Indian Missiles News and Discussions - May 2017

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Re: Indian Missiles News and Discussions - May 2017

Postby JTull » 31 Jan 2018 21:22

http://ajaishukla.blogspot.ch/2013/05/advanced-agni-6-missile-with-multiple.html

The Agni-5 is a three-stage, solid-fuel missile but its first stage consists of a metallic rocket motor, while the second and third stages have composite motors.


Chander says the Agni-6 will carry a massive three-tonne warhead, thrice the weight of the one-tonne warhead that Agni missiles have carried so far. This will allow each Agni-6 missile to launch several nuclear warheads --- Multiple Independently Targetable Re-entry Warheads (MIRVs) --- with each warhead striking a different target. Each warhead --- called Maneuverable Reentry Vehicle (MARV) --- performs evasive maneuvers while hurtling down towards its target, confusing enemy air defence missiles that are trying to destroy them mid-air.


“Our ballistic missiles must be compact and road mobile, even the Agni-6 with its heavy payload. We will do this by building the first stage with composites, fitting the Agni-6 with India’s first composite 40-tonne rocket motor. This is a technical challenge but we have good capability in lightweight composites,” says Chander.

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Re: Indian Missiles News and Discussions - May 2017

Postby JTull » 31 Jan 2018 21:26

http://ajaishukla.blogspot.ch/2016/12/agni-6-icbm-evolving-organically-from.html

Currently, the Agni-5 has a metallic first stage, made of “maraging steel”, while the second and third stages are entirely built from lightweight composites, which were first tested in the Agni-4 on 15 Nov 2011. Stage-1 components like high-temperature rocket motor nozzles are already being made of composites. Gradually, the Agni-5 could become an all-composite missile that is significantly lighter than at present.

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Re: Indian Missiles News and Discussions - May 2017

Postby JTull » 31 Jan 2018 21:27

http://ajaishukla.blogspot.ch/2016/12/cutting-edge-agni-technologies-to-add.html

The Agni-1P will be a two-stage, solid propellant missile. Both stages will have composite rocket motors, guidance systems with electro-mechanical actuators, and inertial navigation systems based on advanced ring-laser gyroscopes.


By the time the DRDO built the Agni-4 in 2011, it had successfully developed composite rocket motors, high-energy propellants, electro-mechanical actuators and navigation systems with ring-laser gyros that can navigate a ballistic missile to a target thousands of miles away, striking it within a few hundred metres.

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Re: Indian Missiles News and Discussions - May 2017

Postby JTull » 31 Jan 2018 21:29

http://ajaishukla.blogspot.ch/2012/04/no-intention-to-cap-missile-programme.html

The Agni-5 has three stages, with the second and third stage built of composite materials. The next missile will have a composite first stage as well, making it lighter and, therefore, able to carry a heavier payload than the 1.5 tonne payload of the current Agni-5.

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Re: Indian Missiles News and Discussions - May 2017

Postby Singha » 31 Jan 2018 21:44

The a6 does away with conical third stage and slide shows a full diameter meaty motor below the ogival nose

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Re: Indian Missiles News and Discussions - May 2017

Postby sudeepj » 31 Jan 2018 21:52

Agni III weight simply cant be reduced from 48 tonnes to 22.. That will be a completely new missile (new motors, new structures, new TEL, new canister..) , which the scientists may still be calling Agni III because its range is 3xxx kms.

As long as it delivers the bumb and the maga-bumb, who am I to complain? They can call it whatever they want.. :rotfl:

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Re: Indian Missiles News and Discussions - May 2017

Postby Singha » 31 Jan 2018 22:04

It will be the definitive agni2 ... fatter but shorter with higher throw weight

Agni3 is a evolutionary dead end i doubt any are in active service with sfc

Agni1 , agni2mk2 and agni5/6 will be pur long term play like trident and minuteman3

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 01 Feb 2018 01:51

IR trade studies depend on exigencies.
Which technology for which vehicle is to bring it to field fastest.

Composite first stage is quite complex.
The insulating liner over which the filament is wound and then cure the chamber and then pour such a large fuel mixture. And then radiography to ensure no defects.
The filament has to be GE as pressures are high.
So a program plan would make that the last milestone.

