Phalanx CIWS garners a lot of criticism from naval commentators for reasons that I generally find to be invalid. Probably the number one criticism of the Phalanx CIWS is the notion that it will merely break up an attacking missile and the resulting debris will, guaranteed, continue on to hit the ship, apparently causing as much damage as the intact missile would (or maybe more?!), in the minds of critics. In fact, among naval commentators, this concept of debris striking the ship has taken on mythic proportions. It’s time to examine this concept and see if it’s true or not.
CIWS Purpose
Let’s start by recalling what the purpose of a close in weapon system is. It is, by definition, the last, ultimate, final chance to prevent an intact, live missile from hitting, penetrating, and exploding inside the ship. Thus, the job of the close in weapon system is to ‘inactivate’ the attacking missile so that it cannot explode in the ship. Ideally, that will be as a result of the physical destruction of the attacking missile. Less ideal, but perfectly acceptable given the alternative, is destruction of the warhead. If some scattered, slower, debris impacts the ship that's far preferable to an intact, exploding missile hitting the ship.
Debris
As far as missile debris hitting the ship, I know of no real world or exercise example of such an occurrence. The theoretical possibility exists but I've seen nothing to suggest it's a significant danger. In fact, there are a few documented exercise examples of CIWS re-engaging debris.
Even a theoretical consideration of the debris strike scenario suggests that it is unlikely. With the main body of the attacking missile hit and destroyed to the point of generating sizable debris, the physics of the scenario suggests that the debris is far more likely to have been blasted onto an altered path, upward, downward, or sideways, away from the targeted ship. The likelihood of debris coming out of an explosion and continuing on the exact same previous path is remote. The force of the explosion almost guarantees that can’t happen since the explosion would occur in front of, or at the front of, the missile and the explosion would impel the rest of the missile debris backwards, sideways, up, or down. The explosion, itself, therefore, acts as a shield or deflector to alter the path of any generated debris. Consider the following conceptual drawing which illustrates how the explosion from a CIWS intercept of an attacking missile (the arrow) scatters the debris up, down, left, and right but not on the missile's original path. Instead, the debris pieces are deflected off the path to the defending ship.
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Conceptual CIWS Intercept Attacking Missile is the Arrow Ship is to the Right |
Further, any debris, by definition, will be misshapen, unpowered, and no longer aerodynamic. That means that whatever path it's on it will very quickly lose speed and gravity will further alter its path downward, away from the ship.
In the absolute worst case of a piece somehow continuing on a path that intersects the ship, the piece will be substantially smaller (less mass) than the original attacking missile and, being unpowered, will be very much slower than the original attacking missile and will be decelerating very quickly due to friction and the drag from its non-aerodynamic shape.
Kinetic Energy
One of the arguments that debris myth-holders maintain is that the kinetic energy of the debris pieces will be sufficient to vaporize or severely damage/sink the ship even without a warhead. Of course, as naval analysts and well educated products of our public school system, we know that kinetic energy is the product of two factors: mass and speed:
kinetic energy = ½ * mass * velocity squared
k.e. = ½ * m * v2
Since debris, by definition, is smaller pieces of the original missile, the mass of any given piece will be substantially reduced compared to the original, intact missile, thereby reducing the kinetic energy of the debris. As we noted, the speed of the debris will be hugely reduced and slowing the entire time until impact on the ship. Thus, the velocity term (being a squared effect!) will be hugely reduced. The result is that the kinetic energy of a debris piece will be nearly insignificant as far as inflicting significant damage. Thus, the fears of the ship being vaporized by the kinetic energy of debris pieces are unfounded. Let’s check that by running through a couple of examples.
Chinese C-802/YJ-83 Missile
Let’s consider a common anti-ship missile like the Chinese C-802/YJ-83 series. From Wikipedia,
mass = 715 kg
velocity = Mach 0.9 = 684 mph = 306 m/s
so,
k.e. = 0.5 * m * v2
k.e. = 0.5 * 715 kg * (306 m/s)*(306 m/s)
k.e. = 33,474,870 (kg*m2)/s2 = 33,474,870 J
By comparison, a kg of TNT releases 4,184,000 J. Thus, the k.e. of the original, intact missile is equivalent to around 8 kg of TNT. To put that into context, a U.S. Navy lightweight Mk54 torpedo has a warhead weight of 44 kg (we'll assume it's TNT even though it isn't). That means the missile would have kinetic energy equal to 18% of the explosive energy of a Mk54 lightweight torpedo - not enough to even be noticed, by comparison, and certainly not a one-shot kill/vaporization due to kinetic energy alone.
