Agni & Prithvi Ballistic Missiles : News & Discussions

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India test-fires nuclear-capable ICBM Agni-V - Times of India

NEW DELHI: India on Thursday morning test-fired its Agni-V intercontinental ballistic missile (ICBM) in its final operational configuration from the Abdul Kalam Island off the Odisha coast, taking another step forward toward its eventual induction into the Strategic Forces Command (SFC).

There was no immediate word on whether the first "user-trial" of the nuclear-capable Agni-V missile, which can even reach the northern-most parts of China with its strike range of over 5,000-km, had met all the parameters laid down for the test.
 

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Successful Pre-induction Trial of India’s Agni-V Intercontinental Ballistic Missile Takes It Closer To Deployment


Earlier today, the Agni-V Intercontinental Ballistic Missile (ICBM) developed by the Defence Research and Development Organization (DRDO) successfully underwent what is being called a ‘pre-induction trial’, a sort of user assisted trial, that has taken it closer to deployment with India’s Strategic Forces Command (SFC), which is the ‘user’ in question. This launch was also the third successful launch in-a-row from a canisterized road-mobile launcher. Moreover, this test-flight seems to indicate that residual problems with the Agni-V’s primary battery supplying on-board electrical power have also been resolved.



The development of the Agni-V Intercontinental Ballistic Missile (ICBM) certainly marks the arrival of India as a missile power. With a range of ‘easily more than 5,500 km’, the Agni-V clearly confers upon India the ability to hold all of China’s Eastern Seaboard cities at risk from Peninsular India. But then, there is more to this missile than its range capability. In technological terms, this missile represents the coming of age for India of a very long range payload delivery capability that is both rather accurate as well as survivable. Let us take a closer look, at some of the Agni-Vs technological features of significance.



Guidance

The missile has a contemporary guidance package that utilizes an indigenous ring laser gyroscope based inertial navigation system (RLG-INS) developed by DRDO’s Research Center Imarat (RCI) in Hyderabad. For redundancy it also has a micro-electromechanical systems (MEMS)- based inertial measurement unit (IMU) that has also been developed by RCI.

Both the RLG-INS and MEMS-IMU are capable of receiving multi-constellation updates from satellite navigation systems such as the American GPS and the Russian GLONASS as well as India’s satellite based augmentation system, GAGAN, to remove accumulated errors in their measurements.

The superior accuracy of the Agni V can also be attributed to the incorporation of a system on chip (SOC) based on-board computer (OBC) that weighs just 200 grams and boasts 6-7 times greater processor capability than legacy printed-circuit board (PCB) based systems which could weigh up to 5 kgs. This SOC-OBC has robust communication interfaces such as a three-channel bus etc and runs on fault-tolerant software. The embedded SOC concept used for both guidance and control requires very little power and gives far greater leeway in warhead configuration besides enhancing efficiency.



Use of Composites

Agni-V is not just more accurate but is also more reliable and indeed survivable. While its 2.0-m-diameter, first stage motor is made of 250 grade maraging steel, its second and third stages have carbon fiber reinforced polymer (CFRP) casings.The second stage also has a diameter of 2.0 m. The total burn time for all three stages together is estimated to be close to four minutes.

The use of CFRP stages facilitates greater fuel fraction, enhancing range capability. In the future, even the first stage of Agni-V will use carbon composite motor casings and that would take care of the issue of corrosion altogether and enhance overall structural integrity. The Agni-V also relies on digitally connected multi-channel communications within its body for the control system, thereby reducing a lot of the cabling that would have otherwise gone into such missiles. This serves to reduce the risk of failure in the missile system and increases dependability.

This features have all been validated in today’s launch, which was the fifth consecutive successful test of this missile overall. The use of corrosion-resistant composites and digital connectivity within the missile makes it easier to turn the Agni-V into a classic ‘wooden round’ – that is a canisterised missile system transportable by road and rail ready to launch on demand, with an almost maintenance free stowage and storage life of 10 years or so.