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 01 Feb 2018 01:52

Singha wrote:The a6 does away with conical third stage and slide shows a full diameter meaty motor below the ogival nose



Conical stage was special for A5. It adds range and corrects velocity error.

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Re: Indian Missiles News and Discussions - May 2017

Postby Indranil » 01 Feb 2018 02:05

ramana wrote:IR trade studies depend on exigencies.
Which technology for which vehicle is to bring it to field fastest.

Composite first stage is quite complex.
The insulating liner over which the filament is wound and then cure the chamber and then pour such a large fuel mixture. And then radiography to ensure no defects.
The filament has to be GE as pressures are high.
So a program plan would make that the last milestone.

We both would be in agreement then. The counterpoint being presented is that A3 had composite casing for booster, and second stage was made out of maraging steel!!!!

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 01 Feb 2018 07:01

From Wiki page on AGNI III



The Agni-III features two solid fuelled stages and with overall diameter of 2.0 meters. This diameter is compatible with a recently tested Indian sub-surface launch system, which has a 2.3 meter diameter launch tube aperture.

The first stage booster is made of advanced carbon composite materials to provide high payload fraction (mass fraction). It is 7.7 meters long, with a diameter of 2 metres. The second stage made of maraging steel and has a length of 3.3 metres. The second stage has vectoring nozzles, to provide necessary flight trajectory control.


I don't know why this was. If First stage is composite and is more difficult, why go back for second stage?

Unless it was already developed for some reason.

Which program has a 2 meter diameter and 3.3 meter length motor made from managing steel?

Or maybe they originally planned this second stage motor with maraging steel.and did not revise it even after achieving the composite first stage?

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 01 Feb 2018 09:36

I think there is an error. The first stage was maraging steel. The change to composites has been a steady affair and outdated pieces of information have been jumbled. The first stage of Agni5 is also maraging steel but expect that to be changed too.

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Re: Indian Missiles News and Discussions - May 2017

Postby Indranil » 01 Feb 2018 10:27

Yes. The following statements cannot be true.

1. We had the tech to build a composite casing for the booster but not so for the upper stage of much smaller size and thrust.
2. The designers of Agni 3 did not know the relative advantage of having a composite booster vs having a composite second stage.
3. Agni 3 and Agni 5 have boosters of the same size. Agni is a successful design. And yet, the designers of Agni 5 went back to maraging steel for Agni 5.

I can't fathom how somebody as knowledgeable as Haridas ji can believe in a hypothesis for which the above statements have to hold true.

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Re: Indian Missiles News and Discussions - May 2017

Postby JayS » 01 Feb 2018 10:50

Indranil wrote:
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.

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.


Was just saying. With 800kg and 275kgf we are looking at cruise L/D of (800/275)*4 = ~12

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Re: Indian Missiles News and Discussions - May 2017

Postby Haridas » 01 Feb 2018 12:09

Indranil ji, I am out of pocket due to work pressure next few days to rebutt and evolve the discussion. Please bear with me. Thanks.

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Re: Indian Missiles News and Discussions - May 2017

Postby Haridas » 01 Feb 2018 12:17

Supratik wrote: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.

I bow to you saar, you must be right. Let me humbly learn from your judgement, but I find so little specific knowledge/data/insight in your post to glean from your wisdom.

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Re: Indian Missiles News and Discussions - May 2017

Postby Haridas » 01 Feb 2018 12:35

JayS wrote:
Indranil wrote:My number is indeed conservative. But, I am assuming that full thrust is not required in ideal cruise condition.


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.

What would be a reasonable assumption for cruising altitude of the cruise missile?
Any insight on jet intake design for given cruising altitude and how (for a given engine core) the optimum intake changes depending on design cruising altitude (hope the question itself leads to an insight). I am trying to understand how the 0.25 factor is arrived at.

