Beg to disagree.. A4 is a completely new missile with the composite second stage and a larger first stage.. It has nothing to do with the original A2, none of the two stages are common. The guidance package is also different with the indigenous ring laser gyro and GNSS guidance.. The only thing that is common could be the TEL and the RV.dinesh_kimar wrote:^ The missile program used the technology available at the time.A2 was already in service, and based on SLV3 with existing supply chain , so A4 building blocks were in place and could be quickly realized. My speculation is that its easy for DRDO to produce and launch A4, so we have maximum launches and SFC tests using this type. There was a long lead time for making 2m diameter maraging steel casings for A3, and those big heavy solid motors.Realization of Each subsystem was a seperate project. Its a complicated system.
Indian Missiles News & Discussions - May 2017
Re: Indian Missiles News and Discussions - May 2017
Re: Indian Missiles News and Discussions - May 2017
WHich company has the capability to design and develop a TEL like that in India? It will require substantial investment of time and money to get that capability. If there is a critical need for off-road capable TEL's it may be worthwhile to make the investment. For now the road-mobile TELs are enough.Jits wrote:
Why can't we have a TEL like this. The weight and dimensions of TOPOL M are almost similar to Agni V (except the stated range)
Re: Indian Missiles News and Discussions - May 2017
@haridas: is'nt the conical motor in A-5 inherently optimum for a single warhead payload and inefficient for MIRV payloads ?
Re: Indian Missiles News and Discussions - May 2017
Having a composite 1st stage for the Agni 4 is a BIG DEAL. They were struggling to make such huge structures before.
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Re: Indian Missiles News and Discussions - May 2017
Indranil ji, didnt we use composites in K4 / K15 missiles already?Indranil wrote:Having a composite 1st stage for the Agni 4 is a BIG DEAL. They were struggling to make such huge structures before.
Re: Indian Missiles News and Discussions - May 2017
That is correct.ramdas wrote:@haridas: is'nt the conical motor in A-5 inherently optimum for a single warhead payload and inefficient for MIRV payloads ?
However it has some significant advances that could be incorporated in MIRV configuration too. E.g short stage length due to recessed rocket cone.
Last edited by Haridas on 27 Jan 2018 13:34, edited 1 time in total.
Re: Indian Missiles News and Discussions - May 2017
Saar, iirc it would be worth searching initial reports (first 1.5 yrs) on Agni 3 motor casing for first & second stage. You might be surprised. As you know A4 came about much later than the 2 m dia A3.Indranil wrote:Having a composite 1st stage for the Agni 4 is a BIG DEAL. They were struggling to make such huge structures before.
I recall a photo ~2006 of Tessy Thomas inaugurating the arrival of first A4 booster motor, well before she became director of A4 program.
Re: Indian Missiles News and Discussions - May 2017
IIRC from old discussion A4 has 1.8m first stage booster composite and A-3/A-5 is 2m 1st stage composite meter
Re: Indian Missiles News and Discussions - May 2017
Yes. But the booster casing was not composite. My memory could be failing me here, but I think this is the first time that they have used composite casing for the booster in the Agni series.Haridas wrote:Saar, iirc it would be worth searching initial reports (first 1.5 yrs) on Agni 3 motor casing for first & second stage. You might be surprised. As you know A4 came about much later than the 2 m dia A3.Indranil wrote:Having a composite 1st stage for the Agni 4 is a BIG DEAL. They were struggling to make such huge structures before.
I recall a photo ~2006 of Tessy Thomas inaugurating the arrival of first A4 booster motor, well before she became director of A4 program.
Re: Indian Missiles News and Discussions - May 2017
I know that they are trying the NEPE based propellants too. Would that be the last technological frontier that we need to master for the solid motors.
Re: Indian Missiles News and Discussions - May 2017
From most reports, Agni-IP was to be first missile with composite booster and NEPE based propellant. Agni-IV was the first to have a composite second stage. Now, A-V has the same. Agni-IV all composite is a big step forward.