Cold launch scheme

Agni-V in canisterised configuration consists of a mission ready missile, a gas generator for ejecting the missile out of the canister to a height of about 30 metres at which point the Stage-I motor ignites, and the missile speeds towards its target. This cold launch scheme allows the missile to be launched from relatively unprepared strips. Work on a steam-gas missile ejection system is currently underway for the Agni-V and canisterized ballistic missiles.

The missile canister itself sits on the Agni-V’s Transport-cum-Tilting vehicle-5 (TCT-5), designed and developed by DRDO’s Vehicle Research and Development Establishment, Ahmednagar.

The Agni-V itself is 17 metres long and has a launch weight of about 50 tonnes with a 1.5 tonne payload which is adequate to carry fusion boosted fission warheads with a yield of 200-300 kilotonnes.



Survivability against emerging anti-ballistic missile threats

Now, while an Agni-V locked and loaded sitting in a canister somewhere in India is not exactly what China likes to hear first thing in the morning, the middle kingdom could actually have more to worry about. The Agni-V’s re-entry vehicle shown in previously released pictures may turn out to be rather manoeuvrable making things difficult for emerging Chinese terminal anti-ballistic missile (ABM) defences. All three stages of the Agni-V in any case have flex nozzle control systems which enhance manoeuvrability during flight.



The future?

One more ‘user assisted trial’ by SFC and DRDO will be done before the Agni-V is considered moves into the early deployment with future trials being dubbed ‘user training exercises’. It may also serve as a baseline for a longer ranged and heavier missile that will carry multiple independently targetable re-entry vehicles (MIRV) and this missile may be designated Agni-VI. Despite, the Agni-V’s current potency, a MIRV Agni-VI will be needed to guarantee penetration against China’s ABM system in the decades ahead.

At the moment, the Project Director for Agni-V is G. Ramaguru whereas director of the overall Agni Programme is MRM Babu. Both of whom, along with Dr Sateesh Reddy, who is currently Scientific Adviser to the Indian Defence Minister and Director General, Missile and Strategic Systems were present for this morning’s Agni-V launch.
 
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We are long way from MIRV...... But the good thing is we are moving in the right direction..... A step at time, Unlike our neighbor
 
USA miuteman missile is a single warhead missile without any GPS navigation but merely inertial guidance system. The logic behind it is that in war, GPS signals will be blocked by jammers. Worse, it can even be spoofed. So, if there is no GPS, it is impossible to spoof it and hence maintain great accuracy.

The concept of MIRV is about having multiple missiles in the second/third stage instead which is then targeted to different locations. Such targeting doesn't ensure higher chance of hit but just lowers the number of missiles required. The saturation effect doesn't come by MIRV as it hits different targets and hence different BMD is targeting different warheads. To get saturation effect, the system used in MRV where multiple warhead strikes the same area but at a distance. Since all warheads are falling on same area, it acts like a cluster bomb and hence increased saturation. Unfortunately, this MRV is easy to make and is available even with Pakistan.

MIRV is only useful when one wants to strike maximum number of targets with constraints over number of missiles. The BMD can reload after it intercepts these incoming issiles at different areas and hence saturation effect doesn't come. MIRV is mainly useful in submarine missiles.
 
USA miuteman missile is a single warhead missile without any GPS navigation but merely inertial guidance system. The logic behind it is that in war, GPS signals will be blocked by jammers. Worse, it can even be spoofed. So, if there is no GPS, it is impossible to spoof it and hence maintain great accuracy.
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Minuteman-III LGM-30 was and still is a 3-MIRV'ed ICBM

Restriction was placed earlier due to the START-II treaty but was never operationalized, which was later replaced by follow-on agreements such as SORT and New START, which do not limit MIRV capability.

Presently the LGM-30G armed with 3x Mk-21/W87 RVs from the deactivated Peacekeepers under the SERV program.


A GPS-based system is not central to the missile's guidance but to decrease guidance errors and can be used to identify inflight guidance anomalies post which corrective measure can be taken by the missile itself. It gives the guidance system a fail-safe option. In the case of India, we use G3OM chips that compare US, Russian and Indian navigational signals to compile an even more accurate positional data to aid in navigation.

