Multiple Independent Targetable Re-entry Vehicle (MIRV)
US is a nation is preoccupied with its national interests and priorities more than any country on this planet, and this singular protocol seems to have inspired China, to robust emulation. As a mark of its new found power status the Chinese seem to be everywhere in and around the Asia-Pacific region. This crusade of belligerence and posturing is redefining standard foreign policies processes of many countries, specifically India, Japan, South Korea, Taiwan, Philippines and Vietnam who seem to have certain levels of niggling region. China's has been progressively increasing its defense budget vis-a-vis development of sophisticated weapons and defense related equipment over the last few decades. The result is China has introduced an appalling assortment of arms of sundry magnitude, China is also on the cusp of deploying Multiple Independent Re-entry Vehicle (MIRV) on their ballistic missiles, a development that is likely to have profound and pervasive outcome for the region and beyond.
What is a MIRV?
US Minuteman III MIRV ICBM launch sequence: 1. The missile launches out of its silo by firing its first-stage boost motor (A). 2. About 60 seconds after launch, the 1st stage drops off and the second-stage motor (B) ignites. The missile shroud (E) is ejected. 3. About 120 seconds after launch, the third-stage motor (C) ignites and separates from the 2nd stage. 4. About 180 seconds after launch, third-stage thrust terminates and the post-boost vehicle (D) separates from the rocket. 5. The post-boost vehicle maneuvers itself and prepares for reentry vehicle (RV) deployment. 6. While the post-boost vehicle backs away, the RVs, decoys, and chaff are deployed (this may occur during ascent). 7. The RVs and chaff reenter the atmosphere at high speeds and are armed in flight. 8. The nuclear warheads detonate, either as air bursts or ground bursts.
The US during the whetting era of cold war developed a uniquely dangerous weapon able to strike anywhere in the Soviet Union at wanton. The missile an MIRV also carried decoys and chaffs to evade air defense systems. This new technology undermined the entire balance of power between the two superpowers and struck fear into hard hearts of Soviet citizens.
The military purpose of a MIRV:
- Provides greater target damage for a given missile payload.
- A multiple independently targetable reentry vehicle (MIRV) warhead is a collection of nuclear weapons carried on a single intercontinental ballistic missile (ICBM) or a submarine-launched ballistic missile (SLBM). Using a MIRV warhead, a single launch can strike several targets, or fewer targets redundantly.
- With single warhead missiles, one missile must be launched for each target. By contrast with a MIRV warhead, the post-boost stage can dispense the warheads against multiple targets across a wider area. Theoretically at least, only a small portion of an adversary’s missile force would be necessary to completely eliminate one’s strategic deterrent.
- MIRV is destabilizing force primarily because they give nations greater confidence to destroy the enemy's critical missile sites in a first strike action by launching multiple, lower yield warheads.
- Reduces the effectiveness of an anti-ballistic missile system that relies on intercepting individual warheads. Thus, in both a military and economic sense, MIRVs render ABM systems less effective, as the costs of maintaining a workable defense against MIRVs would greatly increase, requiring multiple defensive missiles for each offensive one.
- Decoy reentry vehicles can be used alongside actual warheads to minimize the chances of the actual warheads being intercepted before they reach their targets.
Why India needs MIRVs?
Agni-5 is capable of launching 4-5 multiple warheads, whose yield is unknown. Although it is not clear if the government has gone ahead and cleared the developed of MIRV system, former head of India’s DRDO, V.K. Saraswat, noted that several Agni variants could eventually be developed with this capability. Development of MIRV technology is vital to India's National Security because of potential threats from hostile adversaries, besides it will strengthen its aspirations of a complete nuclear triad and lastly it compliments India's minimum nuclear deterrence policy. Pakistan’s aggressive postures and China’s belligerence toward India in the recent past necessitates such an indispensable step. The deployment of MIRV technology will quantifying India's nuclear deterrence and enhance defence preparedness
Can India develop the Technologies involved?
