How effective are CIWS?

Unread postPosted: 28 Apr 2019, 15:59
by michaelemouse
Is there some open intel or educated guesses about the probability of kill of something like the Phalanx against anti-ship missiles, given roughly equal technology levels?

Any idea what it might be for missile-based CIWS?

Re: How effective are CIWS?

Unread postPosted: 28 Apr 2019, 16:22
by sferrin
Christ It Won't Shoot.

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 08:53
by hornetfinn
It's really difficult to say as no CIWS system has actually shot down a missile in actual combat. In testing they have been successful, but tests are always done in very calculated and safe way against individual targets. In real combat things can be quite more complex and difficult as enemy will do their best to make things very difficult. So they can do things like launch multiple missiles with different flight paths but simultaneous impact time. So many missiles will be coming from different directions at about the same time. This is where missile based systems are better due to their much longer reach and ability to engage multiple simultaneous targets. It's really difficult to assess their effectiveness against modern anti-ship missiles in real world. In testing against target missiles they have worked pretty good recently, but it's impossible to know how close to real missiles those target missiles are.

I'd bet modern missile based systems would work pretty well against even modern missiles, especially against small number of missiles. Against larger number of missiles chances of killing every single one would diminish and lossess would be likely. Gun based CIWS are just last ditch defenses to cover the minimum range of missiles. They might be able to shoot down individual leakers but I would bet the ship would get damaged from the missile debris. Of course that is still preferable compared to eating fully functioning warhead and missile with fuel in it.

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 13:19
by hornetfinn
I'd also say that against older and larger missiles like Silkworms both the missiles and guns are likely pretty effective. Those missiles have huge signatures and fly at higher altitude and basically fly in straight line during the final approach. So they are easily detected, tracked and engaged with weapons.

Truly modern missiles are much smaller and have very low radar and IR signatures. They also fly at very low altitudes trying to hide in sea clutter and can maneuver pretty well during final approach. A lot depends on how early the sensors in ship can detect them and how reliably they can track them. I think if the missile can be tracked, then it will likely get shot down. Of course swarming several missiles will increase chances of leaking at least one through.

Of course ships will also try to maneuver and employ both active and passive countermeasures (EW and chaff for example).

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 14:50
by zero-one
well its a bit difficult to answer. what exactly do you mean by "given roughly equal technology levels?" Is it like comparing the CWIS systems of this era to the cruise missiles of the same era?

The RIM-116 is probably one of the best missile based CIWS of the modern era
the SSM-700K can be considered the most modern iteration of the 80s era Harpoon
the AGM-158C is a very advanced stealth anti ship cruise missile with very high Situational awareness and Artificial intelligence.

I think the RIM-116 will enjoy more success against the SSM-700K, although they are both in the same era as the AGM-158C

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 15:00
by sdkf251
I seem to remember long time ago the seawolf was able to intercept incoming missiles during the Falkland war. Not sure how it is classified, but I think it is a CIWS of sorts? It was so long ago that data should be available by now.

Hope this helps

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 16:12
by pmi
hornetfinn wrote:It's really difficult to say as no CIWS system has actually shot down a missile in actual combat.


HMS Gloucester launched a Sea Dart to destroy a Silkworm launched at the Missouri during Desert Storm. Ironically the Phalanx on the USS Jarrett targeted Missouri's chaff instead (with a few rounds hitting Mo)....

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 20:20
by sferrin
pmi wrote:
hornetfinn wrote:It's really difficult to say as no CIWS system has actually shot down a missile in actual combat.


HMS Gloucester launched a Sea Dart to destroy a Silkworm launched at the Missouri during Desert Storm. Ironically the Phalanx on the USS Jarrett targeted Missouri's chaff instead (with a few rounds hitting Mo)....


Sea Dart wasn't a CIWS system.

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 22:19
by quicksilver
I once observed a CIWS (at sea) shoot a target off of the tow wire...

Re: How effective are CIWS?

Unread postPosted: 29 Apr 2019, 23:51
by sferrin
quicksilver wrote:I once observed a CIWS (at sea) shoot a target off of the tow wire...