NEPE based propellant will be the next stage. I think they have already used it for the Pinaka-MKII rockets and plan was to use it was Agni-IP missile. By the way I think the A-IP will also be a completely new missile just like the A-IV as compared to the old A-II.
The bigger question for India's strategic missile program is always the size of the petals. Do we have a 500 Kg 200-275 Kt warhead or not is the mystery.
For A-IP we can optimize the missile with a 350-400 Kg 150 Kt warhead and a 1,500 Km range. That takes care of all of pak for us, with a small and highly road mobile canisterized missile.
An all composite A-IV will take care of China for a single warhead profile and will have a range of about 5K for a 500-800 Kg 200-350 Kt warhead.
A-V will need a composite first stage and MIRV to realize its true potential and be our equivalent of Topol-M and DF-41.
NEPE based propellant will be the next stage. I think they have already used it for the Pinaka-MKII rockets and plan was to use it was Agni-IP missile. By the way I think the A-IP will also be a completely new missile just like the A-IV as compared to the old A-II.
The bigger question for India's strategic missile program is always the size of the petals. Do we have a 500 Kg 200-275 Kt warhead or not is the mystery.
For A-IP we can optimize the missile with a 350-400 Kg 150 Kt warhead and a 1,500 Km range. That takes care of all of pak for us, with a small and highly road mobile canisterized missile.
An all composite A-IV will take care of China for a single warhead profile and will have a range of about 5K for a 500-800 Kg 200-350 Kt warhead.
A-V will need a composite first stage and MIRV to realize its true potential and be our equivalent of Topol-M and DF-41.
Re: Indian Missiles News and Discussions - May 2017
Other than the radars, is there a need to spend forex on the missile units? a supposed DRDO strengthWhat is the S-400? The S-400 is a mobile, surface-to-air missile system that shoots down incoming aerial threats such as aircraft, drones, and cruise and ballistic missiles. It has been designed to offer a layered defence using four different missiles – the very long range 40N6E-series (400 km), the long range 48N6 (250 km), the 9m96e2 (120 km) and the short range 9m96e (40 km). With a tracking range of 600 km, the missile system can engage up to 36 targets simultaneously within a range of 400 km and an altitude of up to 185 km. The US Patriot missile defence system, in comparison, supports only one interceptor missile within a range of 96 km. The 9m96e2 missile is the jewel of the system. Flying at Mach 15 and manoeuvring up to 20g, the missile is capable of engaging targets as low as five metres off the ground. It can knock out penetrating aircraft and cruise missiles that may be flying just above the ground to avoid detection by radars. But there is more. The S-400 system comes with optional acquisition radars (such as 59N6 Protivnik GE and 67N6 Gamma DE in the L-band, the 1L119 Nebo SVU in the VHF band, and the multiband Nebo M), which have been designed to track down modern stealth aircraft. Moreover, the system’s jamming-resistant radars and ability to track a large number of targets make it more effective against drone swarms than other missile defence systems in use
idrw.org .Read more at India No 1 Defence News Website http://idrw.org/how-indias-new-russian- ... qus_thread .
Re: Indian Missiles News and Discussions - May 2017
Indranil is right, A4 had the second stage as the composit. The second stage motors are much smaller motors compared to the first stage. In fact, the A4s second stage was the first composite motor to be tested. A5 uses the A3 first stage and replaces the second stage maraging steel motor with a composite motor. Dollar for dollar, having the upper stages as composite makes a much bigger difference to the throw weight than the first stage.
I really like the way the A3-A5 program was managed, taking bite sized technical problems and solving them iteratively. The A3 solved the flex nozzles, the A5 brought in the composite second stage and eliminated the ugly interstage. At every stage of the program, technical risk was kept low and the iterative product delivered in reasonable amount of time.
