Klub ASCM and Kilo Upgrades

Rudra
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Re: Klub ASCM and Kilo Upgrades

Post by Rudra »

India has just a few naval bases, does not undertake
particularly long deployments or long range (say near
kola peninsula)...so logistics problems will not
be so severe.

in most Indo-Pak fights I would think ship goes
out, fights for 10 days, expends its load, comes
back once to reload, goes out once more...by which
time PN is gone...and the job is more commerce
raiding and policing, plus stray ASW work if subs
are still surviving.
geeth
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Re: Klub ASCM and Kilo Upgrades

Post by geeth »

>>>Geeth, by tracking the outgoing shells, you know not only if you are missing your target but also by how much. It works just like tracers do for a machine gunner on a dark night.

Badar,

In the case of tracers, it is only one or two shells. But here you have much more of them. The basic argument that I am trying to put in is the complexity of the problem due to a large number of variables - EACH shell coming out of EACH barrel will have different trajectory and the roll, pitch, temperature of the barrel, wind force all affects performance - and hence the accuracy sought by employing a closed-loop system may not be achievable.

=============

IMO the most important difference between Yakhont and Brahmos is the engine - Brahmos is fitted with a liquid Ramjet engine which has a higher specific impuse - a first in the world.
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Re: Klub ASCM and Kilo Upgrades

Post by Badar »

Hi,

EACH shell coming out of EACH barrel will have different trajectory and the roll, pitch, temperature of the barrel, wind force all affects performance - and hence the accuracy sought by employing a closed-loop system may not be achievable

geeth, we are not looking for sub-millimetric accuracy here - most AShM, evem headon, have a fairly large aspect (for the purposes considered here). And a slight scatter of a milliradian or two might not be undesirable (takes care of targetting inaccuracies). The fact that current CIWS (even close looped ones) are not perfect is evident from the high rpm of their guns.

Manufacturers of Phalanx and Goalkeeper say they have the problem beat for practical applications. Most operators are satisfied that the performance is better than that of ordinary radar directed artillery. I dont see any pressing reason to believe that any closed loop gatling gun system is too complex to be operationally viable.
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Re: Klub ASCM and Kilo Upgrades

Post by Austin »

Has it ever crossed your thoughts that the Akash and Trishul may be superior or different compared to what is available elsewhere?
And that the technologies in the Akash and Trishul SAM's arent necessarily the same as in Brahmos..a CRUISE MISSILE?
Indian experience in INS and seeker technology isnt miniscule as you seem to suggest.
And you fail to consider that India wishes to have a substantial stake for the sake of building upon its technological base.
>>>>>>>Thats an interesting point Nitin , sometimes it really make me think wheather the delay is due to the inability to master certain technology weather the armed forces requirement has changed so as to make necessary changes in the the technology of Akash & Trishul , Its really hard to believe that these missile which were supposed to get inducted by 1998 or so is getting delayed by 5-6 years ie 2003-2004 , is it possible that limited production has been started and we are working on Mark-2 variant , I have with me this old indiatoday 1989 , in which the original range of Trishul was mentioned as 6 km and now as we know it is mentioned as 9 Km even there is this media speculation of 50 Km and so on whats the Truth , I wouldnt be suprised if any of our SAMS comes out with much better specification than what is known in the Public .

>>>>> Bhramos IMHO is as win-win suitatiom for both India-Russia for India this is perahps the quickest route to gain knowhow and master the tech for a Supersonic AShM and for Russia they could also gain knowledge of Guidance Technology and other knowhow gained by India , and ecnomically too they will be benifited , Not to mention if sucesssful in exporting it , then financial benifit will be immense .So Nobody is a losser here
Go back and read i was replying to austin's post the brahmos will use israeli seeker. I suggested that DRDO will may seek israeli assitance. But currently israel is not part of Brahmos project because russia doesn't exactly trust israel.
John ,This is the idea I got Which going through various forums discussing this subject , But if there is a problem as such with Guidance etc there is no harm in taking help from Israel if it could help us speed up development . we had similar Jointventure with MKI and Mig-21 upograde , never know one day we could be exporting Bhramos to the Israel :-)

India ad Russia is also working on 18-20 Major Projects , as publically knon these are Bhramos, MTA , 5-gen fighter, Anti-missile defence
does any one have any idea as to what these remaining major projects could be
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Re: Klub ASCM and Kilo Upgrades

Post by Austin »

[bold] TRISHUL vs BARAK [/bold]

There is an interesting debate on CIWS , But I would also like to draw member attention to our own trishul and compare it with barak system.
Although Trishul had some problems mostly due to it Guidance , But recently it also went some sucessfull test , and by 2003 it is supposed to be industed in the armed forces although Trishul is a triservice missile , But it is the Naval version that has been drawing attention in the media as well as the Forum.
Comparing the characteristics of the two system I find that the Trishul system has a unique advantage as compared to Barak syatem.