The building blocks from boosters to radars, seekers and sophisticated mission control centers are currently available. DRDO had been able to develop key Radio Frequency seeker technologies for missiles, it has since indigenously perfected this technology, and digital processing during the missile's boost, mid-course and terminal phase is based on DRDO’s own software. The RF and Infra Red seekers are meant for proximity and precision engagement of targets, and both these technologies are required for the anti-ballistic missile (ABM) capability apart from other missiles as well. India is working on a new seeker technology with other countries also. Today, India is able to design and develop RF seekers, and in about a year or so, it will be independent in this key technology. Coming years would see greater Indian investment in micro-electro mechanical systems (MEMS), nano-sensors, nano-materials and advanced information technology tools. Such advancements would be essential for creating reliable, robust and highly accurate systems like the MIRV. This technology would enhance India’s nuclear deterrence capabilities.
Cutting-Edge Techs
Weapon Dispersion
Analyzing a ballistic trajectory is a simple physics problem, but there is big difference betweem analysis and implementation. Recording the necessary data, rapidly analyzing it, combined with ever changing variables, to determine the precise moment to release a warhead so that it hits a specific target 8-10 thousand miles away, is not a simple task. Therefore, dispersing nuclear warheads is another major technological challenge.
China developed a method for deploying multiple satellites under a contract with Motorola. The deployment method utilized a "smart dispenser" to place Iridium class communication satellites into orbit and the know-how was transferred from Lockheed Martin Corporation. Another auxiliary technology required is the availability of expendable perigee/apogee kick motors, these are small booster motors set to lift satellites into higher orbits.
However, India had developed both these technologies locally much before the Chinese cloned it. The PSLV-C20 launch in February 2013 is very significant because for the first time 7 satellites were inserted into their precise orbits using an embedded System-on-Chip (SOC) method, and the same SOC methodology is used for Agni-5 to assist its accuracy during its guidance and terminal phases. A notable point is that ISRO and DRDO have tested this key MIRV prerequisite by stealth which had clear military implications.
Miniaturization
Miniaturization of nuclear and thermonuclear weapons as has been obtained to fit the nose cone spatial shape of Agni missiles. Weapons design and testing has to be simulated in a virtual environment using Super Computers since actual testing stands frozen after Pokhran-II. It must be assumed that BARC scientists have achieved the level of miniaturization deemed adequate and suitable 20 KT fission warhead.
Re-entry Design
All missile launch planning begins with a set of requirements that has to be met to achieve mission objectives. The re-entry phase of a mission is no different. There is a very delicately balance of three, often competing, requirements:
- Deceleration
- Heating
- Accuracy of landing or impact
Modern ballistic trajectory nuclear weapon system delivery vehicles typically utilize slender sphere-cone geometries with multiple warheads on a single delivery bus. For a given warhead and associated arming device, the designer selects the re-entry vehicle base diameter and vehicle length, which effectively determines the cone half-angle. The nose bluntness ratio is then selected based on drag and heat transfer considerations. The delivery vehicle has to sustain high high aerodynamic stress (deceleration) and heating, hence it must be made of advance materials. Although the agencies have worked extensively on aero-thermal structure and thermal protection system designs over the past decade for both its space and missile programs, its effective use on MIRV platform is yet to be ascertained.
Other prerequisites
- Robust guidance and control computers with adequate computational abilities to conduct complex maths
- Develop advanced and accurate inertial guidance systems such as gyroscope and accelerometers for precise and decisive targeting.
Conclusion
It is evident from history that there exists a close concurrence between space and missile programs as was the case with both the Soviet Union and America. China and India have also pursued the same path. The interchangeability of several technologies between the two entities suit there sustained development, but the more pronounced beneficiary is undeniably the missile program. Though the Indian missile program has matured to world-class levels, it is mastering some of the above technologies that will make MIRV integration as a holistic deterrent system.
by Admin