Of course, that calculation was for an intact missile - with a full fuel load, by the way; the missile would actually have used up much of its fuel and the mass would be lower resulting in even less kinetic energy. Now, let’s repeat the calculation for a debris fragment.
C-802 Debris
For sake of discussion, let’s assume a piece of debris 1/10th of the mass of the original missile and a velocity at impact of ½ the original speed. That gives us,
mass = 0.1 * 715 kg = 71 kg
velocity = 0.5 * Mach 0.9 = Mach 0.45 = 342 mph = 153 m/s
so,
k.e. = 0.5 * 71 kg * (153 m/s)*(153 m/s)
k.e. = 831,019 (kg*m2)/s2 = 831,019 J
By comparison, a kg of TNT releases 4,184,000 J. Thus, the k.e. of the debris piece is equivalent to around 0.2 kg (200 grams) of TNT. To put that into context, a U.S. Navy lightweight Mk54 torpedo has a warhead weight of 44 kg (we'll assume it's TNT even though it isn't). That means the missile would have kinetic energy equal to 0.4% of the explosive energy of a Mk54 lightweight torpedo - not enough to even be noticed.
BrahMos Missile Debris
Now, what about a large, supersonic missile like the BrahMos (3000 kg, Mach 3)? Let’s check. Without all the wordiness, and repeating the above calculations for a piece of debris 1/10th of the original missile and a velocity at impact of ½ the original speed. That gives us,
mass = 0.1 * 3000 kg = 300 kg
velocity = 0.5 * Mach 3 = Mach 1.5 = 1140 mph = 510 m/s
so,
k.e. = 0.5 * 300 kg * (510 m/s)*(510 m/s)
k.e. = 39,015,000 (kg*m2)/s2 = 39,015,000 J
By comparison, a kg of TNT releases 4,184,000 J. Thus, the k.e. of the debris piece is equivalent to around 9 kg of TNT. To put that into context, a U.S. Navy lightweight Mk54 torpedo has a warhead weight of 44 kg (we'll assume it's TNT even though it isn't). That means the missile would have kinetic energy equal to 21% of the explosive energy of a Mk54 lightweight torpedo - not insignificant but nowhere near enough to be a threat to the target ship.
Mini-Summary
These calculations tell us that debris is simply not a threat to the defending ship, at least not as regards kinetic energy of the debris piece. Thus, the hysteria over debris from a CIWS engagement is just that: unfounded hysteria. Fortunately, our public school education has delivered us from the land of hysteria to the realm of science and informed discussion.
Larger Caliber
On a related note, one of the constant calls among naval commentators is for larger caliber CIWS weapons so as to enhance lethality. While the use of larger caliber rounds would increase lethality, it also decreases ammo inventory and firing rate. Anyone who has watched a CIWS live fire video cannot help but be struck by the startling inaccuracy (spread) of the rounds. The scatter is significant. What compensates for the scatter is the high rate of fire. Therefore, given how little it takes to destroy a warhead and alter the path of the main missile body, the gain in lethality does not justify the loss of ammo inventory and firing rate.
Below are screen captures taken from videos of a CIWS shooting at a small boat. Note the spread of the splashes. There was no information about the range or conditions of the exercise but the impression is that the range was very close and still the scatter was quite large.
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| Note the Scatter |
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| Again, Note the Scatter |
Still captures from video: https://www.youtube.com/watch?v=Zsf38NYzo5Q
It’s not that CIWS is any less accurate than any other weapon – it’s not! It’s just that hitting a moving target (even a relatively large target like a boat as opposed to the frontal aspect of a missile) from a moving platform is very difficult. There are literally dozens/hundreds of factors that affect accuracy and most of those factors are not measurable or controllable. Worse, those factors are dynamically interrelated meaning that the relationships between them changes as their magnitude changes. We do the best we can to write software to predict the aim point but our best software efforts are still very poor, contrary to so many people’s belief that a simple software calculation guarantees one shot, one kill type of accuracy.