>>>> Barak has its own unique advantage like , high fire power ,supersonic ( Mach 1), greater kill radius , advanced guidance , modular system , and most importantly it has been tested against AShM like Harpoon( The American had also evaluated the barak and were very impressed by its qualities).

>>>> Trishul also boasts of High Fire Power ( though it lacks VLS capability , But no reason to believe that it cant be overcome and perhaps DRDO might be working towards it) , Advanced Guidance ( Operates in the Unjamable K/Ka band has the capability through BURN through most of the Known Counter measures, also cannot be detected by most of the RWR ) ,Also an IR/EO guidance is being built for the Trishul system Exteremly Monuverable, and most importantly is the sheer speed of the Missile more than Mach 44.5 , which makes it also very capable of intercepting a Supersonic Missille , which the Barak is not capable of doing.
If a VLS capability is developed and the Range is doubled to 20 -22 km trishul has the capability of being be one of the Most lethal Anti - AAShm , Comparable to Aster-15 again IMHO .
Probally Due to it features The Navy has decided to wait for Trishul for its Bhramaputra class frigate , and IMHO the missile is worth waiting for.
Comments & Suggestion from Members are welcome
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Re: Klub ASCM and Kilo Upgrades

Post by Guest »

Exteremly Monuverable, and most importantly is the sheer speed of the Missile more than Mach 44.5 , which makes it also very capable of intercepting a Supersonic Missille , which the Barak is not capable of doing
Shouldn't it be mach 4.5??
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Re: Klub ASCM and Kilo Upgrades

Post by Nandai »

Austin, you forgot the biggest advantage Barak has over Trishul, it is in service, and has been ordered by several countries.
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Re: Klub ASCM and Kilo Upgrades

Post by Austin »

Shouldn't it be mach 4.5??

Sorry Rahul Typo error

Thats True Nandai Barak is an operational system , But it does not take away the qualaties of Trishul.Trishul has been extensively tested and still being tested , I personall feel that once it enters the service , all doubts about Trishul will be thing of the past
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Re: Klub ASCM and Kilo Upgrades

Post by Guest »

Austin,
Any thoughts on when the Trishul will be inducted in the navy?
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Re: Klub ASCM and Kilo Upgrades

Post by John »

Barak in israel service is actually used as short range missile system but IN will recieve CIWS version of it. However very little information is available on which IN vessels Barak has been fitted on and its specs. All i know is IN paid 200 million for 7 Barak systems, each system is comprised of 2 8 cell launchers. I guess price tag of 30 million per system which may be the reason why it is not being fitted into Brahmaputra Frigates.
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Re: Klub ASCM and Kilo Upgrades

Post by Austin »

Rahul , the Naval version of trishul is suppose to get inducted by 2003 , Atleast one can expect Limited production & Delivery , Bharamaputra class frigate will be the First Naval ships to get these missile , Although one cannot be absolutly sure about it , If Trishul gets delayed any further then perhaps we could VLS system with modular construction , as the Twin Arm version carrying 4 missile dosent look suitable for induction in any other vessel in the IN
Barak in israel service is actually used as short range missile system but IN will recieve CIWS version of it. However very little information is available on which IN vessels Barak has been fitted on and its specs. All i know is IN paid 200 million for 7 Barak systems, each system is comprised of 2 8 cell launchers. I guess price tag of 30 million per system which may be the reason why it is not being fitted into Brahmaputra Frigates.
Barak is used by Israel Navy & as well as the Singapore Navy , to the best of my Knowledge , all of them use it for short range Anti-missile role although one might call it as CIWS , when i visited Virat a few months back , I learnt that Virat was suppose to have 2 Systems and the remaining going on Delhi & kashin class destroyer after mid life refits of the later, But as of now that plan still holds is not confirmed , But I should say that the Chief Gunnery Officer who was incharge of Barak system on Virat , when asked as to which was the best wepon system on Board he Promptly replied it was Barak and he was very much impressed by its performance.
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Re: Klub ASCM and Kilo Upgrades

