Agni III Test - News & Discussion-3

Vipul · Post by **Vipul** » 24 Apr 2007 20:20

ramana wrote:But this is the Agony thread right?

SSridhar · Post by **SSridhar** » 24 Apr 2007 20:54

Next objective is 5000 Km Agni - Interview by TS Subramanian with Avinash Chander

We thought of Agni-III not as a missile but as a system for the future, with which various configurations can be developed. . . .It had flex [flexible] nozzle control, which no other country had used for the first stage, during the atmospheric phase of the flight. . . . We had to set up our own propulsion plant because there was a total separation of activities between DRDO and ISRO [Indian Space Research Organisation] because ISRO was for totally peaceful uses. We had to build the infrastructure for propellant casting, right from raw material to the actual motor realisation and testing. We did all this in five years. For the motor we have flown now, the raw material came from our captive plants, the motor castings were made at our plant in Chhattisgarh, and we did the static test. . . .The most important point is that with minor modifications in this system we can have the capability for a 5,000-km range, which gives you the strategic depth of deployment so that from within your country you can target any potential threat-areas within this region. That is what gives you the strength. . . .We are now talking of a quantum jump from 3,000 km to 5,000 km range. It will be totally indigenous. We will be adding one more stage within the same dimensions and practically with the same weight. It will be small. We will be doing some weight-saving and adding some. All solid. . . . .The A-3 system is rail-mobile, like A-2. The future 5,000-km-range missile we are planning will be road-mobile. That gives it immunity from vulnerability. The missile system [Agni-III] we are making has state-of-the-art inertial guidance, highly accurate sensors with high immunity from jamming. We have no communication with the ground once we take off. Most of the operations are done in the initial phase except some of the manoeuvres we are planning in the future in order to overcome the interception possibility.
The velocity accuracy we need to achieve at injection is 0.1 metres a second. While the actual velocity of the vehicle is 5,000 metres a second, you should be able to differentiate 5000.1 or 5000.2 metres a second and measure it correctly. That is the type of accuracy required and that is what we have been able to achieve in these systems. . . . . In Agni-III, I can't think of any component that was made in-house. Every component came from the industry. . . . .Range is a question of political requirement. Today, our country is talking of 3,000 km and 5,000 km to meet our... The Chinese have a different need. But as far as our capability is concerned, we have the capability to match the range also. . . . Even though I do not use the same motors, with certain improvements and using the same technology modules I can generate another system, which can take multiple warheads. I can generate a system with a combination of warheads and decoys. Modules of same technology and sizes can be integrated into a system, which can be launched from different kinds of platforms. That is why I said it is a base that we have created, not just a missile. It makes the entire future open.

SSridhar · Post by **SSridhar** » 24 Apr 2007 20:59

Significant Success

sivab · Post by **sivab** » 24 Apr 2007 21:13

SSridhar wrote:Next objective is 5000 Km Agni

This story has lot of technical details. Some of them are very different from Arun's estimates like second stage propellant mass etc.

sivab · Post by **sivab** » 24 Apr 2007 21:24

SSridhar wrote:Significant Success

This story gives flight duration at 13 minutes.

ramana · Post by **ramana** » 24 Apr 2007 21:26

Yeah. Arun_S was basing his on published sources. They are the insiders talking about their design and hence will be more accurate. Arun will update his based on this. BTW its 5km/sec.

The big picture that Arun paints is quite correct- range, payload, missions and future growth potential. In those aspects he is right on the dot.

sivab · Post by **sivab** » 24 Apr 2007 21:27

ramana wrote:Yeah. Arun_S was basing his on published sources. They are the insiders talking about their design and hence will be more accurate. Arun will update his based on this. BTW its 5km/sec.

The big picture that Arun paints is quite correct- range, payload, missions and future growth potential. In those aspects he is right on the dot.

Makes sense. Thanks.

Kumar · Post by **Kumar** » 24 Apr 2007 22:02

Arun_S,

We know a lot about Indian missile capabilities thanks to your good work.