If we can’t hit a giant (relative to a missile’s frontal aspect) boat, how can we consider going to larger caliber rounds with less inventory and slower rate of fire? This is also why 5” guns are simply not effective anti-air weapons despite any overblown manufacturer’s claims.
Summary
To sum up, the job of a close in weapon system is not to vaporize an attacking missile but to render it non-explosive and, to the extent possible, as physically degraded as possible. If the CIWS can vaporize the attacking missile, all the better but that is not the minimum requirement.
The myth of debris continuing on, striking the ship, and doing significant damage is a complete fallacy. Debris myth-holders also lose sight of the fact that, even if the worst were to happen, it is still far preferable to be hit by small, unpowered, slow, non-explosive, pieces of debris than an intact, functioning, explosive missile. This is symptomatic of today’s tendency to criticize as worthless any weapon that cannot do a guaranteed, 100% perfect job. This is why critics decry armor just because it can’t totally stop every weapon ever made, while ignoring the overwhelming benefits armor bestows by containing and mitigating the extent of damage. This kind of shortsightedness is crippling our ability to field highly useful and beneficial systems that are less than perfect. As we say - but actually do the opposite - perfect is the enemy of good enough. CIWS is plenty good enough.
So if the critics don't like CIWS or armor, what do they think should be done?
ReplyDeleteHarsh Language
DeleteRE: larger size for the CIWS shells.
ReplyDeleteDo we happen to know if there are any modern missiles that are tough enough that they could shrug off a direct hit from a 20 mm projectile without penetration or damage? That would be the only valid reason I can think of for going to larger shells.
You could argue that your assumption that hits on the anti-ship missile will cause it to break up is questionable if not flawed (unless Phalanx 20 mm projectile more effective than expect, need actual trials to confirm either way) why say that is actual battle experience.
ReplyDeleteIn 1944-1945 Navy found that the 20 mm Oerlikons and 40 mm Bofors shells were unable to stop Japanese Kamikaze a/c, the Kamikaze kinetic energy was so much larger that they shrugged off the effects of the small shell hits to still impact on ship. The Navy relied on their much more powerful ~55 lbs shells fired from the 5"/38 whilst developing the Mk 22 3"/50 with a VT fuzed shell which never made it into service before end of war in any numbers.
Would note the Kamikaze A6M Zero had approx same KE as the C-802, much heavier mass though much lower velocity so balanced out, think chance of Phalanx stopping a BrahMos very unlikely.
"You could argue that your assumption that hits on the anti-ship missile will cause it to break up is questionable"
DeleteThat's the myth assumption, not mine! However, I've not heard of any exercise example where a target was hit by CIWS and did not break up. Have you?
" Navy found that the 20 mm Oerlikons and 40 mm Bofors shells were unable to stop Japanese Kamikaze a/c"
You're failing to grasp the nature of an aircraft. It's mostly air! WWII aircraft were thin shells. A shell could, and often did, pass cleanly through without doing significant damage. Barring a lucky hit on the pilot or engine, a WWII aircraft could absorb many dozens of hits with not significant effect, not due to kinetic energy but due to the lack of vital components in the aircraft. In contrast, a missile is densely packed - almost solid - and any hit will be vital and damaging.
DeleteFor the Zero,
2796 kg
333 km/hr = 92 m/s
k.e. = 0.5 * m * v2
k.e. = 0.5 * 2796 kg * (92 m/s)*(92 m/s)
k.e. = 11,832,672 (kg*m2)/s2 = 11,832,672 J
The C-802 ke=33MJ. Thus, the Zero max ke is a third of the C-802.
Wikipedia quotes Zero never exceed speed 600 km/h, assuming Kamikaze pilots when in attack dive mode would be pushing near the limit, would ~550 km/h have been possible, if so calc becomes
Deletek.e (0.5*2796 kg) * (153 m/s* 153 m/s)
k.e 1,398 * 23,409 = 32,725,728, ~33 MJ, so near same as C-802 33 MJ
"A shell could, and often did, pass cleanly through without doing significant damage" maybe 50/50, have seen no authenticated analysis for actual figures, my impression that it was true in WWII, reason why the fighters progressively up gunned with the American Browning 0.5" and British and Germans 20mn cannon. We know the Kamikaze a/c was taking hits from the 20 mm and the much larger 40 mm shells but surviving with minimal breaking up due to its kinetic energy over the short distance before impacting on ships. A ship defended by Phalanx with effective range limited to ~ 1-1.5 km, BrahMos attacking at ~Mach 3, Phalanx may have ~ 25 sec to acquire target and shoot before impact with its 1,588 MJ (0.5*3,000) *(1029*1,029), as said think unlikely BrahMos even if hit by Phalanx in the last few seconds due its massive kinetic energy/speed would stop it impacting the ship even if it missile did break up.
