Issues on Intercepting Hypersonic Missile.

IronsightSniper said:

Well, as I said in one of my posts before, the Vandal shot down (at least by Raytheon) was indeed a Mach 2.5 missile, however, it was diving and not sea skimming. As for the Coyote, I honestly don't have enough information on them to actually print a picture, but it's not as if it was doing S maneuvers :3

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Ah, and we also had real Russian made Kh-31's to shoot, and they were nowhere near as fast or long ranged as advertised, 15 nm max in sea skimming mode, which makes me roll my eyes at some of the exaggerated claims for other Russian or Russian derived systems. Kryptons at Point Mugu, whoda thunk?



I think you will find that Talos could greatly exceed M 2.5 in a climbing intercept when it was the Navy's primary long distance air defense missile.

Oh yes, we also forgot the M 4 AQM-37:



It can simulate fast high divers.

Interestingly the Rocketdyne LR64-NA-4 liquid-fueled rocket used by the AQM-37, which burned hydrazine and red fuming nitric acid were also made by Harley Davidson back in the days when AMF owned Harley Davidson and their York Assembly division was part of the Naval Ordinance Factory, York Pennsylvania. Yup, Harley was a defense contractor making bomb casings, rocket motors and years before that plant made 40 mm cannon under license to Bofors. But I digress.........

To be fair, the Kh-31 isn't exactly a top of the line attack weapon. Contrary to what you've said about it, what I've heard about the MA-31 in testing was that it actually beat several US systems and was as fast as it was advertised, even disregarding the extra weight given to it by it's additional telemetry systems.

Ah yes, from what I can tell about the Coyote, it's indeed a Mach 2.5 sea skimmer. However, the different between that and say a Klub is that the Klub of course can preform High-G maneuvers, travel about 2 meters lower, and go about half a mach faster.

As for that AQM-37, it can't simulate the Kh-15

Ambivalent said:

Here is how on illuminator can handle four intercepts simultaneously. Keep in mind AEGIS is data linking to these missiles as they fly out using a data link capability built into the AN/SPY-1 radar itself.
First, the four intercepts have to be in close physical proximity in azimuth and elevation, within the width of the SPG-99's narrow beam. In a mass attack that is possible. Second, each of the four missiles will be looking for reflections on different frequencies and different codes. The missile only needs illumination for 25% of the end game to get close enough for the proximity fuse to detect the target and for the warhead to take out the target. Close enough works for this. The target illumination radar can rapidly switch between up to four freqs each coded uniquely for each intercepting missile, such that each missile homes on the correct target and one illuminator can thus provide terminal illumination for more than one target at a time.
Also keep in mind that with AEGIS, the SM-2 is flying out on inertial nav to a waypoint in space fed to it from AEGIS, and updated in flight as necessary by the data link feature of AEGIS. It is only the final second or so of the flight that requires illumination of the target.
With SM-6, no target illumination will be necessary, leaving the SPG-99's free to support ESSM's at closer range to take care of the leakers.

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The chance of a Mk99 illuminator's narrow 1 degree beam simultaneously landing on 2 incoming targets is very difficult, to speak nothing of 3 or 4, especially during a multi-vector saturation attack. This would most likely happen with a fighter launching both of its antiship missiles at nearly the same time. Also the exact time required for terminal illumination of a target is classified, so I doubt anyone can say with any degree of certainty whether it is "one second" or two, or three, or whatever.

SM-6's won't spread throughout the fleet nearly as fast as you imply. Many ships have yet to even receive the Block IIIB upgrade. The Navy certainly won't be replacing the entirety of the active SM-2 inventory any time soon. Block upgrades are usually done during major overhauls/updates that happen every few years for a given ship. Upgrading all 70+ Aegis warships with SM-6's will happen over a period of many years, perhaps even a decade or more.

Scratch said:

Finally, I believe that people are overstretching the advantage that an end-game maneuvering missile has against a defender, by a large margin, sometimes.