Post by Nandai »

The chilean navy also uses Barak onboard its heavily modified County class destoyers.

http://www.hazegray.org/worldnav/americas/chile.htm

Venezuela has the ground launched version of Barak on order, the system consists mainly of the Barak launcher and a Flycatcher radar.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

In a recent interview to TOI Prof Yash Pal says between a proven system like Barak and an unproven system like Trishul , it is better to chose the proven type.Also he says is the brand hype.He advises India to aggressively market ist own brands.He aslo adds our misslie programs Trishul and Akash are on track but the LCA and MBT have had slippages.
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Re: Klub ASCM and Kilo Upgrades

Post by Raj Malhotra »

I think we are ignoring an important aspect that anti-missile systems have reaction times. A anti missile missile can have warm up time of anything upto 5-25 seconds. Also the missile needs time to gain speed to gain maneuvering capacity.

Also it is very difficult for even an already on radar to track and “lock on” to a fast projectile in mach 2.5 range. Apart from the time taken to power up, track and lock on the target. An incoming missile has a very very small radar cross section and is also shielded by the sea/ground clutter.

US can attempt/can shoot down Mach + missiles due to its sophisticated radar system.

Pakistan will never know what hit it.

Further multiple missiles can be fired to overwhelm the CWIS system.

Fast maneuvering and chaff system can perhaps decoy the missile if the ship knows there “is” an incoming missile.

Even chaff needs to open and spread which takes time. Also missiles can fly through the chaff and re-acquire the ship.

If multiple missiles fired from different directions approach the ship then the ship must put chaff between itself and all the missiles and then mask its own presence.

Also to track the missile the ship needs to keep its radar on and which makes it a candidate of ARM.

Also command guidance after gathering info through UAVs, aircraft, manned sonars and radars can be provided to missiles.

With lack of good medium range missiles Pakistan ships will also be candidate for LGBs.

Not to forget that Popeye turbo is supposed to IR guided also.

The point is Indian navy simply too powerful. Compared to Pakistan navy.

I donot think any surface asset of Pakistan navy will survive 48 hours.

Among subs only agosta is at threat. Rest are too old.

Once agosta fires its first missile it will become the target for the whole IN as by this time Pakistan surface navy would have ended.

Klub is the present and Brahmos is the future. with these two missiles India will remain contemporary in forseeable future say next 20 years.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

I just wanted to know has the ground forces version of Trishul been inducted ? Sorry for asking this question.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

Also can anyone say what is meant by "guidance does not work ?" Isn't it too general ? What aspect of guidance does not work ?
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Re: Klub ASCM and Kilo Upgrades

Post by shiv »

Originally posted by Badar:
Hi,

Geeth, most CIWS are autonomous - there is no gunner
etc etc
BTW, CIWS wont fire hundreds of shell at a single target. While the rpm is very high (the best of class being around 10,000 rpm), the guns are fired in very short bursts. Most CIWS dont cary more than a few hunderd ready rounds in all.
Two comments from a person who does not know a lot about this.

These guns are fired from a ship - so that there is ALWAYS some movement of the gun relative to target. No human would have a hope in hell of correcting for pitch, roll and other random movement while trying to hit a 30 cm wide target approaching at 150 metres per second or more with 10 seconds before it hits. An unemotional closed loop system seems logical if only for that reason.

Besides - any gunner would fire off his available 1000 rounds in 0.1 seconds if he was given the controls. Brrp. That's it.

Having said that:
What does CIWS stand for?
What is AHEAD?
What is 3P?
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

I have always wondered why a SHORAD like Trishul was done as a radar guided missile.For such short ranges , IR guidance is the best and in fact the safest.

We could have just taken the Igla projectile and extented its range to 10 km and fitted it with an IR seeker either made by us or the Israelis , done the data processing ourselves , including methods for avoiding flares , discriminating against false targets etc.It would have emerged as the deadleist IR SAM in the world , given our strengths in software.

8 of these could ahev been mounted on a BMP and it would have taken out any target at clsoe ranges.Including PGMs.