GPS is even more indispensable when you mate MaRV to ICBM as the US is planning to do for their Trident missiles. India already operates MaRV hence the need for GPS-based guidance.

The saturation effect doesn't come by MIRV as it hits different targets and hence different BMD is targeting different warheads.

Ofcourse it does, especially if the victim country lacks a credible exo-atmospheric intercept capability. The MIRVs separate during the initial re-entry phase and every BMD system tracks a huge area of space. Even if the MIRVs target locations far from each other, the same system has to intercept all of them. So, it ultimately comes down to the number of interceptors you have at your disposal. More MIRVs, less interceptors per MIRV, higher the chance for the warhead to hit its target.

The BMD can reload after it intercepts these incoming issiles at different areas and hence saturation effect doesn't come.

I don't think you understand what a saturation attack is.
 
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Ofcourse it does, especially if the victim country lacks a credible exo-atmospheric intercept capability. The MIRVs separate during the initial re-entry phase and every BMD system tracks a huge area of space. Even if the MIRVs target locations far from each other, the same system has to intercept all of them. So, it ultimately comes down to the number of interceptors you have at your disposal. More MIRVs, less interceptors per MIRV, higher the chance for the warhead to hit its target.

I don't think you understand what a saturation attack is.
You are mistaking MIRV for MRV. MIRV is separated much before re-entry and is capable of targeting different cities like Karachi and Gwadar. In the second stage itself, the missiles will separate after using common first stage to go in different ballistic trajectory. MRV on the other hand separates on reentry and strikes different parts of the same city like striking Mumbai in Worli, Thane, Powai etc. In this case, it will be saturation attack.

PS: MIRV and MRV are different. MaRV is the type of warhead (maneuverable). MRV and MIRV are types of warhead attachment, not the warhead themselves. MRV and MIRV can use MaRV warheads too
 
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You are mistaking MIRV for MRV. MIRV is separated much before re-entry and is capable of targeting different cities like Karachi and Gwadar. In the second stage itself, the missiles will separate after using common first stage to go in different ballistic trajectory. MRV on the other hand separates on reentry and strikes different parts of the same city like striking Mumbai in Worli, Thane, Powai etc. In this case, it will be saturation attack.

PS: MIRV and MRV are different. MaRV is the type of warhead (maneuverable). MRV and MIRV are types of warhead attachment, not the warhead themselves. MRV and MIRV can use MaRV warheads too

Im not confusing the two. Even with MIRVs, it is possible to saturate a BMD system.

The first layer of defense or the exo-atmospheric interceptors are usually located close to the border giving them enough time to intercept the warhead before entering the atmosphere. This can be explained with the example of intercepting MRVs below point 7 as shown in the pic.

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The second layer of defense or endo-atmospheric interceptors are located close to major targets so that the warheads can be intercepted at lower altitudes, below point 8. The warheads remain close together making it relatively easier for missile shield to track an intercept them

Meanwhile, MIRVs enter the atmosphere from different directions making it harder for the exo-interceptors to track/chase and kill them. Also, multiple MIRVs launched from multiple BMs, targetting the same city is even more hard to kill and need more interceptors to take down all of them once it enters the atmosphere, especially at different times and from different directions.

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Im not confusing the two. Even with MIRVs, it is possible to saturate a BMD system.

The first layer of defense or the exo-atmospheric interceptors are usually located close to the border giving them enough time to intercept the warhead before entering the atmosphere. This can be explained with the example of intercepting MRVs below point 7 as shown in the pic.

pociski_batalistyczne-660.jpeg


The second layer of defense or endo-atmospheric interceptors are located close to major targets so that the warheads can be intercepted at lower altitudes, below point 8. The warheads remain close together making it relatively easier for missile shield to track an intercept them

Meanwhile, MIRVs enter the atmosphere from different directions making it harder for the exo-interceptors to track/chase and kill them. Also, multiple MIRVs launched from multiple BMs, targetting the same city is even more hard to kill and need more interceptors to take down all of them once it enters the atmosphere, especially at different times and from different directions.