What is lacking as of now is a good comparison of Indian missiles with those in the extended neighborhood. That analysis will be very helpful in informing people where India stands wrt others in the neighborhood and beyond.

Currently the missle info in public domain basically regurgitates the official statements/claims. Official Paki reports on their missiles are always superlative. Official Indian reports are always diminutive. A good independent technical analysis of main Indian, Paki, Chini, Russian and American missiles will be very valuable IMHO.

sanjaykumar · Post by **sanjaykumar** » 25 Apr 2007 02:40

It had flex [flexible] nozzle control, which no other country had used for the first stage, during the atmospheric phase of the flight.

Most interesting: This can only be to defeat boost-phase missile defences. This along with an assumption of MIRV throwweight means they are planning for inflicting horrible destruction if they need to launch- a convincing deterrent strategy.

Lalmohan · Post by **Lalmohan** » 25 Apr 2007 03:01

do we know if dragon is developing any anti-missile defences?

gashish · Post by **gashish** » 25 Apr 2007 04:48

From Shri Avinash Chander's interview:

The velocity accuracy we need to achieve at injection is 0.1 metres a second. While the actual velocity of the vehicle is 5,000 metres a second, you should be able to differentiate 5000.1 or 5000.2 metres a second and measure it correctly. That is the type of accuracy required and that is what we have been able to achieve in these systems.

The teeth we are talking of is that it is a totally indigenous system, indigenously designed and indigenously produced, leaving aside some electronic components...

these electronic components as per my guess would be MEMs sensors and high-performance Data converter ICs (A/D, D/A)..resolution of 0.1 m/s when speeds can be higher than 5000 m/sec is a very demanding application...highly accurate converters with atleast 16 bits of resolution required!...some IC design houses in India already have started designing such cicruits.......inshallah...the day will not be far when india will be self-sufficent in converters space as well

but not really sure where MEMs development stand in india though....one of the known names in this area Paulraj Arogyaswami (heard his name on BR years ago) has a company in India....
the challenge in MEMs is just not designing of circuits..but also the foundry process technology....most ICs can be manufactured at pure-play foreign foundries like TSMC,UMC etc.....but MEMs would require the design house to have its own foundry too!!

ramana · Post by **ramana** » 25 Apr 2007 09:55

x-posted from the Agni update sticky

thammu
BRFite -Trainee
Quote:
Hi junta,

It is nice to see some mails here. (I know, I don't post actively, but
still.. Smile Recently I have been to Wheeler island, some 10km off the
coast at Dhamra, Orissa.

url

I was there during the launch of Agni-III. About nine months earlier,
there had been a test flight of Agni-III, the first ever. However, the
maiden flight encountered problems a minute after lift off and was not
entirely successful in meeting the mission objectives. From whatever
data was available, we were able to determine the reason for failure.
It turns out from the CFD simulation that I have carried out during the
post flight analysis that during the initial ascent phase of the
missile, the external freestream air interacts with the hot rocket
exhaust of the first stage rocket motor and creates a pocket of
recirculating hot gases just behind the vehicle. Agni-III uses a
flexible nozzle for thrust vector control. In order to allow the nozzle
to deflect, an annular gap was left between the nozzle and the
cylindrical shell of the missile instead of closing it entirely. It was
through this gap that the recirculating hot gases entered the portion
of the missile (called base shroud) and caused damage to the electronic
components present there.

It took us nearly two months of extensive analysis, CFD simulation from
my side and simulation of the flight electronics by other teams, to
establish this phenomenon as the cause of failure. It took another six
months to design a flexible barrier which would protect the base shroud
from the hot gases while simultaneously allowing the nozzle to flex.
Again from several CFD simulations, I was able to provide the thermal
and pressure loads which the thermal barrier would experience and thus
should be designed to withstand. Another month for launch preperations and we were ready for launch on 12th April.

The four minutes on 12th April, were undoubtedly among the most
exciting moments of my career at DRDO. Four minutes during which our
entire efforts are put to test. Four minutes because it corresponds to
the powered phase of the flight during which all flight events
including separation of the expended stages take place. Beyond that,
good old gravity takes over Smile We were in a building about 1km from the
launch pad from where we could feel the noise and vibration from a
thrust of hundred tons. The flight video and the trajectory were
projected in real time. The sky was fabulously clear and visibility was
great. The cameras were able to track the missile more than a hundred
kilometres. It was even possible to make out in the flight video when
the first stage separation occurred.

