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Indian Missiles and Munitions Discussion - June'14

All threads that are locked or marked for deletion will be moved to this forum. The topics will be cleared from this archive on the 1st and 16th of each month.
srai
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Re: Indian Missiles and Munitions Discussion - June'14

Postby srai » 13 Mar 2017 00:55

Srutayus wrote:
i didnt understand..in the indian subcontinent battle situation/environment will tank formations be engaged at such long distances??

The point of such unrealistic requirements is to keep the indigenous product out and facilitate imports…which by the way will be held to much more realistic standards.


Search for "perfection" continues! Nag was ready as far back as 2010 but no orders have been placed as of 2017.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby ramdas » 13 Mar 2017 08:58

Kanson wrote:Sir, general observation in such scenario is either the missile is faulty if not then there is most likely modifications for which more trials could be needed. My views!


So for the Agni-5, is it the modifications that are causing the extra trials ? If it were faulty, something would come out. Hope it is modified to carry MIRVs soon, and tested quickly. One A-5 test a year is very slow.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Philip » 13 Mar 2017 12:58

Wasn't there an off. report that BMos extended range would be around 600km+? Even if it in the 450-500km range,it is a quantum leap in capability.It means that our warships and subs will be able to stay way out off the enemy's coastline and attack his naval bases,ports and naval assets in port. The max missile range as of now that our mortal enemies possess is around 250-300km. With quick production of the new BMos variant and poss. retro work done on exg. missiles,the IN's strike capability could be quickly further enhanced. It will be also v. interesting to see what if poss. the enhanced range of the air-launched version brings with it!

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Gyan » 13 Mar 2017 14:13

Re Kanson, SSRidhar, Shiv

As per research papers released in 1960s, Ramjet missile has a range 3 times its solid fueled missile weight equivalent. Or lets simplistically say 3 ton Brahmos is equivalent to 9 tons solid fueled missile, something like Agni-1.

We don't know it's glide range especially for an object travelling at Mach 3 at altitude of 14-30km. Terminal speed will be less but will still be pretty high, refer Pinaka. Manoeuvres may decrease but will still be substancial like say AAM which only have single phase boost motors.

I don't have technical answers, but I would be hesitant in accepting range of Brahmos being less than 800-1200km.

nam
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Re: Indian Missiles and Munitions Discussion - June'14

Postby nam » 13 Mar 2017 16:34

So it is 450 KM from sea level.

Of-course unsaid is the range when fired from say.. Batalik at 18000 feet or find a way to do it in Siachien :D

One thing we should always remember is all our missiles will be fired from the beautiful mountains of Cashmere. Left direction for Pakis, on the Right towards Tibet!

This is a prime example where "offical" range is meaningless.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 13 Mar 2017 17:00

Gyan wrote:We don't know it's glide range especially for an object travelling at Mach 3 at altitude of 14-30km. Terminal speed will be less but will still be pretty high, refer Pinaka. Manoeuvres may decrease but will still be substancial like say AAM which only have single phase boost motors.

I don't have technical answers, but I would be hesitant in accepting range of Brahmos being less than 800-1200km.

Some rudimentary calculations, ignoring the most difficult confounding factor here - air resistance can throw some light on this question.

Assume that the Brahmos is travelling at 1000 m/sec (Mach 3 at sea level) but at 30,000 meters (your guesstimate, which I think is too high).

The minute the object loses power it starts falling. Sine there is no air resistance for our calculation let us ignore the gliding part and simply see how long the object will take to hit the ground from 30,000 meters.

The calculation is simple: It will take 78 seconds to hit the earth following a simple ballistic path

Now remember that the missile was travelling a 1 km/sec and is not being slowed by air resistance. That means that it will travel a mere 78 kilometers before hitting the ground, starting at 1000m/sec at 30,000 meters

Now you say that it will glide for a longer distance. That actually complicates things a lot. Gliding is always at the expense of velocity and even streamlined objects that do not glide tend not to reach even Mach 1 speeds and even if they do, it simply causes them to tumble and yaw and turn off course because of Mach buffeting.