Phalanx have shot down 5" rounds in testing as well.

Re: How effective are CIWS?

Unread postPosted: 30 Apr 2019, 01:51
by count_to_10
I heard a story about two phalanx firing at the same target and then following each other’s stream of bullets back toward each other.

Re: How effective are CIWS?

Unread postPosted: 30 Apr 2019, 02:36
by sferrin
count_to_10 wrote:I heard a story about two phalanx firing at the same target and then following each other’s stream of bullets back toward each other.


I've heard several odd stories as well. Phalanx trying to shoot down parts of previously dispatched target. Phalanx trying to lock onto rotor-blade tips. Part of the learning process I gather.

Re: How effective are CIWS?

Unread postPosted: 30 Apr 2019, 06:54
by hornetfinn
sferrin wrote:
count_to_10 wrote:I heard a story about two phalanx firing at the same target and then following each other’s stream of bullets back toward each other.


I've heard several odd stories as well. Phalanx trying to shoot down parts of previously dispatched target. Phalanx trying to lock onto rotor-blade tips. Part of the learning process I gather.


These things happen with automated air defence gun systems. Rotor-blade tips are very attractive for fire-control radar as they give very nice doppler returns for it. Those doppler returns can be easily filtered out, but in most systems those returns are wanted. Helos are difficult to track otherwise as they are very slow moving or stationary targets at low altitude which means they themselves don't give good doppler returns. This makes them difficult to separate from ground or sea clutter. I'm sure helos are also one potential (although not always very likely) target even for Phalanx.

Fire control radars following stream of bullets or towing cable is very normal. Phalanx especially has huge rate of fire and the stream is very continuous. It's basically like a cable for the fire control radar which means it's a very long and narrow target. However the radar doesn't really see that, but sees some part of the stream or cable as target which it tries to follow. The cable or stream of bullets however has very unstable radar signature and thus the "target" moves all the time in that stream or cable. I've personally fired at a target drogue and couple of seconds later the target tug (towing aircraft) is in the sights. The radar had followed the cable and target tug was a juicy target for it. Luckily there are many safeguards to prevent shooting down the target tug, but pilot in that thing must really have steel nerves in any case.

Re: How effective are CIWS?

Unread postPosted: 01 May 2019, 11:59
by eloise
I read a study about CIWS PK vs maneuver target and PK vs non maneuver target
Unfortunately, i forget to save the source and now i can't find it :bang:

Re: How effective are CIWS?

Unread postPosted: 01 May 2019, 13:21
by madrat
I remember something about Goalkeeper advertising pointing out the failings of comparable CIWS that had a lot of information. To me their data suggested the system needed intelligence more so than their system, but that's me reading in between the lines.

Re: How effective are CIWS?

Unread postPosted: 01 May 2019, 13:51
by quicksilver
“Phalanx trying to shoot down parts of previously dispatched target.”

Yep. Have seen it w my own eyes.

Re: How effective are CIWS?

Unread postPosted: 01 May 2019, 17:47
by marauder2048
hornetfinn wrote:
sferrin wrote:
count_to_10 wrote:I heard a story about two phalanx firing at the same target and then following each other’s stream of bullets back toward each other.


I've heard several odd stories as well. Phalanx trying to shoot down parts of previously dispatched target. Phalanx trying to lock onto rotor-blade tips. Part of the learning process I gather.


These things happen with automated air defence gun systems. Rotor-blade tips are very attractive for fire-control radar as they give very nice doppler returns for it. Those doppler returns can be easily filtered out, but in most systems those returns are wanted. Helos are difficult to track otherwise as they are very slow moving or stationary targets at low altitude which means they themselves don't give good doppler returns. This makes them difficult to separate from ground or sea clutter. I'm sure helos are also one potential (although not always very likely) target even for Phalanx.



Blade modulation is about the only thing you have for a stationary helicopter trying to hide in sea-clutter.

"Coherent Data Collection Efforts in Support of Phalanx"

https://www.jhuapl.edu/techdigest/TD/td1803/rzerou.pdf

Re: How effective are CIWS?