Thirteen minutes from lift-off and it was all over. The round of
applause that followed would probably have drowned the noise during
lift-off Smile It was one of the most thrilling and professionally
satisfying moments of my life and one which I would cherish for a long
time to come.

Cheers,
Rajki

Neshant · Post by **Neshant** » 25 Apr 2007 10:06

Wow. That is truly inspirational.

vinayak_d · Post by **vinayak_d** » 25 Apr 2007 10:15

Hmmm a lot of reports keep harping on 13 mins duration of flight. How does this along with 400 km apogee and 9 ton fuel for second stage fit in with Arun's or ROCKETSIM calculation?

gashish · Post by **gashish** » 25 Apr 2007 10:18

A big THANK YOU to Rajki..The Nation is grateful for your great service.

Austin · Post by **Austin** » 25 Apr 2007 10:35

The A-3 system is rail-mobile, like A-2. The future 5,000-km-range missile we are planning will be road-mobile.

Emm So A-3 and A-2 would be limited to Rail Mobile only.

The 3 Stage Road mobile A-4 would probably be a wodden round. They would probably do away with vented interstage of1.1 m, Add a 1.1 m 3rd stage , that would probably also introduce some interesting Cold Launch technique like the way they launch brahmos

Kudos to T.S. Subramanian for this excellent interview

Arun_S · Post by **Arun_S** » 25 Apr 2007 12:00

What do you guys make of of the figures being quoted:

1.) India Today article shows re-entry velocity of 4.5Km/sec where as Front line interview Shri Avinash Chander says 5km/sec.

2) Both articles report launch weight of 47.3 tonnes, but Shri Avinash Chander says first stage fuel was 30 tonnes(so stage mass of 33 tonne), and second stage fuel of 9 tonne (mass of ~10.3 tonne) add payload mass of 1.5 tonnes and total becomes 34.8 tonne. There is unaccounted difference of 2.5 tonne mass . (BTW if second stage is 10 tonne the 3rd stage is very likely to weight ~3 tonne)

Can someone help try to reconcile this?

BTW form comparative analysis of density I knew that second stage will likely carry 9 tonne fuel, but there was no way I can total up launch mass to 47.3 tonne unless I assumed the second stage is as dense as first stage and used some new dense fuel material (M51 uses a special dense fuel).

But once we can figure out the 2.5 tonnes discrepancy in item 2 above, that will clear the air a lot.

Cheers

ramana · Post by **ramana** » 25 Apr 2007 19:35

Does any one have the graphic from Inida Today on the AIII test?

Austin · Post by **Austin** » 25 Apr 2007 20:03

ramana wrote:Does any one have the graphic from Inida Today on the AIII test?

Ramana check mail

ramana · Post by **ramana** » 25 Apr 2007 20:14

I did. I was wondering if only the graphic is available. Would make super screen saver !

Austin · Post by **Austin** » 25 Apr 2007 20:45

ramana wrote:I did. I was wondering if only the graphic is available. Would make super screen saver !

Aha , Unless some one can scan that earlier , I can deliver it by Friday

Shankar · Post by **Shankar** » 25 Apr 2007 22:02

Minuteman-III MIRV launch sequence:
1. The missile launches out of its silo by firing its 1st stage boost motor (A).
2. About 60 seconds after launch, the 1st stage drops off and the 2nd stage motor (B) ignites. The missile shroud is ejected.
3. About 120 seconds after launch, the 3rd stage motor (C) ignites and separates from the 2nd stage.
4. About 180 seconds after launch, 3rd stage thrust terminates and the Post-Boost Vehicle (D) separates from the rocket.
5. The Post-Boost Vehicle maneuvers itself and prepares for re-entry vehicle (RV) deployment.
6. The RVs, as well as decoys and chaff, are deployed during backaway.
7. The RVs and chaff re-enter the atmosphere at high speeds and are armed in flight.
8. The nuclear warheads detonate, either as air bursts or ground bursts.