But assume that this Brahmos missile glides using high velocity freefall combined with body lift. As it falls its velocity will bleed continuously as the energy is used to provide lift (lift is actually air resistance). It will slow down to speeds less than a streamlined free fall dumb bomb - which would be about 250 m/sec (15 km/minute) losing height as it went. I don't know how long it could glide even at 250 m/sec but 10 minutes of gliding would still take it only 150 km further. In actual fact I think these are gross over estimates, including the idea that the Brahmos cruises at 30,000 meters. For a cylinder like the Brahmos missile even the act of slowing down to transonic speeds will cause plenty of buffeting and instability. I would guess that it would go off course and fall like a stone, tumble and hit the ground within 15-20 km after the power goes off.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Austin » 13 Mar 2017 17:39

^^ Brahmos missile relies on its TVC nozzle of Ramjet engine to provide control and accuracy of its trajectory precisely to centimeter and thats the major reason why it is so darn accurate and can have agile movement at high speed ( has to be as it travels very fast where conventional control surface movement wont be enough ).

IIRC the mid delta wing of Brahmos has flaps but its fixed ( memory fading me but I dont recollect if mid wings are semi- movable )and rear small cropped wings are fixed.

Once the Ramjet engine is cut off , even if they can glide for some distance depending on height , lift generated by body/wings & atmospheric factors , its accuracy will be terrible unless it is falling vertical 90 degrees at the target where only small movement of conventional control surface would be enough for trajectory correction and engine can be cut off , Gliding Long Distance Brahmos wont do any good.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby nam » 13 Mar 2017 18:34

It really does not make sense to have very long range mach 3 cruise vehicle. Instead the planned subsonic cruise + supersonic terminal would be the "long ranged" Brahmos and is the ideal solution.

If I have to kill something at 1000km, I would use a ballistic missile.

Having said that, anyways most of the people we want to target are within artillery range. All that is missing is the will...

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Re: Indian Missiles and Munitions Discussion - June'14

Postby srai » 13 Mar 2017 18:37

One way to achieve 800km within 2-years, as stated by DRDO chief, would be to either increase the size of the first-stage booster or add another stage booster.
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Last edited by srai on 13 Mar 2017 18:43, edited 1 time in total.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Cain Marko » 13 Mar 2017 18:42

Philip wrote:Wasn't there an off. report that BMos extended range would be around 600km+? Even if it in the 450-500km range,it is a quantum leap in capability.It means that our warships and subs will be able to stay way out off the enemy's coastline and attack his naval bases,ports and naval assets in port. The max missile range as of now that our mortal enemies possess is around 250-300km. With quick production of the new BMos variant and poss. retro work done on exg. missiles,the IN's strike capability could be quickly further enhanced. It will be also v. interesting to see what if poss. the enhanced range of the air-launched version brings with it!

About the 600km claim, Wasn't an off report. It was V K Saraswat himself who said it iirc. So lots of fud going on IMHO.

In any case, how will they provide targeting updates for a naval target I wonder when time to impact will be about 10 minutes. A ship could have moved a few 4-5km in this gap. Satellites, ka 31? Or is the bmos smart enough to manage without any such help.
Last edited by Cain Marko on 13 Mar 2017 18:52, edited 1 time in total.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby srai » 13 Mar 2017 18:48

^^^
It's now 800km.

DRDO to extend BrahMos cruise missile range to 450km, thereafter 800km; first test on March 10
February 15, 2017
...
The Defence Research and Development Organisation (DRDO) chief S. Christopher on Wednesday said that DRDO is likely to extend the range of its BrahMos supersonic cruise missile to 450 km from existing 290 km. The first test is to be conducted on March 10 this year. According to Christopher, the missile can be launched from submarines, ships, aircraft or land, with the enhanced range. Christopher also added that BrahMos with a range of 800km will be ready in next two and a half years. The BrahMos, a supersonic cruise missile that carries warheads weighing up to 300 kg and strike targets on land and at sea.
...