Unread postPosted: 03 May 2019, 01:59
by count_to_10
So, if you want to know what the military would like to have instead of phalanx, look up mad fires.
https://www.darpa.mil/program/multi-azi ... ent-system

Re: How effective are CIWS?

Unread postPosted: 03 May 2019, 12:07
by hornetfinn
count_to_10 wrote:So, if you want to know what the military would like to have instead of phalanx, look up mad fires.
https://www.darpa.mil/program/multi-azi ... ent-system


Sounds a bit like Oto Melara 76 mm with DART ammunition.

Re: How effective are CIWS?

Unread postPosted: 03 May 2019, 12:33
by madrat
Battlespace management technology back in the 90's was promised to make AI integration much simpler.

I cannot imagine they were wrong about that. Surely CIWS in 2019 is infinitely more aware of targets, no longer just using smudge lights based on radar technology to illuminate the inbound. Surely the EODAS technology is applied to ships only on steroids compared to aircraft. You can afford EODAS spherical coverage with much longer reaching lenses.

Re: How effective are CIWS?

Unread postPosted: 03 May 2019, 22:29
by marauder2048
madrat wrote:Battlespace management technology back in the 90's was promised to make AI integration much simpler.

I cannot imagine they were wrong about that. Surely CIWS in 2019 is infinitely more aware of targets, no longer just using smudge lights based on radar technology to illuminate the inbound. Surely the EODAS technology is applied to ships only on steroids compared to aircraft. You can afford EODAS spherical coverage with much longer reaching lenses.



The destroyers do incorporate the CIWS (Phalanx or SeaRAM) radar tracks into the CEC composite tracks;
Ku-band has some really nice properties in certain propagation conditions. The optical horizon being shorter
than the RF horizon probably means that a major use of infrared would be in kill-assessment since its
better angular resolution gives it an advantage in discriminating debris from say a trailer in a stream raid.

Re: How effective are CIWS?

Unread postPosted: 07 May 2019, 10:22
by zero-one
meaning to ask this for a while now, but I'm wondering if it deserves its own thread.
What are the candidates for the most effective ASuW missile.

To me, its the AGM-158C. Its main strengths include VLO technology, very long range and low sea skimming capabilities and most importantly it is the only missile I know that has its own ESM and RWR. This means that it is the 1st missile of its kind that actually knows if it is being tracked and targeted by CIWS or other defenses.

Sure, other ASuW weapons are much faster, but they are flying blind against anti missile defenses and once they start executing their end game maneuvers which are pre-programmed and not designed to adjust to enemy defenses, they will throw all that speed out the window. Can the Brahmos and Klub missiles maneuver at supersonic speeds?

So with a premise like this, it makes sense that the USN chose Stealth and AI over raw speed when they chose the LRASM over faster counterparts. However this also suggest that modern CIWS and missile defenses are so effective that speed just won't cut it. In that case the old Harpoon and other similar weapons will not have very good Pk numbers against modern ships.

Re: How effective are CIWS?

Unread postPosted: 07 May 2019, 11:14
by knowan
zero-one wrote:Can the Brahmos and Klub missiles maneuver at supersonic speeds?


Probably, but their g-limit is unlikely to be high enough to allow for any significant manoeuvring at supersonic speeds.


hornetfinn wrote:
count_to_10 wrote:So, if you want to know what the military would like to have instead of phalanx, look up mad fires.
https://www.darpa.mil/program/multi-azi ... ent-system


Sounds a bit like Oto Melara 76 mm with DART ammunition.


57mm according to this article: https://www.navalnews.com/event-news/sa ... d-testing/

I wonder if this played a part in selection of a 57mm gun for the FFG(X)?

Re: How effective are CIWS?

Unread postPosted: 07 May 2019, 13:03
by sferrin
knowan wrote:I wonder if this played a part in selection of a 57mm gun for the FFG(X)?


Doubt it. The gun is already on the LCS and elsewhere.

Re: How effective are CIWS?

Unread postPosted: 07 May 2019, 17:30
by marauder2048
knowan wrote:I wonder if this played a part in selection of a 57mm gun for the FFG(X)?