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Re: Indian Missiles News and Discussions - May 2017

Postby Philip » 01 Feb 2018 12:54

A piece on BMos development to 800KM.The bit about BMos-NG on Tejas while seeming a great development if poss.,to my mind is burdening that little fighter with too many jobs to do. Our med. seized aircraft,M2Ks,29-UGs and Rafales to come ,if able to carry an NG under-fuselage ,would be sufficient in launching strikes deep into enemy territory.while MKIs would be able to carry 3.Tejas should instead be armed with shorter ranged PGMs and long-range AAMs/Astra,to augment its air combat interceptor capabilities,which was the main role of the MIG-21s which it is replacing.Trying to turn it into an "Asterix" high on some magic potion,would be a mistake.Moreover,the cost of BMos missiles whatever variant will be expensive and the inventory with the IAF would be limited and used against the main enemy targets/bases first.Tejas equipped with bomb kits for "dumb bombs" and other PGM missiles and perhaps the glide bomb too,would be a good assortment of stand-off munitions given its limitations in air combat compared to heavier fighters armed with larger numbers of BVR and WVR AAMs.

http://www.defencenews.in/article/The-m ... ile-526161
The making of an 800-km range Brahmos Supersonic Missile
Thursday, February 01, 2018
By: Army Recognition

The BrahMos Aerospace company will develop a new variant of the BRAHMOS missile with a range of up to 800 km, according to the Hindustan Times newspaper. According to the official catalogue of the BrahMos Aerospace company, the original variant has a firing range of up to 290 km in accordance with the stipulations placed by the Missile Technology Control Regime (MTCR) that limits the range of export-oriented missile weapons to less than 300 km.

"India is laying the groundwork to test a high-range BrahMos supersonic cruise missile, capable of striking targets more than 800 km away," the daily says, citing unnamed sources. The newspaper adds that the missile might be tested before the year-end.

In February 2017, S. Cristopher, Director of India's Defence Research and Development Organisation (DROD) told Indian media that the range of the BRAHMOS missile would be extended to 450 km and then to 800 km. The variants of the extended range BRAHMOS variants would be available for ground-, sea- and air-based platforms, he added. The official pointed out that the modification of the missile with a range of 800 km would be developed within next two years. However, the development schedule seems to have been shrunk. As a result, in March 2017, India successfully tested the BRAHMOS-ER (Extended Range) missile that had a range of 400 km. According to the Hindustan Times newspaper, the missile is now being reconfigured in order to achieve the goal, namely, to increase its range to 800 km.

The modernization of the BRAHMOS missile to 800 km will beef up the capabilities of the Indian military in a drastic manner. "It [the new variant of the BRAHMOS] will be a significant leap forward for the BrahMos project. [The Indian] Air Force fighters will be able to attack targets from increased standoff ranges," an Indian official told the Hindustan Times daily.

BrahMos Aerospace also pays a special attention to the development of the air-launched variant of the BRAHMOS designated BRAHMOS-A. The BRAHMOS-A is an air-launched cruise missile (ALCM) intended for Sukhoi Su-30MKI (NATO reporting name: Flanker-H) fighter jets of the Indian Air Force (IAF). A Su-30MKI of the IAF successfully test-fired the ALCM in November 2017. "The successful maiden test-firing of the BRAHMOS ALCM from the Su-30MKI will significantly bolster the IAF's air combat operations capability from stand-off ranges," India's Ministry of Defense (MoD) said in a statement.

It should be mentioned that the Indian military has revealed an intention to develop a lightened variant of the BRAHMOS-A ALCM designated BRAHMOS-NG (New Generation). According to the Hindustan Times newspaper, the BRAHMOS-NG is currently at the design stage, and initial consultations have already been held. The new ALCM will be integrated with the indigenous Tejas LCA (Light Combat Aircraft) air platform. The BRAHMOS-NG is planned to be developed by 2019.

The IAF is reported to have placed orders worth approximately USD650 million for the BRAHMOS-A. The service expects to get a total of approximately 40 Su-30MKI multirole fighter jets modified for the ALCM. Each aircraft will be able to carry a single BRAHMOS-A missile.

The Hindustan Times says that the Indian military is planning to get a variant of the BRAHMOS-A ALCM with a range of up to 800 km. "The Sukhoi has a range of 3,600 km. Arming it with an 800 km range missile will increase its reach tremendously, and even more, considering the option of midair refueling," an unnamed Indian official told the daily.