Especially with the speeds involved, turn radii will become really big, and a big, heavy missile also can only pull so many Gs.

If I got my stuff right, the picture looks roughly as follows:
A missile traveling at 815m/s (almost M2.5) in a level turn (20Gs) has a turn radius of close to 3.400m and turns almost 14 degrees per second. In the end, however, it still has to fly towards a rather small point in space, the ship. So it's maneuver options are rather limited.

In the pic below from the 3sec to impact point to the 1sec point, with the target traveling at 30kts against the missile turn, the angular difference from a gun on the ship between the two points is 12°. That means the CIWS mount has to turn at 6°/s to stay on target.

Taking a 530m/s (M1.6) missile at 20G, the radius shrinks to 1400+m and the missile turns a good 21°/s. From the 4sec to the 1sec to impact point the angle changes by 49° with the same assumptions as above. For the gun that means moving 16,5°/s.
Up & down truns will change the radii a bit, and all maneuvers will change speed (=slow down), wich in turn changes radii again.
But the # sound absolutely possibly. So (gun based) CIWSs do have their legitimacy to intercept leakers in the last moment.

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Interesting calculations.

However, a ship is not a point target. The majority is between 100m to 200m in length, while a CVN is more than 300m in length. Thus, a manoeuvring missile actually have some margin for error and yet can still hit its target.

The point of a missile manoevring in its terminal phase is to complicate the firing solution for CIWS. Its effectiveness has not been borne out in real combat, but it certainly beats a straight flyer.

As for the point about CIWS being able to engage multiple incoming missiles if they are coming in several seconds apart, I'd say that depends on how much ammo it carries in its magazine (not the ready use locker). If I'm not mistaken, the magazine contains enough rounds for ~30s worth of ammo for the CIWS firing at its max RPM (i.e., ~3,000 rounds). That's not a lot of ammo against multiple incoming missile.

I agree with your points here, intercept is by no means a foregone conclusion. My primary intent initially was to reject a statement that gun CIWS will outright fail against supersonic, maneuvering missiles. I just believe they have a realistic chance.
From a few youtube vids it seems a Phalanx fires bursts of between 2 and 4 seconds length. So maybe something between five to ten intercept attempts will be possible. Not much, but maybe enough for what could realisticly be fought off anyway by two CIWS on a ship.

Well, I must admit, I was spewing some propaganda there with some surefire words such as "absolutely fail" and the such.

But realistically, with the threat environment posed by Sunburns to Sizzlers, I'd much rather have the ship to which I hold residence to, to be carrying RIM-116s or Kashtans, rather than carrying a Phalanx or a Goalkeeper.

IronsightSniper said:

To be fair, the Kh-31 isn't exactly a top of the line attack weapon. Contrary to what you've said about it, what I've heard about the MA-31 in testing was that it actually beat several US systems and was as fast as it was advertised, even disregarding the extra weight given to it by it's additional telemetry systems.

Ah yes, from what I can tell about the Coyote, it's indeed a Mach 2.5 sea skimmer. However, the different between that and say a Klub is that the Klub of course can preform High-G maneuvers, travel about 2 meters lower, and go about half a mach faster.