It was another guided round:


Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 00:27
by marauder2048
knowan wrote:
zero-one wrote:Can the Brahmos and Klub missiles maneuver at supersonic speeds?


Probably, but their g-limit is unlikely to be high enough to allow for any significant manoeuvring at supersonic speeds.


And GQM-163A isn't the least bit weight optimized.

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 00:32
by sferrin
marauder2048 wrote:
knowan wrote:
zero-one wrote:Can the Brahmos and Klub missiles maneuver at supersonic speeds?


Probably, but their g-limit is unlikely to be high enough to allow for any significant manoeuvring at supersonic speeds.


And GQM-163A isn't the least bit weight optimized.


But is 12Gs at Mach 2.5 really much of a turn? Here's a Vandal getting shot down by ESSM years ago performing a 10G weave at Mach 2+

(The good stuff starts at 3:30)

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 01:11
by gc
zero-one wrote:meaning to ask this for a while now, but I'm wondering if it deserves its own thread.
What are the candidates for the most effective ASuW missile.

To me, its the AGM-158C. Its main strengths include VLO technology, very long range and low sea skimming capabilities and most importantly it is the only missile I know that has its own ESM and RWR. This means that it is the 1st missile of its kind that actually knows if it is being tracked and targeted by CIWS or other defenses.

Sure, other ASuW weapons are much faster, but they are flying blind against anti missile defenses and once they start executing their end game maneuvers which are pre-programmed and not designed to adjust to enemy defenses, they will throw all that speed out the window. Can the Brahmos and Klub missiles maneuver at supersonic speeds? .


Yep i read an analysis on Janes. Supersonic ASMs are limited to sctive radar seekers due to the heating of the nose cone at high speeds and low altitude. Active seekes will give its presence and location away the moment it comes on. The thing i like most about LRASMs and NSMs is its passive RF and iR seekers. The only way a ship can get warning is by radiating. And by forcing them to radiate continuously, they give away their location, which is the most important step in surface warfare kill chain. And radiating doesnt protect the ship at the end of the day due to the VLO designs of such missiles.

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 04:34
by marauder2048
sferrin wrote:
But is 12Gs at Mach 2.5 really much of a turn? Here's a Vandal getting shot down by ESSM years ago performing a 10G weave at Mach 2+



For a conventional (non-airbursting, unguided) single mount, gun-based CIWS, absolutely.

Even for large caliber (76mm) dual-mounts firing airburst rounds some of the analysis I've read is
pretty sobering for 10G targets.


"Limitations of Guns as a Defence against Manoeuvring Air Weapons"
(my OCR'ed version attached).

https://apps.dtic.mil/dtic/tr/fulltext/u2/a426717.pdf

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 12:10
by michaelemouse
zero-one wrote:meaning to ask this for a while now, but I'm wondering if it deserves its own thread.
What are the candidates for the most effective ASuW missile.

To me, its the AGM-158C. Its main strengths include VLO technology, very long range and low sea skimming capabilities and most importantly it is the only missile I know that has its own ESM and RWR. This means that it is the 1st missile of its kind that actually knows if it is being tracked and targeted by CIWS or other defenses.

Sure, other ASuW weapons are much faster, but they are flying blind against anti missile defenses and once they start executing their end game maneuvers which are pre-programmed and not designed to adjust to enemy defenses, they will throw all that speed out the window. Can the Brahmos and Klub missiles maneuver at supersonic speeds?

So with a premise like this, it makes sense that the USN chose Stealth and AI over raw speed when they chose the LRASM over faster counterparts. However this also suggest that modern CIWS and missile defenses are so effective that speed just won't cut it. In that case the old Harpoon and other similar weapons will not have very good Pk numbers against modern ships.