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Cain Marko » 13 Mar 2017 18:53

:shock: :D

Do note that chengdu is about 500km from AP as the crow flies. And all of Tibet will be c covered st 800km. pretty much.
Last edited by Cain Marko on 13 Mar 2017 19:00, edited 1 time in total.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby JTull » 13 Mar 2017 18:54

After expending it's fuel, we don't know if the CG of the unpowered Brahmos or it's aerodynamics will allow it to glide and not start tumbling (think of the 300kg warhead upfront and empty fuel tanks at the back).

Also, it will probably need bigger wings to get some lift and fins for minimal corrections of trajectory for accuracy.

Moreover, it will become just a top attack missile, which take away some of the advantages of hitting just above the waterline.

The missile is quite big, so without it's terminal speed it will present a relatively easier target for SAMs.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 13 Mar 2017 19:24

Cain Marko wrote::shock: :D

Do note that chengdu is about 500km from AP as the crow flies. And all of Tibet will be c covered st 800km. pretty much.

The main east west highway can be covered by Tejas. My report is coming up soon.. But that is OT

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Re: Indian Missiles and Munitions Discussion - June'14

Postby ranjan.rao » 13 Mar 2017 20:56

shiv saar given vivek ahuja is on long sabbatical, would be great to have ur report... :D

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Re: Indian Missiles and Munitions Discussion - June'14

Postby vasu raya » 13 Mar 2017 22:51

At 800km range, if Brahmos can cover all of Afghanistan from either the Sea or the Indian border then the talk of 'strategic depth' by our neighbor becomes humbug. That would be a good political cover as well if we don't want to mention Tibet directly yet.

One could sell Brahmos to Afghans and they have the quasi control but the missile battery itself is physically based in India or on the Indian Naval Ships or any ship 'leased to Afghanistan' and protected by IN. To support this, packaging missiles into shipping containers and launching from them may not be such a bad idea. Maybe Afghans could be recruited into MTCR.

It won't be more of a farce than Pak launching painted Chinese missiles say from Chinese built subs, whose control is never clear but Pak will claim absolute ownership anyways.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Bheeshma » 13 Mar 2017 23:02

Lets start with giving Prithvi'-I and II to ANA. A 350 Km range itself will deflate the pakis completely.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Gyan » 13 Mar 2017 23:35

Re Shiv, if Brahmos is aimed upwards at 30km it will not stop climbing till it's speed becomes zero like a Shell. You may be confusing the calculations with one for a bullet fired in a flat trajectory. After reaching pinnacle, say 60km, it will start falling in an accelerating mode towards ground, and more it accelerates, the more maneuverability, glide range it will gain, just like any AAM fired in lofted mode. The altitude glide ratio from the height of 30-60km can be anything from 5 to 10:1, which can add a few hundred km to range. Sea dart Ramjet missile had range of 40kt powered then another 20kt glide range to hit an aware maneuvering air target.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Kanson » 14 Mar 2017 03:44

ramdas wrote:
Kanson wrote:Sir, general observation in such scenario is either the missile is faulty if not then there is most likely modifications for which more trials could be needed. My views!


So for the Agni-5, is it the modifications that are causing the extra trials ? If it were faulty, something would come out. Hope it is modified to carry MIRVs soon, and tested quickly. One A-5 test a year is very slow.

A5 development started at that time where tensions on N & NE borders were running high. Compared to their std 5 yr, this was completed in 3 years time. Major sub systems were tested in other missiles prior to its maiden test flight. It was done with such alacrity. Initial test and the subsequent ones were declared as success - no failures.

In such circumstances where initialy it was rushed through followed with more trials than std, it gives the impression either missile design is faulty, concocted in urgency so needs more trials for correction,
Or..if not faulty then missile is undergoing further enhancements or modifications.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Kanson » 14 Mar 2017 04:10

Gyan
Reg Pianaka: even say it attain high terminal velocity, every turn and bank consumes energy so reduces speed. So to maintain speed while doing such loops and manoeuvres it needs to be powered.

Reg AAM: to fly like AAM the body needs to generate lift. Take Astra, check the size of wings, chech the thin dia that holds these large wings. Compare & contrast with Bhmos's dia/body, does it have such large wings?
And it need wings big enough or it should produce sufficient energy to lift 2.5 ton missile. Does it have such wings?