If we are willing to add command guidance by LOS we could have added another 10 km to its range.A primary IR sensor tracks the targets when its 20 km away , launches the missile and guides i by radio commands until it is close enough to acquire teh target by its own sensor.It would have had 100 % kill probability.

It would have also been an effective AAShM.Better than even the supersonic Barak II.A Radar Guided AAShM always has the chance of losing its quarry as RCS becomes smaller and smaller and esp if its skims low over the surface.But an IR missile would easily pick up an AShM against the blackness of the water , as water always absorbs IR radiation.The Trishul Projectile with an IR sensor trvaellling at Mach 4.5 would knock off almost all known AShM including perhaps the BrahMos.If it were fitted with Bionocular IR sensors , Kill probability is enchanced even more.

On the other hand the ground based Trishul in its current configuration is most vulnerable to destruction in the battlefield.If it satyed on to acquire a target before it enters the envelope of teh missile , it runs the risk of being HARMed or being taken out by PGMs.If turns on at the last minute , and even with the low 6 second reaction time, the aircraft would ahve gotten clsoe enough to shell the radar antenna and the vehicle with canon fire and rockets , no need for even ARMs.

Perhaps the missile makers were aware of this fact which is why they ahve put a terminal IR seeker in the missile.
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Re: Klub ASCM and Kilo Upgrades

Post by Roop »

Originally posted by Shiv:
...there is ALWAYS some movement of the gun relative to target. No human would have a hope in hell of correcting for pitch, roll and other random movement while trying to hit a 30 cm wide target approaching at 150 metres per second or more with 10 seconds before it hits. An unemotional closed loop system seems logical if only for that reason.
The compensation for ship's movement (roll/pitch/yaw) is done by the gyro-stabilization system of the gun mount. The CIWS is a stabilized platform. This has nothing to do with whether it is an open-loop or a closed-loop system.

This has already been explained by Badar, but to continue: If the system has the electronics and the "smarts" to track and follow (simultaneously) its own shells as well as the incoming missile, it is a closed-loop system. The makers of the Phalanx claim that it can do this. One may have one's own doubts about whether the claim is accurate, but if it is, the Phalanx is a closed-loop system. Competing CIWS systems (the Russian one, for instance) may lack the ability to simultaneously track outgoing shells and incoming targets, therefore they are open-loop systems. This does not prevent them from being stabilized platforms.

No navy (or at least, no navy with reasonably intelligent people in charge) would attempt to deploy ships that relied on non-stabilized platforms for their weapons and weapon-control sensors (FCRs etc.).
What does CIWS stand for?
Close-In Weapon System
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Re: Klub ASCM and Kilo Upgrades

Post by Nandai »

Originally posted by shiv:
What is AHEAD?
What is 3P?
Well, AHEAD is a special sort of ammunition developed by Oerlikon, each shell contains, if my memory serves me right, 152 tungsten subprojectiles. These subprojectiles are released from the shell in a coneshaped pattern at a certain distance from the incoming target. They might not be able to destroy the incoming missile, but they will destroy the control surfaces, seeker and other important parts of the missile, causing it to miss the ship, or even destroy itself due to the damage caused.

3P is a very similar by ammunition, but it is developed by Bofors. 3P stands for prefragmented, programmable, proximity-fuzed ammunition.

http://www.boforsdefence.com/eng/products/nav3_3p.htm

For more info about 3P, check out this video at Jane's.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

I think one possible way is to develop a 155 mm shell with IR seeker and deployable fins to attack an AShM.High muzzle velocity will ensure good interception possibity.
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

--------------------------------------------------
I think one possible way is to develop a 155 mm shell with IR seeker and deployable fins to attack an AShM.High muzzle velocity will ensure good interception possibity.
--------------------------------------------------

An 155mm shell whould have to be fired from a very long barrel. Add to the distance of the ship and the incomming missile , even an 0.1 degree pitch/roll/yawn can result in missing the intended target, possibly by a large margin.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

I think there is unwanted confusion over the closed loop system here.The closed loop system is where there is feed-back control mechanism.