I really like the way the A3-A5 program was managed, taking bite sized technical problems and solving them iteratively. The A3 solved the flex nozzles, the A5 brought in the composite second stage and eliminated the ugly interstage. At every stage of the program, technical risk was kept low and the iterative product delivered in reasonable amount of time.
Re: Indian Missiles News and Discussions - May 2017
What do you think is the issue?mody wrote:The bigger question for India's strategic missile program is always the size of the petals.
You mean Indian missiles petals dont carry the computer simulated TN weapons per maha-mahim Dr R Chidambram ?
Re: Indian Missiles News and Discussions - May 2017
Wouldnt a composite first stage help make it faster overall in boost phase?
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Re: Indian Missiles News and Discussions - May 2017
Reduction of first stage weight reduces the overall weight and/or increases range or throw weight. The lower stage always has a higher mass fraction compared to the upper stages. Decreasing its weight/making it more efficent will allow a higher fuel capacity and leadto a better staging and will increase range or throw weight.
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Re: Indian Missiles News and Discussions - May 2017
The efficiency of the rocket stage will be related to the ratio of total weight/ burn out weight so keeping the lower burn out weight low will increase the efficiency of that stage. There are optimization equations developed for determining the best weight ratios of each stage for a given set of parameters in multistage rockets.
Re: Indian Missiles News and Discussions - May 2017
I think there could be many variants of composites developed over period of time that might offer better fuel mass fractions , The Composites Woven in mid-80 for Agni-2RV wont be the same as they might be doing in 2015.
Re: Indian Missiles News and Discussions - May 2017
Austin ji, my chaiwalla's saala said the A3 booster was composite and (low and behold ) the upper stage was maraging. Very conphusing conter intutive when the first test flight took place. Recall the clear hi res pic of the first launch (failed) that you saw near VT.
Re: Indian Missiles News and Discussions - May 2017
True , I recollect the discussion but A-3 was a new system on which A-5 and other variant was developed 2 m dia and new High Beta BGRV , it was virtually new system in all aspects including guidance and computer etc so using maraging steel was to minimise risk.Haridas wrote:Austin ji, my chaiwalla's saala said the A3 booster was composite and (low and behold ) the upper stage was maraging. Very conphusing conter intutive when the first test flight took place. Recall the clear hi res pic of the first launch (failed) that you saw near VT.
If I recollect from memory even Booster for GSLV has moved to all composite which are larger dia motor compared to A-3/5 series.
My point was since 1985 when they developed first carbon composite RV , I am sure they must have moved to better high strength low weight composite
Re: Indian Missiles News and Discussions - May 2017
DRDO And NAL Collaborate On A New Small Turbojet For UCAV Applications
Interesting that RCI is speaheading this project. If we get this working in double quick time, we could build our own SCALP/JASSMER/Storm Shadow equivalent with an LO frame at a fraction of the cost of imports and hence build in large numbers. And of course loitering munition/uav vehicles that can be airlaunched with an LO frame. Crossed fingers!While the flagship fighter-class ‘Kaveri’ low-bypass turbofan engine program being developed by DRDO’s Gas Turbine Research Establishment (GTRE) is some distance away from delivering flyable examples, a few small jet engine development efforts are currently underway by entities looking to power unmanned aerial systems (UAS) being developed by them. The latest among them being the small gas turbine jet engine (SGTJE) collaborative project by DRDO’s Research Centre Imarat (RCI), Hyderabad and the Propulsion Division of the National Aerospace Laboratories (NAL), Bengaluru.
SGTJE is envisaged to be a 275 kgf producing turbojet that according to RCI will power an ‘unmanned combat aerial vehicle’ or UCAV.
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Re: Indian Missiles News and Discussions - May 2017
wrt carbon fiber production
Saurav Jha
@SJha1618
5h5 hours ago
And in really good news for indigenization, note that MIDHANI is setting up an integrated carbon fiber plant which will also have a 100 ton per year aerospace grade carbon fiber prepeg line using technology from NAL.