As said need actual trials pitting the Phalanx against BrahMos to see if our different estimates near actuallity
PS Ryan Firebee
k.e. (0.5*934 kg) * (282 m/s*282 m/s)
k.e 467 * 79,524 = 37,137,708 - 37 MJ vs BrahMos 1,588 MJ
E&OE :)
You're attempting to equate a WWII 20mm Oerlikon with a Phalanx CIWS and they are very different weapons.
DeleteThe effective range for the WWII 20mm was 1000 yds or less with a rate of fire of 300 rds/min, and a muzzle velocity of 800-1000 ft/s, depending on model. In contrast, the CIWS effective range is 1600 yds (6000 max) with a rate of fire of 4500 rd/min, and a muzzle velocity of 3600 ft/s, depending on model.
So, the WWII 20 mm had a shorter effective engagement range, slower rate of fire, and slower muzzle velocity. In addition - and very importantly - the WWII 20 mm was optically guided so hits were single (one at a time). By comparison, a CIWS is 'double' radar guided and when hits occur, they occur in relatively large numbers as the bullet stream is guided onto the target by the radar. Thus, WWII aircraft would get hit by an occasional, single shell whereas a modern missile will get hit by a stream of shells. Combine this with the previously noted 'airiness' of the WWII aircraft versus the dense missile and it's easy to see that WWII aircraft were, indeed, a difficult target (not due to kinetic energy; you're actually referring to inertia and momentum) whereas a modern missile is actually an easier target to destroy if it's hit.
Another factor you're overlooking is the shells. As opposed to the WWII 20 mm steel shell, the CIWS round is an armor-piercing tungsten penetrator round.
DeleteThe smaller Oerlikon 20 mm was found to be ineffective against the Kamikaze, however by early '45 even the Bofors 40 mm was found inadequate which led to the 3"/50 and reliance on the 5"/38 as mentioned earlier.
DeleteBy '44 the Navy were well on the way to replace the 20 mm Oerlikons with the Bofors 40 mm with its Mk 22 fuze found to be 99.9% efficient in its ballistic acceptance tests. Of the 400+ destroyers built between '34 and '46 only four not fitted with the Bofors 40. In 1944 alone 6,644 singles, 3,650 twin and 750 quad mountings built for Navy.
Source Navweaps.com
Re the shells/projectiles many things to consider, weight of round - Phalanx 0.58 lbs vs Bofors 4.75 lbs (very noticeable how the larger dia increases the firepower as with 5" Mk 45 with its ~ 70 lbs shell whereas the Mk 71 8" ~240/260 lbs shells) rate of fire and as you say the Phalanx 0.22 lbs armor-piercing tungsten penetrator round vs the fuzed 2 lbs shell of the Bofors of WWII.
Here's a video of a Phalanx intercept of a Ryan Firebee target drone that goes on to hit the ship carrying the Phalanx.
ReplyDeletehttps://www.reddit.com/r/MilitaryGfys/comments/el0jwh/phalanx_ciws_successfully_intercepts_a_ryan/
https://external-preview.redd.it/bui8pRgLL5UegreQquZu9AbEJMUBpW1Xvgy3q_6czDI.gif?format=mp4&s=0603b83716a318ce6570bd4959344a251844bf60
Actually, very close frame by frame examination of the video leads me to doubt whether the debris hit the ship or just passed close (over?) it. At the end of the video, the camera pans back to the ship briefly and there is no evidence of damage or fire on the ship although, admittedly, the camera angle does not allow a clear view.
DeleteThe fact that the piece of debris that supposedly impacted the ship also winds up flying past the ship in unaltered form, as best I can tell, also suggests that it did not hit anything.
The fact that the piece of debris that supposedly hit the ship flies past with its trajectory unaltered still further suggests that it didn't impact the ship.