That is , suppose you wish to orbit a satellite.There are two ways of doing it.One you calculate the required trajectory and give commands to the rocket to turn aroudn at specific points.Like after 10 seconds turn by 5 degs to North etc etc. This way you make teh rocket to travel in particualr trajectory and ensure it makes to orbit.But you dont make any provision to check whether it has indeed turned by 5 degs in teh required direction.There is a posiblility due to wind or some partial failure of equipment liek nozzle it turns only 4 degs.But you never check by Radar to verify that.The net result is there is some error and ist of its original trajectory.After 15 secs when you ask it to turn 3 degs South , and it does only 2 degs , both the errrors add up , and in this way teh satellite dosent reach intended orbit precisely.

In closed loop after every instruction you check whether what you want has been done , and if ist not done , give another command , say aask it to turn another 1 deg N in the first instance and 1 deg S in the second instance to correct the trajectory.

In other words its like this :

instruction ---> action ------> verify action -----> instruction.

OR :

sense object ----> give correction -----> sense object ----> give correction.

So its like a loop repeating itself , hence the term.

In case of teh CIWS it keeps track of teh AShM and keeps changing elevation of gun to change in missile position and keeps firing until it detects a plume of explosion when it stops giving commands to fire at teh target.Its a closed loops ystem only.

If it were open loop it would simply keep firing at the assumed position of the AShM even after the target is destroyed.It makes no effort to
check the out come of its firing instruction.

The Russian system is a closed-loop system.

The Phalanx capability to track out-going shells is just an added feature.

The basic aim of CIWS which rely on gatling guns is less on accuracy but more on brute force.The GG would ahev been tested on land and the deviations well know.When the AShM is spotted the gun is fired from proper angles keeping in mind the deviations so missile is always in the middle of the cone.The aim of the GG system is to create a fire swarm , a curtain of steel.So deviations are actually a good thing.Its like an MBRL an area weapon.No army comander wants all rockets of
SMERCH to land at the same spot.

One possible advantage of tracking outgoing shells is if the shells travel differently due to wind or choppy seas , then the pattern can be calculated and the weapon adjusted accordingly.

But given the amount of calculations to be performed , I doubt whether the claims are true.
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Re: Klub ASCM and Kilo Upgrades

Post by Raman »

The above explanation doesn't make sense to me.

If the shells from a CIWS consistently missed
in a specific way (say due to a strong wind or
a callibration error), no amount of "shoot-and-
wait-for-a-plume" is going to get the incoming
missile down.

I would expect that a true closed loop system
measures the relationship of the tracking vehicle
(i.e., the shells) to the target vehicle (the
missile) and make adjustments based on this
measured difference. If you're only tracking
the target and not the relationship of your
vehicle to the target, I would think that your
system is open-loop.

Of couse, if the tracking equipment is on the
kill vehicle itself (like a guidance package
on a missile), any tracking measurement
automatically is measuring the relative position.
The issue here is that the tracking equipment is
on the ship, so just knowing where the target is
does not comprise a closed loop system.

Using the satellite analogy above, it is
equivalent to just knowing where the orbit is,
and not the relationship of the satellite
position and orientation to the orbital path.

Thus, I think your characterization of closed
loop systems as:
sense object ---> give correction --> ...
is incorrect. It should be:
sense error ---> give correction --> ...

Also, is it necessary to track each and every
shell of the CIWS for a true closed loop system?
Can't the shells be tracked/modeled in aggregate
as a "stream" for this application?

++Rajesh
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

Of course the tracking is done as a stream , tracking individual bullets is impossible!!! If the close loop system can have super fast reaction/resonse time then nothing like it, but in most cases the total time lag is too big to be effective.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

When I said sense object I meant sense error only.That is sense object to find out the error.Frankly speaking I dont see why you should track the out going shells.You know the trajectory a shell takes when it is fired , especially when distances are short as 1-2 km .
Also for a shell with a muzzle velocity of 1250 m how much can the wind affect ? At any rate the basic philosophy of a CIWS is brute force and not smart calculations.An American weapons expert lamented that the phalanx has only 2.5 secs to calculate the firing solution when engaing a Yakhont missile.At such short times , the best thing is brute force.It didnt occur to me you could track it as a stream but still its a distrction you can avoid.One can understand tracking shells if its Radar directed artillery , firing at around 100-200 rounds per minute , but when you are firing 100 rounds per second , its obvious you don't care about accuracy.
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

The point is Russian CIWS is no way inferior to Phalanx or other western systems.The West is good in packaging and may say certain things to impress the world , but that dosent make the others inferior.We have to reconcile to a certain amount of inferiority in electronics and software when we go for Russian systems.But they make up for that in hardware.As long as a weapon serves its purpose , it dosent matter how.
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

A closed loop system is better than a CIWS, that much is obvious. But mastering closed loop system is important to India , especially if we want to develop a capable ABM. Developers working on Trishul will achive nirvana if we can achive faster reaction rate and responce to it.