Saurav Jha
@SJha1618
5h5 hours ago
And in really good news for indigenization, note that MIDHANI is setting up an integrated carbon fiber plant which will also have a 100 ton per year aerospace grade carbon fiber prepeg line using technology from NAL.
Re: Indian Missiles News and Discussions - May 2017
Can anyone produce one Agni III image with the first stage appears to be composite? I Couldnt find any. The progression was:
Agni III (all maraging steel, not sure about the conical stage)
Agni IV (First stage maraging steel, Second stage composite)
Angi V (First stage maraging steel, second stage composite, conical stage composite, interstage eliminated).
Agni III (all maraging steel, not sure about the conical stage)
Agni IV (First stage maraging steel, Second stage composite)
Angi V (First stage maraging steel, second stage composite, conical stage composite, interstage eliminated).
Re: Indian Missiles News and Discussions - May 2017
Austin How do A3 and A5 have high beta?
Beta=W/A*CD. Units are weight per unit ref area.
Those heavy payloads will gave lower beta than A2 which has lower CD.
So the sentence should say higher beta.
Beta=W/A*CD. Units are weight per unit ref area.
Those heavy payloads will gave lower beta than A2 which has lower CD.
So the sentence should say higher beta.
Re: Indian Missiles News and Discussions - May 2017
I will wait too. I am pretty sure one can't. I remember the talk given by Dr. Saraswat at IIT-Bombay. He specifically said Agni V has composite casings for the 2nd and 3rd stages. Agni V and Agni II have the same booster. Agni VI has the same three stages as Agni V, except its first stage has a composite case. The throw weight increases from 1 ton to 3 ton. Agni VI and its SLBM version will be MIRV capable. The SLBM version will also have three stages (all composites), will be fatter and stouter and will sport a spike for drag reduction.sudeepj wrote:Can anyone produce one Agni III image with the first stage appears to be composite? I Couldnt find any. The progression was:
Agni III (all maraging steel, not sure about the conical stage)
Agni IV (First stage maraging steel, Second stage composite)
Angi V (First stage maraging steel, second stage composite, conical stage composite, interstage eliminated).
Simultaneously, Tessy Thomas said that Agni III has now been (or being) optimized to 22 tons. Somebody had provided a link to the company that makes the trailers for Agni missiles. The categories where sub-15, ton sub-25 ton, sub-50 ton (which was also marked as Agni-V) and sub-65 tons, So connect the dots.
AFAIK, Agni IV will be our first ballistic missile to sport a composite case for the 1st stage (I don't know about the K series). But eventually all our missiles will Agi-1 is becoming Agni-1P, Agni-3 is becoming Agni-3P (22 tons), Agni V is becoming Agni VI.
I don't think I have anything more to add to this.
Re: Indian Missiles News and Discussions - May 2017
If the flight time is 1000 secs, then it is not an UCAV. It is a loitering munition which weighs about 700-800 kgs and the range is going to be about 250-350 kms.Prasad wrote:DRDO And NAL Collaborate On A New Small Turbojet For UCAV ApplicationsInteresting that RCI is speaheading this project. If we get this working in double quick time, we could build our own SCALP/JASSMER/Storm Shadow equivalent with an LO frame at a fraction of the cost of imports and hence build in large numbers. And of course loitering munition/uav vehicles that can be airlaunched with an LO frame. Crossed fingers!While the flagship fighter-class ‘Kaveri’ low-bypass turbofan engine program being developed by DRDO’s Gas Turbine Research Establishment (GTRE) is some distance away from delivering flyable examples, a few small jet engine development efforts are currently underway by entities looking to power unmanned aerial systems (UAS) being developed by them. The latest among them being the small gas turbine jet engine (SGTJE) collaborative project by DRDO’s Research Centre Imarat (RCI), Hyderabad and the Propulsion Division of the National Aerospace Laboratories (NAL), Bengaluru.