I suggest that it mainly comes down to reaction time. Can you reduce reaction time more through stealth/jamming/decoys or through speed? Bear with me through this simplified illustration; If I try to provide an exhaustive illustration using entire militaries acting against each other, I'll need to write a PhD thesis:

If the radar horizon is, say, 30km and you're going at 300m/s, that means the target has 100 seconds of reaction time from the moment it identifies the missile as a valid threat to the time it impacts the target. If you go at 600m/s, the target will have 50 seconds of reaction time. If you go at 1200m/s, the target will have 25 seconds. The problem with increasing speed is that, especially if you're flying at low altitude, drag increases exponentially as a function of velocity so you need ever larger amounts of propellant and ever more powerful engines.

The question then becomes: How much can you reduce enemy reaction time using electronic warfare elements like stealth, jamming, decoys or other means? More knowledgeable people than I may be able to give us partial answers which we can put together.

My guess is that Russia and China are betting on speed not because that's the most effective option but because the US is a head above them when it comes to information warfare so they have to make up for lack of smarts with brute force. That's how Arab militaries try to win wars and it hasn't worked out for them against the Americans, the Israelis or the Chadians.

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 19:32
by sferrin
marauder2048 wrote:
sferrin wrote:
But is 12Gs at Mach 2.5 really much of a turn? Here's a Vandal getting shot down by ESSM years ago performing a 10G weave at Mach 2+



For a conventional (non-airbursting, unguided) single mount, gun-based CIWS, absolutely.

Even for large caliber (76mm) dual-mounts firing airburst rounds some of the analysis I've read is
pretty sobering for 10G targets.


"Limitations of Guns as a Defence against Manoeuvring Air Weapons"
(my OCR'ed version attached).

https://apps.dtic.mil/dtic/tr/fulltext/u2/a426717.pdf


Jesus, I guess I need to pay attention. Guns are terrible solutions for dealing with swarms. isn't that what they're trying to do with MAD-FIRES though? :?

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 21:28
by madrat
Guns are the method of delivery vehicle not the mode of guidance.

Re: How effective are CIWS?

Unread postPosted: 08 May 2019, 23:06
by sferrin
madrat wrote:Guns are the method of delivery vehicle not the mode of guidance.


Even Super Rapido with DART:



and two or three of them in the case of the Horizon class. . . Well, I wouldn't want to be in an Iranian speedboat but against a supersonic missile? I'd rather have Goalkeeper or SeaRAM.

1920px-Andrea_Doria_(D_553).jpg

Re: How effective are CIWS?

Unread postPosted: 09 May 2019, 08:59
by hornetfinn
High speed is good for reducing the target reaction time, but at the same time has some drawbacks. High speed usually means higher flight altitude is required to avoid hitting the waves. This gives somewhat longer radar horizon and makes it easier to pick up the missile early. So that takes aways some advantage in reaction time. High speed also means much higher IR signature which makes it easy for IR sensors to detect the missile early. Radar signature is also likely much higher as high speed makes it far more difficult to reduce RCS. Shaping needs to t

Other drawback of high speed is that missile is necessarily much larger or has shorter range and smaller warhead. That also makes it easier to detect and lowers the number of missiles in any engagement.

IMO, stealth and slow speed system is superior overall. But that requires the capability to produce such high level stealth to make detection and engagement very difficult. High speed missiles are easier to make and can make defending against them pretty difficult. Especially for CIWS systems as they can only engage one target at a time and engaging other targets takes some time.

Re: How effective are CIWS?

Unread postPosted: 09 May 2019, 09:41
by milosh
zero-one wrote:To me, its the AGM-158C. Its main strengths include VLO technology, very long range and low sea skimming capabilities and most importantly it is the only missile I know that has its own ESM and RWR. This means that it is the 1st missile of its kind that actually knows if it is being tracked and targeted by CIWS or other defenses.

Sure, other ASuW weapons are much faster, but they are flying blind against anti missile defenses and once they start executing their end game maneuvers which are pre-programmed and not designed to adjust to enemy defenses, they will throw all that speed out the window. Can the Brahmos and Klub missiles maneuver at supersonic speeds?


Soviet P-500/700/1000 all have internal jammer. I don't know for P-800 (Onix/Brahmos) but probable it have jammer also.