It should be mentioned that the Indian military is now operating land-based and sea-based variants of the BRAHMOS. All brand new and upgraded ships of the Indian Navy are planned to get the missile.

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Re: Indian Missiles News and Discussions - May 2017

Postby sahay » 01 Feb 2018 13:50

prasannasimha wrote:I think there is an error. The first stage was maraging steel. The change to composites has been a steady affair and outdated pieces of information have been jumbled. The first stage of Agni5 is also maraging steel but expect that to be changed too.


You are right. There was an interview of Avinash Chander in Frontline, where he talked about changes made in Agni-III to go to Agni-V.

How did you achieve this quantum jump in range – from Agni-III's 3,000 km to Agni-V's 5,000 km?

We went through various steps. One was that we had to make the upper stages lighter. That was the first and most critical factor. We decided to make both the second and third upper stages of composites. That gave us a major benefit in terms of weight. In Agni-III, both the first and second stages were metallic.

Having made the composite stages, we found that they were coming out better than the metallic stages, strength-wise and property-wise. So we could operate at a higher pressure. So you do not have losses due to gravity, and the losses are reduced. We then went through a total philosophy change. Up to Agni-III, we ignite the upper stage first, then separate the lower stage so that there is no problem of separation.

We decided to leave behind that culture of space vehicles. We now put big retro motors, which create a thrust of four tonnes each – totally 16 tonnes of thrust – just to separate the stages so that no dead weight is passed on to the upper stage.

Correspondingly, we decided to make the mission stronger so that there are no interfaces and the separation is clean. We studied and created extensive models to simulate them on the ground in all types of disturbed conditions in wind tunnels. With all that, we could remove the inter-stages altogether. The weight we had reduced by making the upper stages of composites was fed back into the third upper stage. The weight did not increase overall, but the total energy increased considerably. To reach the 3,000-km range, you need a velocity of five kilometres per second. To reach the 5,000-km range, the velocity has to be more than six kilometres a second.

That was our approach to the repackaging of our vehicle. We made major modifications in the upper stage. V.G. Sekaran, Director, Advanced Systems Laboratory [ASL], DRDO, played a primary role in showing us how to repackage the payload structures so that the weight comes down by 1,000 kg.

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Re: Indian Missiles News and Discussions - May 2017

Postby Singha » 01 Feb 2018 14:12

>> We now put big retro motors, which create a thrust of four tonnes each – totally 16 tonnes of thrust – just to separate the stages so that no dead weight is passed on to the upper stage.

seems like tremendous overkill just to fire up from the top of first stage. these will be eating up weight and propellant that could otherwise make the 1st stage lighter or burn a few seconds longer. what size of rockets do the latest space faring munnas do H2, zenit and falcon use?

16ton is like a JSF engine on afterburner firing up :twisted:

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Re: Indian Missiles News and Discussions - May 2017

Postby JayS » 01 Feb 2018 14:20

Haridas wrote:
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.

What would be a reasonable assumption for cruising altitude of the cruise missile?
Any insight on jet intake design for given cruising altitude and how (for a given engine core) the optimum intake changes depending on design cruising altitude (hope the question itself leads to an insight). I am trying to understand how the 0.25 factor is arrived at.

I used typical cruise altitude, considering it as UCAV, as is claimed. Anyway wording doesn't matter much as the engine still needs to be operated at that Altitude as per specs anyhow. 8km is a pretty typical number and I was just giving a rule of thumb there not specific to any particular engine. May be that was confusing..?

See the table in here: http://www.delhidefencereview.com/2018/ ... lications/

Engine Op altitude upto 8km. Cruise Mach number 0.8. I assumed the "UCAV" would also be designed with operating altitude up to 8km. At 8km, if it has to fly, engine thrust would be almost 1/4 of its rated SL thrust. This is simply from the Thrust variation of a typical jet engine with altitude. Even if we consider 8km/0.8M is not design point, its still an operating condition. A limit condition at that. At that altitude it needs to still produce L (=W) at whatever speed it can (0.8M is reasonable assumption, however, unnecessary for now).