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Ypu are absolutely correct if the discussion is about exoatmosphere interceptors. They will be badly saturated by MIRV. But, as far as I know, very few exo atmospheric BMD are operational and have a reasonable interception rate. Most BMD available are untested against exo atmospheric interception, even S400. Our PDV also can only intercept slow moving Prithvi missiles and not fast ones. So, the reentry interception is something that requires more weightage.

The reentry BMD can't be saturated by multiple MIRV as the time difference allows for reloading of missiles into BMD. Reloading prevents saturation
 
The saturation effect doesn't come by MIRV as it hits different targets and hence different BMD is targeting different warheads.
First, you said it is not possible to saturate BMD with MIRV
They will be badly saturated by MIRV. But, as far as I know, very few exo atmospheric BMD are operational and have a reasonable interception rate.
Then you said they'll be "badly saturated". And by your own response, if an exo-atmospheric interceptor has a low interception rate, that mean there is a higher chance that the BMD can be saturated with comparatively less number of warheads!

Make up your mind.

The BMD can reload after it intercepts these incoming issiles at different areas and hence saturation effect doesn't come.

It takes a THAAD launcher around one hour or so to reload its canisters. Are you telling me that an aggressor will wait till then to launch the next volley?
https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiQtcb-t-LYAhVCJMAKHQCgAFIQFggpMAA&url=https://www.38north.org/wp-content/uploads/pdf/2016-03-10_THAAD-What-It-Can-and-Cant-Do.pdf&usg=AOvVaw3eg3XuiLvTzkKpqHa_fJqP

Our BMD system is yet to demonstrate an "operational" TEL carrying multiple interceptors that can be easily deployed. Then we'll talk about reloading in the field.

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BTW, S-400 has limited BMD capability, that too endo-atmospheric.
 
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First, you said it is not possible to saturate BMD with MIRV

Then you said they'll be "badly saturated". And by your own response, if an exo-atmospheric interceptor has a low interception rate, that mean there is a higher chance that the BMD can be saturated with comparatively less number of warheads!

Make up your mind.



It takes a THAAD launcher around one hour or so to reload its canisters. Are you telling me that an aggressor will wait till then to launch the next volley?
https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiQtcb-t-LYAhVCJMAKHQCgAFIQFggpMAA&url=https://www.38north.org/wp-content/uploads/pdf/2016-03-10_THAAD-What-It-Can-and-Cant-Do.pdf&usg=AOvVaw3eg3XuiLvTzkKpqHa_fJqP

Our BMD system is yet to demonstrate an "operational" TEL carrying multiple interceptors that can be easily deployed. Then we'll talk about reloading in the field.

58b72fb7d2ab9.image.jpg


BTW, S-400 has limited BMD capability, that too endo-atmospheric.


I was only considering endo-atmospheric BMD. I don't have any hopes for exo-atmospheric BMD as I consider these to be highly unreliable and meaningless, at least as of now. So, I have a firm mind regarding this. It is simply that I have just discarded exo-atmospheric interceptor as mere fantasy.

The reload time can be reduced by tweaking. What is the reload time for Patriot missile?
 
I was only considering endo-atmospheric BMD. I don't have any hopes for exo-atmospheric BMD as I consider these to be highly unreliable and meaningless, at least as of now. So, I have a firm mind regarding this. It is simply that I have just discarded exo-atmospheric interceptor as mere fantasy.

The reload time can be reduced by tweaking. What is the reload time for Patriot missile?

Just because you don't have hopes, doesn't mean countries are going to stop developing high altitude HTK interceptors.
As of now, every operational BMD system is susceptible to saturation attacks by salvo launched MIRV mounted BMs.

Even a PAC-3 launcher reload can take anywhere between 45 to 60 mins.

"Doctrinally, a crew has 60 minutes to conduct a full missile reload on one launcher, using either a crane or a forklift," said Capt. Brendan McIntyre, 1-43 ADA Battery commander.
Patriot Missile Soldiers maintain, train to isolate air threats > U.S. Air Forces Central Command > Display
 
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