Third, yes you can flip the nose up and project like ballisitic missile. Pls note height ceiling is only 14 km beyond that engine shuts down. So project it like RV with weight of 2.5 tonnes, burn out velocity of Mach 3 at the alt of 14 km. Now see for yourself with such spec how long it goes and what range it covers.
Last edited by Kanson on 14 Mar 2017 04:11, edited 1 time in total.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby PratikDas » 14 Mar 2017 04:11

Kanson wrote:
ramdas wrote:
So for the Agni-5, is it the modifications that are causing the extra trials ? If it were faulty, something would come out. Hope it is modified to carry MIRVs soon, and tested quickly. One A-5 test a year is very slow.

A5 development started at that time where tensions on N & NE borders were running high. Compared to their std 5 yr, this was completed in 3 years time. Major sub systems were tested in other missiles prior to its maiden test flight. It was done with such alacrity. Initial test and the subsequent ones were declared as success - no failures.

In such circumstances where initialy it was rushed through followed with more trials than std, it gives the impression either missile design is faulty, concocted in urgency so needs more trials for correction,
Or..if not faulty then missile is undergoing further enhancements or modifications.

Agni 5 flew a long way - a flight path that would've easily been monitored by the MTCR members at the time. If Agni-5 flights were rubber-stamped as being successful, I can't imagine us subsequently getting into MTCR. Instead, the cacophony of humiliation from international media would've been evident. I think we got into MTCR because the A5 flights were successful and because those with experience could work out the true potential of the platform (range, MIRV, etc.)

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Kanson » 14 Mar 2017 04:24

Ah! Want to believe that(MTCR part) and whatever is happening i believe it is good. Rather than having another missile named as A5prime down the line after 5 yrs....it is good.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby ramdas » 14 Mar 2017 06:09

@Kanson: Indeed looks like A5 is slowly undergoing modifications for improved performance. OTOH the threats that precipitated the initial rapid development have not reduced. They have worsened. Still, GoI appears to be moving slowly w.r.t. A5. A4 OTOH has been deployed with alacrity. Hope GoI does not end up relying on a dissuasive A4 force +unkil alliance. Initial A5 variants must be deployed as well, with upgrades continuing with each production batch.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 14 Mar 2017 07:09

Gyan wrote:Re Shiv, if Brahmos is aimed upwards at 30km it will not stop climbing till it's speed becomes zero like a Shell. You may be confusing the calculations with one for a bullet fired in a flat trajectory. After reaching pinnacle, say 60km, it will start falling in an accelerating mode towards ground, and more it accelerates, the more maneuverability, glide range it will gain, just like any AAM fired in lofted mode. The altitude glide ratio from the height of 30-60km can be anything from 5 to 10:1, which can add a few hundred km to range. Sea dart Ramjet missile had range of 40kt powered then another 20kt glide range to hit an aware maneuvering air target.

:rotfl: Fertile imagination and goalpost shifting but you cannot change physical laws.

You first state that the Brahmos will glide down from 14-30 km. Now you are saying it will climb to 30 km and coast higher - you are using the figure 60 km. There are huge holes in this fascinating idea even if one ignores the goalpost shifting of altitude from 14 km to 30 km to 60 km

1. There is virtually no atmosphere for gliding above 30 km
2. Gliders need wings AND air. The HTT 40 has a glide ratio of 11:1. The MiG 21 - 8:1, The Space shuttle has a glide ratio of 5:1. The Brahmos glide ratio with its stub wings is probably 2:1

It will fall like a rock

PS by kt did you mean km? "kt" is "knots" - nautical miles per hour - an indicator of speed. Kt is Kiloton = explosive yield in thousands of tons of TNT

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Re: Indian Missiles and Munitions Discussion - June'14

Postby LokeshC » 14 Mar 2017 10:08

Shiv saar. Glide is also a function of velocity. High mach objects can and do glide well above 50 km.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Austin » 14 Mar 2017 10:49

BRAHMOS ISLAND STRIKE TEST IN 2015


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Re: Indian Missiles and Munitions Discussion - June'14

Postby Singha » 14 Mar 2017 11:05

LokeshC wrote:Shiv saar. Glide is also a function of velocity. High mach objects can and do glide well above 50 km.