By the way in digital electronics 2.5 sec is a lifetime. The problem is to develop an equally fast mechanical, electronic or Chemical system to respond. (By chemical i ment combustion time for missile's)
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Re: Klub ASCM and Kilo Upgrades

Post by Raman »

Harry,

I am no expert in weapon systems and ballistics, so I might be inclined to agree with you --- except for the fact that you contradict yourself. I quote you below:
Frankly speaking I dont see why you should track the out going shells.You know the trajectory a shell takes when it is fired , especially when distances are short as 1-2 km .
Also for a shell with a muzzle velocity of 1250 m how much can the wind affect ?
wheras in your previous post you said:
One possible advantage of tracking outgoing shells is if the shells travel differently due to wind or choppy seas , then the pattern can be calculated and the weapon adjusted accordingly.
The whole distinction between an open-loop system and a closed-loop system is assuming the position/orientation of the kill vehicle relative to the target vs. measuring the actual position/orientation. I repeat: just tracking the target and assuming the position of the kill vehicle is not closed-loop.

Going by your definition of closed-loop system, it is impossible for an open-loop system to track and manouver to a moving target (because this scheme is what you call a closed-loop system).
When I said sense object I meant sense error only.That is sense object to find out the error.
If you assume the position of the kill vehicle and track only the target, it is not possible to measure error: you can only estimate it with some bounds. This is the whole point of closed-loop systems.

However, I am inclined to agree with your broad hypothesis that Kashtan can be as effective as Phalanx --- it's only the minor technicalities and terminology that I disagree with. :)

Nathan,
A closed loop system is better than a CIWS, that much is obvious.
I'm not sure what you mean by the above: "closed-loop" is a basic scheme in control systems, and "CIWS" is a weapon system --- they are not directly comparable in any meaningful way. Did you mean " ... is better for a CIWS ..."??

Cheers,

++Rajesh
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

I think its time some expert comes and clears up the mess.

Also in this case , is it not the Gatling Gun that is the kill vehicle ? The Shells follow 99 % predictable trajectory.
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Re: Klub ASCM and Kilo Upgrades

Post by Raman »

I think its time some expert comes and clears up the mess.
... or alternatively use our friend google.

FAS on Phalanx from http://www.fas.org/man/dod-101/sys/ship/weaps/mk-15.htm:
The unique closed-loop fire control system that tracks both the incoming target and the stream of outgoing projectiles gives CIWS the capability to correct its aim to hit fast-moving targets, including ASMs.
Also, with respect to:
Also in this case, is it not the Gatling Gun that is the kill vehicle ? The Shells follow 99 % predictable trajectory.
The gun is no more the "kill-vehicle" for a CIWS than a launch pad is for an ICBM --- the fired projectile is the kill vehicle. Evidently, the "99% predictable trajectory" is not good enough for Phalanx.

Cheers,

++Rajesh
John
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Re: Klub ASCM and Kilo Upgrades

Post by John »

Well i think this closed loop discussion has gotten out of hand :) for all we know IN AK-630 could very well be closed loop. If u recall P16A/Brahmaputra frigate uses TMX-KA as the fire control system for its AK-630 and Oto 76mm which is capable of tracking outgoing shells.
harishn
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

Rajesh.. sorry about my earlier statement. CIWS stands for Close In Weapons System , which by definition means a Closed loop System. Close loop is always bettre than open loop, provided we can install an equally fast mechanical system with great responce time.
Harry Van
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Re: Klub ASCM and Kilo Upgrades

Post by Harry Van »

Ok guys , tell me about this.

An Indian soldier in broad daylight shoots at a Pakistani soldier attemting to cross the border.The Puki ducks and runs helter skelter , our soldier keeps him in his sights and keeps shooting at him .