SGTJE is envisaged to be a 275 kgf producing turbojet that according to RCI will power an ‘unmanned combat aerial vehicle’ or UCAV.
Re: Indian Missiles News and Discussions - May 2017
^^ You are implying the military munition airframe to have a Lift to drag ratio of just 2.9 (=800/275). That ratio IMHO should be about 5 - 8 (depending on maneuvering required) to get an idea of the size/potency of the craft.
Re: Indian Missiles News and Discussions - May 2017
My number is indeed conservative. But, I am assuming that full thrust is not required in ideal cruise condition.
Re: Indian Missiles News and Discussions - May 2017
Sorry sir I will have to take you to the mat.
Really ? Wrong !Indranil wrote:Agni V and Agni II have the same booster.
wow the composite stage casing must be generating thust (using unobtainium), or is a wishful thinking with no scientific fesibility/foundation.Agni VI has the same three stages as Agni V, except its first stage has a composite case. The throw weight increases from 1 ton to 3 ton.
She is a scientist & engineer and would speak in measured way within a context, but surely who listened and reported it must be a dumb dork media reporter, for it is impossible to transform 48 tonne solid fuel missile throw capabelity (even assuming maraging case) into a 22 tonne solid fuelled craft no matter the level of optimization. I would be happy to be proven wrong (and eat vegitarian crow equivalent) if someone can kindly show scintifically / mathamatically it's viability using earthly material, much less material and techniques that isro or drdo has demonstrated.Simultaneously, Tessy Thomas said that Agni III has now been (or being) optimized to 22 tons.
Re: Indian Missiles News and Discussions - May 2017
If rated thrust is X at SL, at typical cruise altitude you can take cruise thrust to be 0.25X. Max thrust at that altitude would be only a little higher than that.Indranil wrote:My number is indeed conservative. But, I am assuming that full thrust is not required in ideal cruise condition.
Re: Indian Missiles News and Discussions - May 2017
I have always doubted that last part too (though said it here on BRF). 48 to 22 seems just to good to be true in real life.Haridas wrote:Sorry sir I will have to take you to the mat.Really ? Wrong !Indranil wrote:Agni V and Agni II have the same booster.wow the composite stage casing must be generating thust (using unobtainium), or is a wishful thinking with no scientific fesibility/foundation.Agni VI has the same three stages as Agni V, except its first stage has a composite case. The throw weight increases from 1 ton to 3 ton.She is a scientist & engineer and would speak in measured way within a context, but surely who listened and reported it must be a dumb dork media reporter, for it is impossible to transform 48 tonne solid fuel missile throw capabelity (even assuming maraging case) into a 22 tonne solid fuelled craft no matter the level of optimization. I would be happy to be proven wrong (and eat vegitarian crow equivalent) if someone can kindly show scintifically / mathamatically it's viability using earthly material, much less material and techniques that isro or drdo has demonstrated.Simultaneously, Tessy Thomas said that Agni III has now been (or being) optimized to 22 tons.
Re: Indian Missiles News and Discussions - May 2017
Have to agree with Haridas on the wt. savings part. The realistic wt. savings from metallic to composite conversion is around 15-20% (at least in aerospace applications). For parts/structures which do not have details could see up to 35-40% of weight savings but most parts/structures IRL do have details which would limit the amount of weight savings.
Probably the number is a mistake made by reporter...
Probably the number is a mistake made by reporter...
Re: Indian Missiles News and Discussions - May 2017
Haridas, you are wrong and Indranil is right. Agni3 weight indeed has been reduced to 22T primarily using composites. Agni4 is a new generation missile (compared to earlier Agni series) with new technologies apart from reduction in weight. These technologies are finding their way into newer missiles.