I also note that the intercept occurred at a very short range (100 yds?) which would be atypical for a CIWS engagement. It looks to be one of the old self-defense test ships so this may have been a case of testing to see how close an intercept could be done. Pure speculation on my part.
It looks to me like it bounced off something on top of the deckhouse and disintegrates.
DeleteThe first hits start around 8s and it impacts at around 15s. If the Firebee was traveling at 300mph, or 134m/s, it would have flown 940m in 7s. It may've been flying faster initially and obviously slowed down once it was hit and started to tumble.
The max effective range of Phalanx is around 1,500m, so this may be a fairly typical engagement.
No, you're misinterpreting what you're seeing. The first discernable flash of an intercept is at 9s. The main body impacts the water at 11s. The major debris piece cartwheels on and appears to be re-engaged by CIWS at 14s (a bit earlier, I'm sure, but it's out of frame) as evidenced by the large puff of smoke in front of the CIWS before the debris reaches the ship and begins to flame just before crossing the line of the ship. If it had impacted the ship, it would altered its trajectory. The flame is not from impact but from the re-engagement.
DeleteAdmittedly, the camera angle and clarity do not lend themselves to absolute certainty but I'm reasonably confident in the sequence I've described.
The speed of the debris piece, having previously impacted the water, would be very slow compared to the original missile speed, whatever that was, so your distance calc is likely significantly off. The visual guesstimate of distance is on the order of 100 yds.
Regardless of the exact distance or sequence of events, this clearly demonstrates the desirability of having a CIWS versus not which is what so many commentators call for.
Here's a better video, with multiple camera angles. The fuselage definitely hits the ship.
Deletehttps://www.youtube.com/watch?v=KhTGIxbPwNY
In the first clip, at real time, the first discernable hits occur at 1:01.6. The fuselage begins to bank at around 1:04.
Assume it was flying at around 500kts to start (simulating an anti-ship missile), or around 250m/s. 2.4 seconds flying at 250m/s is ~600m by itself.
Then the drone continues to roll and disintegrate, and the main body impacts the ship at 1:08.0, 6.4 seconds after the initial detectable hits. It was undoubtedly flying slower through this part, but it's hard to know how much slower. Probably still in the 2-300kt range. For the sake of argument, assume 200kts, 100m/s, for 4 seconds, or another 400m.
Total estimated distance from first obvious hits is ~1000m +/- a couple hundred meters.
There's no way it was only 100yds. 6.4 seconds to cover 100 yds means it was flying at an average speed of 27 kts.
Sorry, no, nothing appears to hit the ship. The debris piece does not alter trajectory as it would if it hit the ship, the ship has no apparent damage or fire as it would if that flaming debris had hit, and the CIWS clearly re-engaged and set the piece on fire.
DeleteIf you wish to see something that's not there, feel free.
https://youtu.be/KhTGIxbPwNY?t=137
DeleteThis moment appears to be right after the fuselage hit something on top of the ship, which probably ignited the remaining fuel in the drone causing the fireball. Of course it's possible that it missed the ship and the drone just happened to break up and ignite at the same moment, but it was intact right before this (see here https://youtu.be/KhTGIxbPwNY?t=447).
Regardless, the engagement appears to have started somewhere around ~1,000m and ended with the drone fuselage either hitting the ship or the fireball from fuel reaching the top of the ship. Either way, a major portion of the drone reached uncomfortably close to the ship.
As I've stated, the CIWS re-engages (visible at 1:06 in this video) and the debris begins to ignite PRIOR to passing over the ship. That part's pretty clear.
DeleteNone of the views in any of the videos definitively show whether the debris impacts the ship although I'm pretty confident it didn't for the reasons I've listed.
Regardless, it does not alter the post premise in any way so it's irrelevant other than as a matter of curiosity.
Clearly if there is any impact with the incoming missile at all, there will be some alteration of path for any debris. And the speed of any debris should slow because of the combined effects of no power plus atmospheric friction. If the impact occurs too close to the ship, then there may be enough momentum left to cause contact with the ship. Obviously, the further away the impact, the better.
ReplyDeleteWorst possible case, you have the choice of having an intact missile with explosive warhead impacting the ship, or some remnant debris from that missile impacting the ship, likely not including the explosive warhead or the engine and fuel. Not a hard choice.
You just have to make sure one or more of your bullets impact the missile, preferably before it gets to close. Which brings to mind the old fleet acronym for CIWS, "Chr***, it won't shoot."