Of coarse it can fly at any altitude lower than 8km with the design which is capable of 8km altitude and would have good margin for additional lift for maneuvering. However due to higher drag, its range will be obviously limited. With given SFC from that table, it would need 1.1*275 = ~300kg fuel per hour if its flying at SL at full thrust or lets say 270kg (keeping some margin on thrust. i.e. cruise thrust < max thrust). In one hour it will travel about 1000km at 0.8M, if it can maintain that speed at SL. Not bad.

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Re: Indian Missiles News and Discussions - May 2017

Postby Indranil » 01 Feb 2018 16:49

Its flight time is 1000 seconds.

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Re: Indian Missiles News and Discussions - May 2017

Postby JayS » 01 Feb 2018 18:15

Indranil wrote:Its flight time is 1000 seconds.


So 1/3.6 of that number. That much less fuel onboard needed.

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 01 Feb 2018 22:22

prasannasimha wrote:I think there is an error. The first stage was maraging steel. The change to composites has been a steady affair and outdated pieces of information have been jumbled. The first stage of Agni5 is also maraging steel but expect that to be changed too.


I think this is best answer and now sahay has provided the evidence to back it up.

I think the wiki article is hogwash.

Case closed.
Thanks sahay I forgot that interview.


So no need for further fratricide....

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 01 Feb 2018 22:45

Rereading the interview posted by sahay, I noticed key design features that Dr Avinash Chander stated.
- Composite casings allowed higher pressure and thus greater thrust. Thrust is proportional to Area*Pressure
The lack of inter-stage and how design changes allowed weight savings.
In other words the first stage section has a composite shell inter-stage as part of the design.
And use of retro rockets improved the separation.
Separation is the most troublesome event in rocket flight.
This cannot be emphasized more.
A5 is a very efficient and highly reliable vehicle.



Having made the composite stages, we found that they were coming out better than the metallic stages, strength-wise and property-wise. So we could operate at a higher pressure. So you do not have losses due to gravity, and the losses are reduced. We then went through a total philosophy change. Up to Agni-III, we ignite the upper stage first, then separate the lower stage so that there is no problem of separation.

We decided to leave behind that culture of space vehicles. We now put big retro motors,
which create a thrust of four tonnes each – totally 16 tonnes of thrust – just to separate the stages so that no dead weight is passed on to the upper stage.

Correspondingly, we decided to make the mission stronger so that there are no interfaces and the separation is clean. We studied and created extensive models to simulate them on the ground in all types of disturbed conditions in wind tunnels. With all that, we could remove the inter-stages altogether. The weight we had reduced by making the upper stages of composites was fed back into the third upper stage. The weight did not increase overall, but the total energy increased considerably.
To reach the 3,000-km range, you need a velocity of five kilometres per second. To reach the 5,000-km range, the velocity has to be more than six kilometres a second.

That was our approach to the repackaging of our vehicle. We made major modifications in the upper stage. V.G. Sekaran, Director, Advanced Systems Laboratory [ASL], DRDO, played a primary role in showing us how to repackage the payload structures so that the weight comes down by 1,000 kg.

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 01 Feb 2018 23:34

^^^^^^16 ton thrust by one poster does not mean retrorocket weighs that much ! The thrust may be high but duration od retrorocket firing is transient and dont weigh that much. The weight could be calculated using the thrust equation and putative near empty weight of the stage. The complexity of retrorocket design etc can be seen. Have a look at
https://www.sciencedirect.com/science/article/pii/S0895717705001482/pdf?md5=04d1c7bc1a0c21dd4886001c81c178ba&pid=1-s2.0-S0895717705001482-main.pdf

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 02 Feb 2018 00:06

4 motors each with 4 tonne thrust. Total 16 tonnes thrust.

Think of the difficulty of lighting all simultaneously.

Its the thrust and not the weight.

And its more like a pulse motor duration less than 0.5 sec to push away the separated first stage from the departing vehicle.


Probably a pancake or idli motor.

Where is the confusion?

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 02 Feb 2018 00:11

Incidentally hot staging has also been used in ISRO rockets over time

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 02 Feb 2018 00:22

The problem of stage separation will not be just about firing synchronously bit also clean separation such that the separating first stage does not tumble or pitch/yaw during separation such that the lip of the separating 1st stage does not hit and damage the nozzle of the second stage motor all the more when it is going in a ballistic trajectory albeit in the boost phase. The timing may have to be regulated based on the calculated separation angle and forces acting at that point and attitude of the rocket as determined by the on-board computer all the more at fairly high speeds.