Re: Indian Missiles News and Discussions - May 2017
You will find the info about weight reduction of Agni3 below. Also the new Agni3 has new technologies. I am not sure if there were improvements in propellant.
http://www.xinhuanet.com/english/2017-0 ... 240453.htm
http://www.xinhuanet.com/english/2017-0 ... 240453.htm
Re: Indian Missiles News and Discussions - May 2017
Moving to composite, along with the weight savings provides more strength.
This allows for using higher pressure propellants. So higher thrust, helps in throw weight and range.
This allows for using higher pressure propellants. So higher thrust, helps in throw weight and range.
Re: Indian Missiles News and Discussions - May 2017
As I said earlier that number is conservative. WE are probably looking at 1000-1200 kgs, or even more if it is going to be air launched.JayS wrote:If rated thrust is X at SL, at typical cruise altitude you can take cruise thrust to be 0.25X. Max thrust at that altitude would be only a little higher than that.Indranil wrote:My number is indeed conservative. But, I am assuming that full thrust is not required in ideal cruise condition.
Re: Indian Missiles News and Discussions - May 2017
Yes, most likely better propellants have been used but I am unable to get references.
Re: Indian Missiles News and Discussions - May 2017
With due respect sir, I don't mind being taken to the mat with proper logic and reasoning. But what you say makes no sense to me at the moment.Haridas wrote:Sorry sir I will have to take you to the mat.
Isn't the typo obvious there. I meant Agni III.Haridas wrote:
Really ? Wrong !
If you make the upper stage lighter, it has a remarkable effect on the size of the booster required. Case in point: By making the second stage lighter, Agni 2P has twice the range of Agni 2 using similar sized boosters even for the same payload. The missiles' overall weights are 16 and 17 tons respectively.Haridas wrote:wow the composite stage casing must be generating thust (using unobtainium), or is a wishful thinking with no scientific fesibility/foundation.Agni VI has the same three stages as Agni V, except its first stage has a composite case. The throw weight increases from 1 ton to 3 ton.
While I am not completely right in making the bolded statements above (more on that later), the following are slides from Dr. Saraswat.The payload increases from 1 ton to 3 ton with only a marginal increase in weight. Notice that he highlights that all three stages are made out of composites. Agni VI will actually have a new first stage which weighs 40 tons. The diameter will be slightly larger (presumably 2.3 mtrs) than that of the A5. While revealing this in 2013, Dr. Chander also said it is a technological challenge that the country has to overcome, i.e. to build a composite booster.
It was not one reporter who reported, but a few.Haridas wrote: She is a scientist & engineer and would speak in measured way within a context, but surely who listened and reported it must be a dumb dork media reporter, for it is impossible to transform 48 tonne solid fuel missile throw capabelity (even assuming maraging case) into a 22 tonne solid fuelled craft no matter the level of optimization. I would be happy to be proven wrong (and eat vegitarian crow equivalent) if someone can kindly show scintifically / mathamatically it's viability using earthly material, much less material and techniques that isro or drdo has demonstrated.
She said they completely redesigned Agni III, just like they are doing for Agni 1 now. In the new Agni 3, the upper stage has a composite casing. It has new lighter avionics and has single digit accuracy. Hence, they decreased the payload from 2.5 tons to 1.5 tons. Even Avinash Chander spoke of the reduction of the payload. Now, if they dropped 2 tons or so from the second stage and made it much more efficient, how big does the booster need to be. Another way to ask the question is if it takes 16 tonnes for Agni IV to lob 1 ton to 4000 kms, how many tons does it need to lob 1.5 tons to similar distance. Suddenly, the 22 tons seems plausible, doesn't it?
On the other hand, you are asking me to believe that the guys always had the technology to build the motor casing of the booster using composites, but not the upper stages. So, in Agni III, they used composites for the lower stage and maraging steel for the upper stages. And then they went to Agni V wherein they discarded the composite casing from Agni III and started using a steel casing again. How does this stand your sanity test?