I would imagine thats also how BGRV works...the "glide" part of boost-glide.

https://www.slideshare.net/ramana_56/bg ... -c-9600008

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Re: Indian Missiles and Munitions Discussion - June'14

Postby LokeshC » 14 Mar 2017 11:08

Yep. I had a Nasa (1950s) doc on what can be done with upper atmospheric glide vehicles with all the equations of drag etc that someone with very basic understanding of drag equation etc can understand. I am trying to search for that one. I will post it if I find it.

Infact some meteors skim the atmosphere at 100+km height because they are coming in so fast that even the super thin atmosphere provides them with the lift (at the cost of some velocity) to bump them higher. So if they are angled right, they will bobble up and down just like a rock thrown into a pond at a very special angle that make it skim over the surface before finally entering the water.

At extremely high velocity the ultra low density air becomes as thick as concrete. And depending on your Beta and Drag, you either burn up or glide and escape.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby prasannasimha » 14 Mar 2017 14:36

There is (or rather was )even a reentry corridor Goethe space shuttle. Two low an angle and you would flip and bounce out (even at that rarefied atmosphere) and two high an angle and you would be unable to control the descent and burn.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 14 Mar 2017 14:47

LokeshC wrote:Shiv saar. Glide is also a function of velocity. High mach objects can and do glide well above 50 km.

On BRF this post would be classified as "general knowledge"

A lot more detail is needed other than the statement that gliding using body lift at high speed is possible

The initial premise was that Brahmos will travel its full distance of 300 km at 15km (or even 30 km) altitude reaching Mach 3 and then glide without power for 300 km further using body lift and high speed. I posted several objections to this premise but the reply was a change of goalpost that was even less likely. This time it was postulated that Brahmos would be launched straight up to reach an altitude of 30 km (or even 60 km) and then it would turn and travel (glide at high speed) for 600 or 800 km. I do not believe this is possible

I was unable to find any data to support this idea either in posts made on this thread (including yours) or on searching the internet.

An object coasting at Mach 3 at 60 km without power cannot glide because of lack of enough atmosphere at 60,000 meters

Useful gliding starts at 30 km (30,000 meters/100,000 feet)

No bomb or artillery shell falling from the sky without power - either as free fall or glide has been recorded to have a terminal velocity of more than Mach 1. 250-330 meters per sec are all quoted in various sources.

No unpowered object (such as a Brahmos without engine power) coasting at 3 mach will come down to earth and still remain at Mach 3 or go faster. That is physically impossible. It will slow down. Even streamlined free fall objects (such as bombs) slow down and objects that glide will bleed energy for lift.

So I am certain that a Brahmos travelling without power at 30,000 meters at Mach 3 is NOT going to glide 300 km or even more than that. I suspect it will simply fall out of the sky in 15-20 km, but the latter is my guesstimate.

I would be happy for someone to provide hard data rather than vague generalizations like "this can happen" or "that can happen".

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Gyan » 14 Mar 2017 15:03

Re Shiv, SSridhar, Kanson

I have been claiming that Brahmos 1000km missile for a long time primarily on the basis that (as per scientific papers published in USA in 1960s) range of Ramjet is 3 times the equivalent solid fueled missiles. So we have to see Brahmos as a 9 ton Single Stage Solid fueled missile. Even ATACMS with a weight of 1700kg and 250kg warhead has 300+km range. There was no way the range was only 290km for Brahmos.
Now we know that Yakhont = Russian Brahmos has a range of 450km in hi-hi-lo mode, so it should be reasonable to claim the minimum “powered” range of 600km for hi-hi-hi mode.

Now if look at articles for Ramjet missiles especially from USA in 1960s, a max height of 100,000 feet and throttable speed upto Mach4+ was claimed. (Look at SR-71, Mig-25 also)

The issue is whether the Ramjet missiles starts tumbling after the fuel is over or it is still controllable. Then the data is available for Sea dart (which is also a cylindrical missile with small fins) which shows that Ramjet missile also has additional range due to coasting, gliding etc for additional 20 knots ( around 38km) for a SAM which needs to retain more maneuverability compared to ground attack missile.