Is the above example a closed loop system or open loop system ?
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

Harry the example u gave was of a Man in loop system. :cool:
shiv
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Re: Klub ASCM and Kilo Upgrades

Post by shiv »

My 2 paise:

Closed loop:

"You (idiot) have performed an illegal operation and Windows is now shutting down and erasing your last 16 hours of work"

Man in loop:

Cannot find C:
Abort, Retry, Slap nearest bystander
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Re: Klub ASCM and Kilo Upgrades

Post by Roop »

Close In Weapons System , which by definition means a Closed loop System.
Nonsense! It means nothing of the kind.
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Re: Klub ASCM and Kilo Upgrades

Post by Raman »

Originally posted by harryvandeusan:
Ok guys , tell me about this.

An Indian soldier in broad daylight shoots at a Pakistani soldier attemting to cross the border.The Puki ducks and runs helter skelter , our soldier keeps him in his sights and keeps shooting at him .

Is the above example a closed loop system or open loop system ?
Harry --- my last post on this subject (I promise!) This thread has been completely hijacked by our discussion.

When a soldier fires a gun using the sight and the bullet misses, does the soldier know by how much the bullet missed?

In some cases, yes --- one can see a plume of dust where the bullet hit the ground. When this happens, the soldier can correct the observed error because he knows by how much he missed. This is why strike pilots will "walk" a stream of bullets onto the target during strafing runs instead of just putting the sights on the target and firing. In these cases only (i.e., when the error can be observed) one can claim that the soldier-gun-target complex is an (informal) closed-loop system.

In many other cases, there is no indication by how much the bullet missed by --- there is no smoke trail, no dust plume, nothing. Nothing but a missed target. Now what do you do? Just repeat what you just did? What if you miss again?
And again, and again? However, you might try to spin it, this case is an (informal) open-loop system.

It doesn't matter if the bullet's trajectory is "99% predictable". Predictable under what conditions of wind, atmospheric density, humidity, propellant purity, sight callibration accuracy, barrel wear, etc.? Why do artillery shells miss at all? Why didn't the satellite move to the exact slot even though you provided all the instructions that would take it there as predicted by your satellite mechanics model? Minor variations in any one of thousands of variables can cause deviations.

The bottom line is: IT DOESN'T MATTER --- the desired outcome was not achieved, and if you don't know exactly what the error is, you can't correct for it.

A parting thought: why do human operated anti-aircraft guns use tracer rounds at night (and sometimes even during day time)? Answer: To let the gun crew know by how much they are missing the target --- i.e., measure the error. Those tracer rounds let the crew operate as a closed-loop system instead of an open-loop system.

Cheers,

++Rajesh
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Re: Klub ASCM and Kilo Upgrades

Post by Arun_S »

harryvandeusan
I have always wondered why a SHORAD like Trishul was done as a radar guided missile.For such short ranges , IR guidance is the best and in fact the safest.
Anti-Missile Defense requires the best possible:

1. Robust long range detection of incoming missile. No doubt that RADAR technology is the only one that is applicable, as against IR search that hardly gives enough warning time.

2. Very high acceleration Anti-Missile motor, to ensure the interception takes place further away from the ship.

3. Very accurate targeting and flight control system. That again pre-cludes use of IR sensors that only provides 2-D target information missing the citical range information that makes impossible a useful control system to ensure interception.

Interception is made worse if the incoming missile speed is fast, this is due to practical limits of RADAR/detection system in accurately predicting the tarjectory. That is the reason to supersonic trend of modern Anti-Shipping missiles.

The above shows that RADAR based survilalnce and target homing is pivitol to intercepting an incoming missile.

IIRC no IR guided missile (SAM or Air to Air) is used for head on interception.
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Re: Klub ASCM and Kilo Upgrades

Post by harishn »

It must be pointed out that a Man in Loop system is essentially a closed loop system. Replace the man with a compute , his eyes with a radar and his arms with a mechanical gun and u have a CIWS. The whole objective of is to remove the 'unreliable' and 'inefficient' man with an 'reliable and efficient' system :) .

One other point of importance is that in the above example both the attacker and the defence personal represent a Close Loop System. This is usually not the case unless the attacking missile is capable of dodging bullets and ABM:). The future catogary of cruise/ballistic missiles is supposed to have this capability but till then the above example is not good enough. Though i must say that it was a good attempt to simplify control systems to the layman. Maybe this should be my last post on control sytems too :D .
Nonsense! It means nothing of the kind.
please explain.
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