As for that AQM-37, it can't simulate the Kh-15

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My old boss serviced MA-31's and loaded them on QF-4's and F/A-18's for training shots off California and was also involved in the sessions between the target operators, Boeing and their Russian counterparts when the Navy brought up the many shortcomings of MA-31 and Boeing engineers offered their fixes to the target.
As a sea skimmer, it could not break M 1.5 and at that speed had a max range of 15 nm. It's advertised range could only be achieved with a high altitude launch and a dive. The Navy needed a much longer ranged sea skimming target to achieve the presentation they were looking for. It also could not get low enough for the Navy due to shortcomings in the automatic flight control system.
A general shortcoming of all supersonic missiles is the inability to get down as low as their subsonic counterparts. The two meter altitude you claim for 3M54E is due to it's subsonic cruise. 3M80 and Kh-31/MA-31 need about 15 meters of altitude. Why? The computers and gyros necessary to stay ahead of the missile at such low altitudes must be extremely fast, and speed costs money for these items. Likewise, to control the missile at those speeds, the flight control surfaces themselves must be extraordinarily strong, and the flight control actuators very fast and powerful. Again, such controls are very expensive compared to those on subsonic cruise missiles. Last, the supersonic missiles have no reattack capability as the subsonic missiles do. Don't forget the USN has tested supersonic cruise missile prototypes as far back as the late 1960's with ALVRJ, SLAT and others and so far has not found them to be superior to TASM or Harpoon.
All of these necessary qualities, along with the cost of a solid fuel ramjets, tend to make supersonic sea skimmers three to four times as costly as their subsonic counterparts, making them too expensive to procure in tactically relevant quantities.
By the way, before 3M54E has it's separation event, it is no more or less difficult to acquire and shoot down than any other subsonic sea skimmer. It has to get well inside a CSG's defensive ring to come within the range of that supersonic kill vehicle.

ZTZ99 said:

The chance of a Mk99 illuminator's narrow 1 degree beam simultaneously landing on 2 incoming targets is very difficult, to speak nothing of 3 or 4, especially during a multi-vector saturation attack. This would most likely happen with a fighter launching both of its antiship missiles at nearly the same time. Also the exact time required for terminal illumination of a target is classified, so I doubt anyone can say with any degree of certainty whether it is "one second" or two, or three, or whatever.

SM-6's won't spread throughout the fleet nearly as fast as you imply. Many ships have yet to even receive the Block IIIB upgrade. The Navy certainly won't be replacing the entirety of the active SM-2 inventory any time soon. Block upgrades are usually done during major overhauls/updates that happen every few years for a given ship. Upgrading all 70+ Aegis warships with SM-6's will happen over a period of many years, perhaps even a decade or more.

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For grins if you don't believe me, you can pull up the 2011 Navy budget exhibits at the Navy Comptroller website and look at the P3, P5 and P40 Budget Exhibits for Missiles. You will find that SM-6 is in full rate production, some are already in service, and there is funding to convert the SM-2 inventory to SM-6. SM-6 is being rushed to service and will replace SM-2 entirely.

IronsightSniper said:

Well, as I said in one of my posts before, the Vandal shot down (at least by Raytheon) was indeed a Mach 2.5 missile, however, it was diving and not sea skimming. As for the Coyote, I honestly don't have enough information on them to actually print a picture, but it's not as if it was doing S maneuvers :3

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There have been hundreds of Vandals shot down over the many years of it's service. Both SM-2 and RAM have had good success against them and against Coyote.

Scratch said:

I agree with your points here, intercept is by no means a foregone conclusion. My primary intent initially was to reject a statement that gun CIWS will outright fail against supersonic, maneuvering missiles. I just believe they have a realistic chance.
From a few youtube vids it seems a Phalanx fires bursts of between 2 and 4 seconds length. So maybe something between five to ten intercept attempts will be possible. Not much, but maybe enough for what could realisticly be fought off anyway by two CIWS on a ship.

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You keep CIWS because the high cost of supersonic missiles guarantees most of the ordinance a ship will face including bombs and cruise missiles will be subsonic. Every navy you might face off against won't have such expensive missiles as 3M54E or 3M80 but subsonic sea skimmers are ubiquitous.
Your fire control system will evaluate the targets and prioritize weapons to engage them accordingly. SM-6 and RAM for the fast movers and CIWS can take care of the subsonic targets.
In Operation Praying Mantis the Navy chose to shoot less costly Standard MR's in the anti-surface mode at the Iranians rather than use Harpoon simply because the Iranians had nothing that outranged Standard and a 'Poon cost about twice as much as a Standard back then.