Now further we have seen that Ramjet missiles were used in 1960s as SAMs even with small fins. So we have to ask ourselves whether Brahmos can be used against enemy awacs at range of 500-700km? If Indian Awacs detect an enemy Awacs (800km) away, can it call upon a Brahmos battery? Even a “possibility” of such a course of action places tough choices upon the enemy.

Now coming to maximizing ground attack range. The issue is whether the missile has to be “powered” til it hits the target or it has coasting, gliding range even with small fins? Now I am assuming that for a static target on ground, the missile can hit it after a coasting phase and it can be controlled & will not tumble. In my theoretical scenario, If the fuel is expended at max height of 30km but the missile is oriented towards upward climb say 20-30 degrees, then due to minimal friction, how long & how high will it climb with initial speed of Mach 2.4-Mach 2.8 ?? It requires tough and complicated calculations (beyond my school boy ability) but lets take another 30km and 100km range? Thereafter it will coast back to ground all the while gathering speed & maneuvering ability? (Even Indian 1000kg bomb with only tail end fins is supposed to have a range of 30km if released from 12km at Mach 1.2) So what will be the speed, distance and terminal angle of attack? Mach 1.5, another 100km, 30-60 degrees ??

Note :- Gliding would be function of air resistance acting against the flight and also assisting the fins. Alongwith this, we have to consider the basic semi parabolic/ballistic path initially due to velocity to climb up and then due to gravity to fall down. It will neither climb straight up nor fall straight down.

Basic Calculator

http://keisan.casio.com/exec/system/1225100367

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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 14 Mar 2017 15:50

Gyan wrote: In my theoretical scenario, If the fuel is expended at max height of 30km but the missile is oriented towards upward climb say 20-30 degrees, then due to minimal friction, how long & how high will it climb with initial speed of Mach 2.4-Mach 2.8 ?? It requires tough and complicated calculations (beyond my school boy ability) but lets take another 30km and 100km range?

Your linked calculator says 42 km max height and 125 km - in the absence of air resistance


Gyan wrote: Thereafter it will coast back to ground all the while gathering speed ...

This is the problem part.

How can an unpowered glider gather speed? A glider that gathers speed will generate lift. That lift will raise its altitude and lower its speed. Eventually because energy is lost due to friction there is a net loss of energy and therefore speed and altitude. It will hit the ground much slower than it was flying when it started.

Even a streamlined object like DRDO bomb mentioned by you in free fall, will generate a small amount of "body lift" as it accelerates and this will again follow what I said above. The lift will slow its descent but use up some energy and slow its speed as well. Free fall bombs have been measured hitting the ground at 250 m/sec (less than Mach 1)

There is no guarantee that it will hit anything at more than Mach 1. The slower it is the more likely it is to go into freefall mode. Whether it falls nose down or not depends on whether it was designed for gliding or not. Like any glider it could stall and tumble/spin

  • HTT 40 with huge wing area to weight ratio has 11:1 glide ratio
  • MiG 21 with smaller wing area to weight ratio has glide ratio of 8.5:1
  • Space shuttle with recognizable wings and large underfuselage lift surface had 5:1 glide ratio
  • Brahmos with small stubs for wings and mainly body lift at high speed is unlikely to maintain even a 5:1 glide ratio. My guess is maybe 2:1 overall as it descends and slows from Mach 3 down to maybe Mach 1

A Brahmos at 45km altitude is unlikely to reach 100 km in an unpowered glide especially because its ability to glide will all but vanish as its speed decreases.