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 02 Feb 2018 00:26

Liquid based Id's like SS18and Dong feng would require ullage motors (if second stage are liquid )

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 02 Feb 2018 00:33

First thanks for the paper. I like the nice systematic way they developed the solution and determined the degree of error instead of a Monte Carlo analysis.

The space vehicle 'fire in the hole' technique consists of lighting up the departing and giving the separation signal at same time. What this does is push the separated stage with the pressure from the motor exhaust. However if there is a delay in lighting up due to motor inertia (Newton's First law : A moving body continues to move till it comes to rest) could result in bumping which could be fatal.

However in the retro rocket solution the hardware on the departing vehicle has to be thermally insulate to survive the exhaust heat.
But this is a better solution if you can afford the weight of the retro rocket system. Most likely the retros are located in an azimuth does not have sensitive packages in the exhaust path.

----
Just saw comments on tumbling.

The separated stage is like a cylinder and the dome weighs more than the nozzle. So the CG will be forward of the CP and will be stable. However as the remaining fuel is brunt up and since there is no control on it, it could tumble due to atmosphere conditions.

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 02 Feb 2018 07:03

^ that would be true if there was only a linear movement but these engines are still in boost phase but not truly ballistic with minor corrections going on all the time isnt it ? So during the firing of retromotors an ill timed vector could start a pitch or yaw that could make the lip of the first stage booster hit the nozzle and arc ? Also there will be engine cut off timing to factor in too isnt it ? The separation of both staged booster and strap on boosters have been interesting studies in physics.

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Re: Indian Missiles News and Discussions - May 2017

Postby prasannasimha » 02 Feb 2018 07:07

Isnt the first stage separation still in the atmosphere below the Karman line ? (Albeit in thinner atmosphere )

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Re: Indian Missiles News and Discussions - May 2017

Postby Haridas » 02 Feb 2018 11:43

^^^ yes way below Karman line.

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Re: Indian Missiles News and Discussions - May 2017

Postby kurup » 02 Feb 2018 19:34

Two missile tests scheduled from 06 to 08 feb ,

https://twitter.com/kurup89/status/959422444997042177

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Re: Indian Missiles News and Discussions - May 2017

Postby Singha » 02 Feb 2018 21:16

smells like agni1 and prithvi2 . agni1 has not been tested for a long time.

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Re: Indian Missiles News and Discussions - May 2017

Postby JTull » 02 Feb 2018 21:25

On the subject of composite stages, do we know if our ABM missiles have composite stages. They're fairly big missiles and making them composite will allow lower weight, more range, faster time to target, etc.

sudeepj
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Re: Indian Missiles News and Discussions - May 2017

Postby sudeepj » 02 Feb 2018 22:36

JTull wrote:On the subject of composite stages, do we know if our ABM missiles have composite stages. They're fairly big missiles and making them composite will allow lower weight, more range, faster time to target, etc.


They are pretty spindly cylinders.. I would be really surprised if they are not composite given we have built much larger composite motors now.

Its the Brahmos 800kms that is really intriguing. Almost all parts of that missile are aluminum and aluminum alloy. For the 800km range, are we simply changing the structures from aluminum to composite? Or an entirely new missile?

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Re: Indian Missiles News and Discussions - May 2017

Postby nam » 02 Feb 2018 23:11

JTull wrote:On the subject of composite stages, do we know if our ABM missiles have composite stages. They're fairly big missiles and making them composite will allow lower weight, more range, faster time to target, etc.


I could be wrong, but SAM are generally not built of composites. Composites are probably not good at high Gs at specific points, which SAMs are subjected to. Force distributed across the surface is okay.

Moreover the weight savings might not be worth the effort & cost. SAMs are not in 10s of ton class missiles.

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Re: Indian Missiles News and Discussions - May 2017

Postby ramana » 02 Feb 2018 23:31

JTull, Why not look up Wiki for first cut on PDV, AAD etc.?


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