Klub isn't supersonic there was proposed two stage variant which would be stealthy supersonic stage for thermal phase but I don't think it was developed because they start working in that time on Zircon. Indians mentioned Brahmos-2 rcs is lot smaller then Brahmos-1 and that is only from shape, not some exotics mentioned by Russians lately.

Re: How effective are CIWS?

Unread postPosted: 09 May 2019, 13:08
by sferrin
milosh wrote:Soviet P-500/700/1000 all have internal jammer.


That's only going to help the defending missile if it's designed to home in on RF energy. Like this one:

C43g3pDWcAUSWiT.jpg

Re: How effective are CIWS?

Unread postPosted: 09 May 2019, 13:23
by hornetfinn
No wonder RIM-116 was fielded at about the same time as P-700 and some other advanced Soviet anti-ship missiles which all used active radar guidance and which also possibly had ECM equipment. RIM-116 definitely gave superior multi-target capability and longer reach than CIWS systems. I think even if Phalanx managed to kill P-700 missile, the ship would likely be pretty seriously damaged due to size and speed of that missile.

Re: How effective are CIWS?

Unread postPosted: 09 May 2019, 23:02
by marauder2048
sferrin wrote:
Jesus, I guess I need to pay attention. Guns are terrible solutions for dealing with swarms. isn't that what they're trying to do with MAD-FIRES though? :?


Ah. MAD-FIRES and Alamo are both guided rounds. So the probability of hit is no longer just a function of
gun dispersion, time of flight and burst radius in the case of airburst munitions. Guidance should dramatically
reduce the number of rounds that need to be expended to achieve a hit which translates to tolerable
rates of fire for medium caliber mounts.


hornetfinn wrote:No wonder RIM-116 was fielded at about the same time as P-700 and some other advanced Soviet anti-ship missiles which all used active radar guidance and which also possibly had ECM equipment


SM-2 Block IIIb (with IR seeker) was also developed specifically to counter ASCMs with terrain-bounce jammers.

Re: How effective are CIWS?

Unread postPosted: 10 May 2019, 02:05
by madrat
They probably aren't far off from giving mid-course re-targeting of outbound gun-deployed smart rounds. It seems like they pretty much evolve all uses of guidance technology across the spectrum of weapons over time. Being able to re-purpose a round after target disintegration would be a natural next step.

Re: How effective are CIWS?

Unread postPosted: 10 May 2019, 11:54
by sferrin
madrat wrote:They probably aren't far off from giving mid-course re-targeting of outbound gun-deployed smart rounds. It seems like they pretty much evolve all uses of guidance technology across the spectrum of weapons over time. Being able to re-purpose a round after target disintegration would be a natural next step.


I think this is generally what they have in mind when the USN talks about using hypersonic rounds, developed for railguns, in the Anti missile mode.

https://www.baesystems.com/en-us/produc ... ectile-hvp

image.jpg


img.png

Re: How effective are CIWS?

Unread postPosted: 11 May 2019, 02:50
by count_to_10
The trick up to recently has been making a guidance system rugged enough to survive gun launch, but that problem appears to have been solved. Warhead triggering is the holy grail, but they may have to settle for less.

Re: How effective are CIWS?

Unread postPosted: 11 May 2019, 04:04
by popcorn
Not quité CIWS but the Navy should soon be fielding cost-effective guided HVP rounds fired from 5-inch deck cannon to provide an additional defensive layer be airborne threats.

Re: How effective are CIWS?

Unread postPosted: 12 May 2019, 22:40
by marauder2048
popcorn wrote:Not quité CIWS but the Navy should soon be fielding cost-effective guided HVP rounds fired from 5-inch deck cannon to provide an additional defensive layer be airborne threats.


HVP (now GLGP) definitely seems to have gone beyond "classic" CIWS.

If you look at the recent gun-launched guided projectile RFI they are looking at a combination of midcourse guidance
from SPY, 2-way datalink and an active seeker to permit OTH terminal operation.
To the point above regarding warhead triggering, an active seeker should help with fuze timing.

https://www.fbo.gov/index?s=opportunity&mode=form&id=9c3cc7ad29b7167ab4014672131ef146&tab=core&_cview=1