"preferably before it gets to close."
DeleteWhich is why we have (or should have) a layered defense with ESSM, SeaRAM, and CIWS. The fact that our Burkes have no SeaRAM and only one CIWS is stupid beyond belief.
"Which is why we have (or should have) a layered defense with ESSM, SeaRAM, and CIWS. The fact that our Burkes have no SeaRAM and only one CIWS is stupid beyond belief."
DeleteAbsolutely.
Seems to me the argument than is more CIWS. Some top side armor with the aim of dealing the potential of some shrapnel. And stop minimizing crew size so has to have sufficient fire control and damage control on hand to deal with a spray of burning fuel or surface damage promptly.
ReplyDeleteThe first two Kirovs had 8x CIWS (AK-630, 30 mm). Contrast that with our Burkes which have 1x CIWS.
DeleteAdd also when deployed as a single unit the CIWS almost always has a blind spot. Also the desire to not have redundancy (for any and all reasons) is appalling.
DeleteEdit: To add. I mean say with a individual infantry soldier you can I think start easily to overload somebody to much armor, weapons, kit, batteries tech etc. But a ship either as a kill or mission kill is a lot crew you spend a lot of time to train. I don't really see the navy desire of minimizing redundant systems and crew.
DeleteTesting is the way to answer whether the incoming missile is turned into ballistic shrapnel or not. I would note that grenade shrapnel (not necessarily the blast) is VERY effective against soft targets (Humans!). If our Radar faces are as soft as human beings then the debris (shrapnel) could be just as effective. Again REALISTIC testing is required. I don't know if a Spy radar face has been subjected to shrapnel testing. Probably not given the Navy's avoidance of uncomfortable facts. Test, Test, Test, analysis is only as good as the inputs. Test rather than speculate, pontificate, and obfuscate (Navy path to advancement)
ReplyDeleteYou may be mis-visualizing shrapnel. A grenade is designed to break into shrapnel. A missile is not. A missile that is hit by CIWS shells will break into pieces, not an intentional pattern of shrapnel. Now, if you're referring to those pieces as 'shrapnel', that's fine but then you need to recognize that, unlike an intentional shrapnel-producing device, the pieces from a broken up missile are relatively very few in number (a handful of 'chunks') and are slowing VERY RAPIDLY, unlike a grenade exploding in the immediate vicinity of a target.
DeleteSo, will pieces damage a radar array if they hit? Sure! But, not to any great extent physically (don't know about the electronics damage) and the likelihood of such impact is small, as demonstrated in the post. Any piece that hits an array (or any other object) will, AT MOST, make a dent/hole the same size as the piece since there is no explosive effect. So, small pieces produce small dents/holes (again, unknown electronics effect). As the post demonstrated, there won't be any significant kinetic energy damage.
You are correct about testing. There are so many things the Navy needs to be realistically testing ... but aren't.
Testing matters!! With so many unknowns, and so many ships coming up for decommissioning, it really seems like a real, true test of Aegis, the missiles, and the CRAM/CIWS could be possible. Im sure the Navy would like to immediately scrap, rather than mothball the Ticos so they cant return. And even IF they're mothballed, Id gladly sacrifice (the absolutely oldest one) one in a series of tests to actually see how she performs!!
Delete@Jjabatie. Agree but there's no WAY USN would use an old Tico for testing purposes!!! We all know USN will never allow it.
DeleteIf navies believe debris is a threat (even after CIWS), then they should believe in armoring ships to a significant degree.
ReplyDeleteFantastic number-crunching article!
"then they should believe in armoring ships to a significant degree."
DeleteAstutely correct!!! They should also believe in [many] multiple CIWS per ship so that several guns can engage a target and debris, leaving nothing to get to the ship. The single CIWS on a Burke is a joke. We're going to lose a lot of Burkes in combat due to that.
"While the use of larger caliber rounds would increase lethality, it also decreases ammo inventory and firing rate."
ReplyDeleteNot necessarily. China's type 1130 use 30mm ammunitions, it fires far faster than Phalanx CIWS.
As do the 30mm Goalkeeper and Soviet/Russian systems. The difference is that they are deck-penetrating with dedicated magazines instead of being a bolt-on system like the 20mm CIWS.