Code: Select all

The four minutes on 12th April, were undoubtedly among the most
exciting moments of my career at DRDO. Four minutes during which our
entire efforts are put to test. Four minutes because it corresponds to
the powered phase of the flight during which all flight events
including separation of the expended stages take place

In minuteman 3 the second stage ognites after 120 secs pr two minutes and 3rd stage separates after 180 secs

compared to this agni3 2nd stage seperation is stated to be after 4 minutes?

Rentry velocity minuteman 3 rv is 7.1 km/sec agni 3 is 5 km/sec?

And the mass discrepancy of 2.5 to 3 tons

well well there is more tp agni 3 than we know as of now

Shankar · Post by **Shankar** » 25 Apr 2007 22:11

Altitudes Where ICBM
is in Powered Flight
(200 to 300 seconds)

http://www.carnegieendowment.org/pdf/np ... -01(3).pdf

However another flight profile analysis the powered flight lasts between 200-300 seconds (5 minutes max 3 min 20 sec s minimum

Agni 3 flew for 4 minutes
=240 seconds

more or less the exact mid point

well the conclusion is not very clear at least at this stage?

ShibaPJ · Post by **ShibaPJ** » 25 Apr 2007 22:18

Can the weight difference of ~2.5 to 3 tons be ascribed to a new, denser fuel type? (Unless a much higher payload was tested, of course).

Shankar · Post by **Shankar** » 26 Apr 2007 00:34

my guess it was a higher payload -that will make depressed trajectory flight and relatively lower RV velocity easily achievable easily the without much difficulty and easiest way to fool the world since no one will know the RV weight and consequently the achievable range of agni 3.

The flight time also points to this option being used -comparatively longer flight duration (powered phase) -lower apogee-lower range ,you take of the added wt -more range ??

Arun_S · Post by **Arun_S** » 26 Apr 2007 01:58

SSridhar wrote:Significant Success

This is another TS Subramanian's mine of information:

Quoting in full:

Significant success

"Before the jubilation," said Avinash Chander, Programme Director, Agni-III, "there were times we had heart attacks." The countdown for the launch had progressed smoothly. The long-range ballistic missile lifted off at 10.52 a.m. on April 12 from its rail-mobile launcher on Wheeler Island in the Bay of Bengal, 9 km from Dhamra on the Orissa coast. Optical radar stations at Dhamra, Chandipur-on-sea near Balasore in Orissa, Port Blair, and on two ships stationed in the Bay of Bengal, were tracking the missile.

As the Agni-III project team scanned the computer screens at the Mission Control Centre on Wheeler Island, they were horrified by the data loss reported from some of the radar stations. "The moment there is data loss, the first thing that comes to mind is that something [disastrous] has happened," said Avinash Chander, who is the Director of the Advanced Systems Limited, Hyderabad, which designed and developed the missile. It was another 70 seconds before the team breathed again and felt confident about the success of the mission.

What happened was this: as the missile climbed, its plume of jet exhaust blocked the radio signals (telemetry) from the vehicle to the ground stations resulting in attenuation of the signals.

After the missile's first stage fired for about 80 seconds, the second stage ignited and then the first stage jettisoned. The second stage burned for about 100 seconds before it broke away. During those 100 seconds, the missile's path was in a guided phase. In other words, its course was modified to reach the target. The warhead (dummy payload) then travelled with fine velocity control, re-entered the earth's atmosphere at the right altitude withstanding a searing temperature of 4,000Â°Celsius and fell in the Bay of Bengal. The flight duration: 13 minutes.

At Wheeler Island the splashdown was greeted with applause and elation by the Agni-III team, including Avinash Chander; Dr. V.G. Sekaran, Project Director; D.P. Rao, Director, Integration; B. Sankara Rao, Director, Composite Products Development Centre, Advanced Systems Laboratory, Hyderabad; and Tessy Thomas, Associate Project Director. Among the others present were M. Natarajan, Scientific Adviser to the Defence Minister, V.K. Saraswat, Chief Controller (Missiles and Strategic Systems), Defence Research and Development Organisation; and Prahalada, Chief Controller, R&D, DRDO (Services Interaction).

