previous biological capsules such as the “space monkey” in 1392 (2013), and the design of new generations of recoverable capsules for orbital biological experiments and the Pishgam explorer.
Therefore, from the perspective of solving the extreme heat problem, existing technologies can prevent a non-maneuvering ballistic warhead from melting or disintegrating under conditions similar to intercontinental warheads like the Hwasong-17 — using an ablative shield and hypersonic warhead materials.
Of course, from a scientific standpoint, it should be noted that there is a significant difference between the return of a suborbital spacecraft capsule and the re-entry of an intercontinental warhead. Intercontinental warheads enter the atmosphere at much higher speeds and therefore face much more severe thermal and aerodynamic loads. Thus, success in recovering spacecraft capsules alone does not mean complete proof of performance under intercontinental warhead conditions.
Nevertheless, these achievements demonstrate the acquisition of a significant portion of the knowledge in designing ablative shields, re-entry heating analysis, high-temperature resistant materials, and recoverable vehicle technology. Therefore, with proper design and necessary testing, a significant part of the thermal challenge related to the survival of a non-maneuvering ballistic warhead during atmospheric re-entry is manageable. Given Iran’s announced record and achievements in re-entry technologies, thermal protection, and hypersonic systems, it can be assessed that the necessary scientific and technical infrastructure for developing ablative shields suitable for advanced missions like the Hwasong-17 has been provided to a considerable extent.
Propulsion Power Equivalent to the Soviet Atomic Missile Using Indigenous Technology
In analyzing rocket motor thrust, a distinction must be made between stage type, fuel type, booster configuration, and the motor’s operating environment. Mounting a motor on a booster does not by itself reduce thrust; the main factors affecting thrust are ambient pressure and nozzle design.
The first stage of a rocket operates in dense atmosphere and its nozzle is optimized for sea-level conditions, while upper stages operate in rarefied atmosphere or vacuum and usually use nozzles with larger expansion ratios for higher efficiency. Therefore, a motor generally produces more thrust in vacuum than at sea level.
This principle applies to both solid-fuel and liquid-fuel motors. As ambient pressure decreases, nozzle performance improves in both types. However, liquid motors, due to more advanced design possibilities, thrust control, and sometimes adjustable nozzles, usually achieve higher efficiency in upper stages and vacuum conditions. In contrast, the main advantages of solid motors are simplicity, rapid readiness, and long-term storability.
For example, if the first stage has 1,100 kN of thrust and four auxiliary boosters each produce 1,100 kN, the total system thrust reaches approximately 5,500 kN. This shows that boosters are used to increase total thrust, and simply mounting motors on boosters does not cause a drop in thrust.
An example of this approach can be seen in the R-7 Semyorka, which used a central core and four side boosters. This design shows that motor performance depends more than anything on matching the nozzle to the operating environment, not on its mounting location.
Consequently, if a sea-level-designed motor with 1,100 kN thrust is mounted on a booster operating in the same atmospheric conditions, its thrust will remain approximately the same. Thrust reduction occurs when the nozzle design is not compatible with the motor’s environmental conditions, not merely because it is a booster motor.
Technical estimates indicate that the thrust of the Simorgh satellite launcher’s first stage is about 1,393 kN; however, for a conservative approach in analyses, we use 1,100 kN. On the other hand, assuming Iran has not yet achieved nuclear warhead miniaturization, the weight of the warhead for a potential intercontinental ballistic missile, similar to first-generation Soviet warheads (R-7 Semyorka), is considered to be about 5 tons.
If we equip the missile with four side boosters (each producing 1,100 kN of thrust), the total thrust at liftoff (including the central stage thrust plus 4 boosters) will reach 5,500 kN. According to aerospace engineering principles, this amount of thrust is entirely sufficient to launch a heavy ballistic missile with a “gross liftoff weight” of approximately 285 tons and can successfully carry a payload including the same 5-ton warhead.
From a scientific perspective, any country that builds a two- or three-stage satellite launcher possesses all the basic technologies for an intercontinental ballistic missile (ICBM), because both share the same principles of propulsion, stage separation, inertial guidance, and aerodynamics.
Iran has demonstrated this capability with launchers such as Qased, Qaem-100, Zuljanah, Simorgh, and Safir. The difference between a satellite launcher and an ICBM lies in the payload (orbital vs. warhead), accuracy (several kilometers vs. hundreds of meters), and operational readiness — all of which are engineering challenges, not scientific barriers. Therefore, converting a satellite launcher into an ICBM is a strategic decision, not a new technological leap.
Inertial Navigation (INS): Accuracy Sufficient for Deterrence
The guidance structure of long-range ballistic missiles consists of three main layers:
Mid-course phase with an Inertial Navigation System (INS) that covers more than 90% of the path. This system is completely independent but has an error of 5 to 10 km over 13,000 km range, which is acceptable for urban targets.
Mid-course correction using astronomical navigation (accuracy 100–300 meters, independent and jam-resistant) or satellite navigation (China’s BeiDou system with several-meter accuracy, but dependent on China).
Terminal phase radar/imaging seeker (50–100 km from target) that achieves accuracy below 10 meters using 3D imaging.
For nuclear deterrence (such as the threat of destroying Washington), the first layer alone with an accuracy of about 2.5 km (CEP) is sufficient — there is no need for pinpoint accuracy.
Farsnews | موشک بالستیک ۱۳۰۰۰ کیلومتری؛ گامی بهسوی موشک اتمی فراقارهای ایران
به روح بلند رهبر شهید، که با بصیرت و ایستادگی در برابر جریانات داخلی فاسد و وابسته، مانع از خلعسلاح ملی و تداوم استقلال دفاعی ایران شد. سامانهی پیشرانش ترکیبی شامل ۴ موتور اصلی ماهوارهبر سیمرغ و ۴ بوستر کمکی (هر یک با ۴ موتور مشابه موتور اصلی) برای افزایش برد موشک بالستیک تا ۱۳٬۰۰۰ کیلومتر...
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