DeleteI personally see the need for a mix and I think there were lessons learned in WWII repelling kamikaze attacks that could be applied. The larger systems (including short-range missiles) being the heavy hitters like the USA 5"/38s were and the deck-mount systems filling the role that 20mm and 40mm bofors were used for covering gaps in the 5" coverage and engaging the close in targets.
Conceptually I really like the Russian Kashtan and Pantsir systems with a huge volume of fire and on-mount short range missiles. Combining them with proximity fused or programmable airburst ammunition is the next logical step.
This is all fine and good a 1,000 meters out. But, what happens when the engagement is closer, at say 100 meters?
DeleteI suggest you Google the web and find out type 1130 as there are plenty information online.
DeleteRussian CIWS use two Kashtan to achieve high firing speed but vibration from one affect accuracy of the other. Yes, CIWS still need certain accuracy.
China's type 1130 (11x30mm Cartiling style) use two ammunition chains, each 1080 rounds. Giving its speed of 11,000/min, each chain works only few seconds as final defense. Of course, its ammunition chain must place in certain way otherwise could not support this firing speed.
Unlike US adopts "either CIWS or SeaRam", large Chinese ships have both type 1130 and HHQ-17.
"what happens when the engagement is closer, at say 100 meters?"
DeleteWhat happens when the engagement is at 1 meter?
Your turn.
Maybe your "theoretical consideration of the debris strike scenario suggests that it is unlikely" isn't all that unlikely.
DeleteIf you think the post premise is not correct then refute it with facts and logic instead of just offering a vague, unsupported feeling that you think it's 'unlikely'. You can see how worthless such a comment is, right? You really need to improve the quality of your comments, overall. Read the Comment Policy page. You're not meeting the standards.
DeleteThis blog is NOT going to degenerate into a child's level of back and forth 'you're wrong', 'no, you're wrong'. The blog insists on data, logic, and intelligent discussion.
You can see why I'm going to start deleting your comments if they don't improve, right?
I think the main issue here is that the 20mm shells are not powerful enough to reliably achieve missile fragmentation and disintegration. I agree that it's not realistic to expect a phalanx to 'vaporize' a missile either.
ReplyDeleteAlso, while a kill can of course be achieved from a warhead detonation, as in your example, this is hardly a guarantee. Another possibility is that a kill is realized simply by damaging the missile body sufficiently so as to render it un-aerodynamic enough that it shortly thereafter collides into the sea. You don't have to break up the missile body into large pieces to achieve that effect. We saw this in the firebee example, where the drone remains largely intact immediately after the first hit (until it lost aerodynamic stability and broke itself up).
With large supersonic missiles, like the brahmos, the phalanx might only have a small 2-3 second window from the start of the engagement envelope to a ship hit. In fact, assuming a 0.8 mile effective range, that engagement envelope might be as little as ~1.2 seconds!
Unless a warhead detonation or missile fragmentation is achieved (the latter being more difficult with larger missiles like the Brahmos), that less than 3 second window (bearing in mind that the start of the engagement window is not always co-temporal with the actual hit on target) might not be enough for the missile body to fall into the sea.
In the firebee example, it took about 2-2.5 seconds from impact for the drone to sufficiently "tip over" enough such that it started experiencing significant deceleration forces and breakup. And many more seconds for the now slow moving debris pieces to collide with the sea.
The point is that a mostly intact supersonic missile body slamming into the superstructure shortly after a phalanx impact seems a credible myth. Certainly, it should not be dismissed as a "myth". I definitely agree that the risk is far less certain with subsonic missiles though.
To sum up: Yes your specific scenario is probably unrealistic, but that doesn't mean that there's isn't validity to the general concept of the CIWS debris risk.
"The point is that a mostly intact supersonic missile body slamming into the superstructure shortly after a phalanx impact seems a credible myth"
DeleteSeems a credible risk I meant to say!
Last correction to pre-empt what I am sure are to be misunderstandings:
ReplyDelete"I think the main issue here is that the 20mm shells are not powerful enough to reliably achieve missile fragmentation and disintegration"
Hopefully it was clear from the rest of my post that I meant DIRECT substantial missile fragmentation, as opposed to the missile body itself disintegrating from aerodynamic forces later on. Of course, the phalanx should be able to reliably achieve missile kills given hits on target.
CIWS salesman: I'm not saying we won't get our hair a little mussed"
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testing
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