A Prithvi/Agni 1 would be better than Brahmos instead of all this convoluted stuff.

shiv
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Re: Indian Missiles and Munitions Discussion - June'14

Postby shiv » 14 Mar 2017 15:57

Incidentally a different calculator posted on the link provided by Gyan says how long and object would take to fall from 45 m and what terminal velocity it would reach.
http://keisan.casio.com/exec/system/1224830797

I am using a 2000 kg mass of Brahmos without fuel. It will take 3 minutes to free fall from 45 km and reach a maximum velocity of just 285 m/sec

If there was no air resistance it would reach a velocity of 939 m/sec and fall in just 96 sec
http://keisan.casio.com/exec/system/1224852055

That is the difference that air resistance makes

Austin
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Re: Indian Missiles and Munitions Discussion - June'14

Postby Austin » 14 Mar 2017 15:59

1 problem I can think of is Brahmos with the current engine is limited to max 15 km altitude ( min DRDO has mentioned is 5 meter ) , I think their ramjet wont be burning efficiently well above that altitude and if it did they would have made brahmos fly at 30 km and got much higher range and much greater lookup capability for its radar.

The best in theory presentation I have seen on Brahmos from DRDO was at last AI where they mentioned of "modified" brahmos flying at 17 km and getting a range of 600 km ......Now the word modified can been many thing here including longer length , more effecient ramjet design to burn at higher altitude , larger fuel capacity etc

From recent Dr Christopher statement it seems they have given up on that and rather build something new to get a longer range of 800-850 km
Last edited by Austin on 14 Mar 2017 16:01, edited 1 time in total.

Singha
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Re: Indian Missiles and Munitions Discussion - June'14

Postby Singha » 14 Mar 2017 16:00

I had advocated that shourya be also modded into a anti airspace denial weapon of 1000+km range against large non manouvering targets in the enemy rear like tankers, awacs to play havoc by using OTH radars and airborne awacs to get target info. it could release a KV of sorts based on a cluster of 4 bundle astras each of which will independently go active for the terminal 40km phase. :twisted:

it anyways has a depressed flat hypersonic flight trajectory...ideal to hide under radar horizon longer.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby Austin » 14 Mar 2017 17:19

Delhi Defence Review‏ @delhidefence
https://twitter.com/SJha1618/status/841559410652655617


Here's footage of the Brahmos Block III steep dive mountain attack variant being tested from Car Nicobar.



Austin
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Re: Indian Missiles and Munitions Discussion - June'14

Postby Austin » 14 Mar 2017 17:23

IF that steep dive capability hits any flat top at 90 degree , that will cause far more destruction to any flattop then hitting it on the side.

A big hole in the middle of flattop at the least would mean your aircraft cant take off or land

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Re: Indian Missiles and Munitions Discussion - June'14

Postby SSridhar » 14 Mar 2017 17:48

Austin wrote:Delhi Defence Review‏ @delhidefence
https://twitter.com/SJha1618/status/841559410652655617


Here's footage of the Brahmos Block III steep dive mountain attack variant being tested from Car Nicobar.

This must be the May 8 & 9, 2015 tests at off Car Nicobar to test the new near-vertical capability (65-70 deg) of Block-III missiles.

BrahMos Chief Sudhir Mishra said, after the above tests, “The land-attack missile was tested in the eastern sector for a distance over 200-km on Friday(8th May 2015) and Saturday. The tests have once again established the missile as an incredibly lethal weapon with pinpoint accuracy to take on enemy targets anywhere. On Saturday, the fire-and-forget missile literally hit the same spot it had hit on Friday, proving repeatability. This was the 48th test-firing of BrahMos,”

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Re: Indian Missiles and Munitions Discussion - June'14

Postby LokeshC » 14 Mar 2017 22:17

shiv wrote:
LokeshC wrote:Shiv saar. Glide is also a function of velocity. High mach objects can and do glide well above 50 km.

On BRF this post would be classified as "general knowledge"

An object coasting at Mach 3 at 60 km without power cannot glide because of lack of enough atmosphere at 60,000 meters


:mrgreen:

I missed that detail. Ok Mach 3 at 60km is a stone that's falling straight down.

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Re: Indian Missiles and Munitions Discussion - June'14

Postby ranjan.rao » 15 Mar 2017 00:32

Austin wrote:Delhi Defence Review‏ @delhidefence
https://twitter.com/SJha1618/status/841559410652655617


Here's footage of the Brahmos Block III steep dive mountain attack variant being tested from Car Nicobar.



There seems to be two separate impacts, the first one is small without any fireball and second is a big one with a fireball


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