Agni-III is a two-stage, indigenously built long-range missile that weighs 48.3 tonnes and is 16.7 metres long. It has a diameter of two metres and can carry nuclear warheads weighing 1.5 tonnes over a distance of 3,500 km.

Natarajan called it a "significant success, particularly when the entire design, planning, material construction, execution and everything associated with the mission was indigenous". The hardware, software, instrumentation and tracking stations were indigenously built. The success was sweeter because it came after the failure of the maiden flight of Agni-III on July 9, 2006. "We wanted to demonstrate our success with our product, not by shooting our mouths off," said Dr. Sekaran.

About 258 industries in the public and private sectors were partners in the Agni-III mission.

T.S. Subramanian

Other reports have confirmed First Stage burn time of 85 seconds and second stage of 105 seconds. Burn time is not a big IF issue right now.

Vick · Post by **Vick** » 26 Apr 2007 05:38

ArunS, not sure if someone has already mentioned this or not but your A3 diagrams show the A3 to be 16.3m in length while this article states 16.7m.

Also, would you mind explaining to this dolt how the A3 1st stage can be 7.7m long and burn for 80s but the 2nd stage, at 3.1m in length, burn for 100s? Does the 2nd stage use slower burning prop?

Lastly, if you don't mind me asking, not that I don't appreciate the effort but any chance of the BR Space section getting a spruce up?

Raj Malhotra · Post by **Raj Malhotra** » 26 Apr 2007 09:42

Arun_S wrote:What do you guys make of of the figures being quoted:

1.) India Today article shows re-entry velocity of 4.5Km/sec where as Front line interview Shri Avinash Chander says 5km/sec.

2) Both articles report launch weight of 47.3 tonnes, but Shri Avinash Chander says first stage fuel was 30 tonnes(so stage mass of 33 tonne), and second stage fuel of 9 tonne (mass of ~10.3 tonne) add payload mass of 1.5 tonnes and total becomes 34.8 tonne. There is unaccounted difference of 2.5 tonne mass . (BTW if second stage is 10 tonne the 3rd stage is very likely to weight ~3 tonne)

Can someone help try to reconcile this?

BTW form comparative analysis of density I knew that second stage will likely carry 9 tonne fuel, but there was no way I can total up launch mass to 47.3 tonne unless I assumed the second stage is as dense as first stage and used some new dense fuel material (M51 uses a special dense fuel).

But once we can figure out the 2.5 tonnes discrepancy in item 2 above, that will clear the air a lot.

Cheers

Can it be that the motor casing is heavier than calculated here? I think Today article seems to indicate it is marging steel and not composite

ramana · Post by **ramana** » 26 Apr 2007 10:08

If they said regular steel than it could be as you say. Maraging steel has high strength same as composite and thus should be similar mass fraction. BTW has anyone thought why they use maraging steel when they already have composite for F/S?

Shankar · Post by **Shankar** » 26 Apr 2007 11:31

After the missile's first stage fired for about 80 seconds, the second stage ignited and then the first stage jettisoned. The second stage burned for about 100 seconds before it broke away. During those 100 seconds, the missile's path was in a guided phase. In other words, its course was modified to reach the target. The warhead (dummy payload) then travelled with fine velocity control, re-entered the earth's atmosphere at the right altitude withstanding a searing temperature of 4,000Â°Celsius and fell in the Bay of Bengal. The flight duration: 13 minutes.

Code: Select all

Minuteman-III MIRV launch sequence:
1. The missile launches out of its silo by firing its 1st stage boost motor (A).
2. About 60 seconds after launch, the 1st stage drops off and the 2nd stage motor (Cool ignites. The missile shroud is ejected.
3. About 120 seconds after launch, the 3rd stage motor (C) ignites and separates from the 2nd stage.

The four minutes on 12th April, were undoubtedly among the most
exciting moments of my career at DRDO. Four minutes during which our
entire efforts are put to test. Four minutes because it corresponds to
the powered phase of the flight during which all flight events
including separation of the expended stages take place

merlin · Post by **merlin** » 26 Apr 2007 11:41

BTW has anyone thought why they use maraging steel when they already have composite for F/S?

Is maraging steel stronger than composite? Second stage could be using a different composition of fuel that needs higher strength casing, maybe that's the reason?

Arun_S · Post by **Arun_S** » 26 Apr 2007 11:53

Hardened against radiation based ABM !

Arun_S · Post by **Arun_S** » 26 Apr 2007 12:04

Vick wrote:ArunS, not sure if someone has already mentioned this or not but your A3 diagrams show the A3 to be 16.3m in length while this article states 16.7m.

Yes there is a discrepancy, but a small one (I have been keeping v busy, so I did not think the error i ssignificant enough).

Also, would you mind explaining to this dolt how the A3 1st stage can be 7.7m long and burn for 80s but the 2nd stage, at 3.1m in length, burn for 100s? Does the 2nd stage use slower burning prop?

Yes slower burning. That allows higher efficiency and higher ISP. The nozzle is set deep inside thus carries lesser fuel for given overall volume. The slow burn also helps keeps the acceleration to acceptable level for lighter payload configuration, that is crucial for INS accuracy.

Lastly, if you don't mind me asking, not that I don't appreciate the effort but any chance of the BR Space section getting a spruce up?

Yes sir I hear it, but I am going to be more busy next 3 months, after that things will start to turn around. Thanks for pointing it out and for your patience.

Austin · Post by **Austin** » 26 Apr 2007 14:00

India Spreads Nuclear Wings

Kumar · Post by **Kumar** » 27 Apr 2007 06:10

dinesha · Post by **dinesha** » 30 Apr 2007 12:52

[quote]India Draws Confidence From Agni-3 Test Flight
By VIVEK RAGHUVANSHI, NEW DELHI
http://www.defensenews.com/story.php?F= ... &C=asiapac

The April 12 test firing of an Agni-3 ballistic missile has bolstered Indiaâ€™s confidence that it can develop an intercontinental ballistic missile, scientists said.
The chief of the Defence Research and Development Organisation (DRDO), M. Natarajan, told a press conference here April 15 that it would require just â€œthree yearsâ€

JCage · Post by **JCage** » 30 Apr 2007 14:27

Saran Singh, associate professor at Jawarharlal Nehru Universityâ€™s School of International Studies here, also admits that Pakistan is ahead of India in missile capabilities.

Rahul Bhonsle, a defense analyst here and retired Army brigadier. â€œWhile the capabilities of the DRDO should have [improved] considerably from the early 1990s, the technology involved is much more complex, hence it is not envisaged that the Agni-3 missile will be operational before 2015 or so.â€

negi · Post by **negi** » 30 Apr 2007 14:52

[quote]Rahul Bhonsle, a defense analyst here and retired Army brigadier. â€œWhile the capabilities of the DRDO should have [improved] considerably from the early 1990s, the technology involved is much more complex, hence it is not envisaged that the Agni-3 missile will be operational before 2015 or so.â€

rakall · Post by **rakall** » 30 Apr 2007 15:09

Saran Singh, associate professor at Jawarharlal Nehru Universityâ€™s School of International Studies here, also admits that Pakistan is ahead of India in missile capabilities.

Yes.. and LTTE airforce is better than IAF too..

Rahul Bhonsle, a defense analyst here and retired Army brigadier. â€œWhile the capabilities of the DRDO should have [improved] considerably from the early 1990s, the technology involved is much more complex, hence it is not envisaged that the Agni-3 missile will be operational before 2015 or so.â€

Amitabh · Post by **Amitabh** » 30 Apr 2007 18:17

[quote="JCage"][quote]Rahul Bhonsle, a defense analyst here and retired Army brigadier. â€œWhile the capabilities of the DRDO should have [improved] considerably from the early 1990s, the technology involved is much more complex, hence it is not envisaged that the Agni-3 missile will be operational before 2015 or so.â€