Issues on Intercepting Hypersonic Missile.

Scratch said:

??? The Harpoon is produced by a US manufacturer and used by the USN, why do you even bother to doubt those missiles can't be perfectly mimiced by drones. They can just use their own missiles for those tests.
I guess that may also be true for Exocets.

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Gee, things like different weight, size, flight performance, radar signature, heat signature, radars.... the list goes on and on.

You can't just flip a knob on a Vandal or a Coyote and turn it into something with a totally different size and weight. Sea-skimmers like Harpoons are much smaller than ramjet supersonics.

In any case, the facts are VERY CLEAR. It's known that in testing of ESSM, standard practice is to launch 2 missiles for each incoming Vandal, programmed to fly a low altitude, weaving maneuver in the terminal phase (probably the most difficult maneuver to intercept).

But a Vandal is a very backward, very obsolete drone or missile. The Coyote is much newer and challenging for testing. Therefore, the standard practice against Coyotes flying a low altitude, weaving maneuver must be 3 missiles or more.

Finally, even the Coyote is less capable than a Harpoon -- especially since the Harpoon will be detected much later... as in when it turns on its active guidance. So against a Harpoon flying a low altitude, weaving maneuver, the standard practice must be four missiles or more!

Even then, it's not clear if the above "standard practice" is to get a 95% probability of kill or higher. I think in a wartime footing, if the defending ships expect multiple incoming antiship missiles, it would not settle for a 95% probability rate. It would need 99% or above.

Then that would mean you need to add an additional missile to the above: 3 missiles against Vandal "class", 4 missiles against Coyote "class" and 5 missiles against Harpoon "class."

I didn't think you really answered the issue. If you want something to mimic a Harpoon, why do you need a Coyote or Vandal if you can use Harpoons directly. Take out the explosives and put some ballast and you get a potential target drone. And there are also subsonic drones like the BQM-74A/B/C/D/E/F Chukar.

Vandal is a very interesting system. It's based on the RIM-8 Talos, which in the fifties was the first ramjet SAM, though later variants can be modified to attack land targets. Its way ahead of its time considering we're back looking at ramjet missiles again, for AAMs initially at least. But its overly large size is probably what ended its career as a SAM.

crobato said:

I didn't think you really answered the issue. If you want something to mimic a Harpoon, why do you need a Coyote or Vandal if you can use Harpoons directly. Take out the explosives and put some ballast and you get a potential target drone. And there are also subsonic drones like the BQM-74A/B/C/D/E/F Chukar.

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That's actually not exactly the issue. They are saying that because publicly disclosed testing use only two-missile salvos, in a live conflict a two-missile salvo will be enough.

This is incorrect because the test that are publicly disclosed are not as challenging as they could be. I point out that a more challenging scenario would be using Harpoons instead of Vandals or Coyotes. I point that a Vandal, flying a terminal weaving maneuver, is not as difficult to intercept as a Coyote flying a terminal weaving maneuver. And a Coyote, flying a terminal weaving maneuver, is not as difficult to intercept as a late block Harpoon flying a terminal weaving maneuver.

Publicly disclosed tests show two-missile salvos used against Vandals. My point is that a three+ missile salvo would be used against Coyote and four+ missile salvo would be used against a late block Harpoon.

How come you keep on insisting the testing is only done against Coyotes and Vandals? Do you know what a Chukar is?

The real challenging tests are not public information. Obviously, the USN will take the results of its testing and calibrate the number of missiles (Standards or ESSM) it would fire in one salvo against this type of missile.

The tests that are made public are not challenging. This would be because the targets they use are obsolete things like Vandals. Or it would be because the targets are programmed to fly an easily interceptible route like a straight line without any maneuvers.

See these series of tests in this video. Notice that they don't make public how the system would do against a Harpoon target flying a sea-skimming, maneuvering profile.



In fact, if an early 60's missile like a Vandal, flying a low altitude weaving profile, would require a 2 missile salvo to have a high probability of kill, how many would be required for a Coyote? How many for a Harpoon?

All this is not public information, but we can properly infer the result.

By the way, crobato, how many interceptor missiles do you think would be necessary against a Harpoon to have a 99% probability of kill?

Vandals I think were exausted in 2005 and are no longer used, Coyotes only finished test phase in 2005 and therefore are realy new missiles I would say. Even though flight avonics and front end section are apparently taken from an AQM-37D drone.
And from what I got out of the vid, they used only one ESSM on the Harpoon and the high diving Vandal I think. The BQM-74, wich I believe represents a modern subsonic seaskimmer was also shot down by one or two ESSMs.
How can you say that it those test, only the most simple flight profiles were programmed into the missile, did you do it?

Did you notice from the video how many missiles it took to intercept a Harpoon target flying a sea-skimming weaving maneuver? That's the most challenging test they could have set up.

A Chukar is 70's vintage tech. A Vandal is early 60's vintage tech. Neither is even remotely close to mimicking a modern anti-ship missile. Just because two-missile salvo is fired when these drones are programmed to fly a terminal weave profile doesn't mean two missiles will be enough for a late block Harpoon.

Yet there are no publicly disclosed tests against a Harpoon target, at least not a Harpoon that approaches in a sea-skimming, maneuvering profile.

The current Chukar version with new software, among other things, was introduced in '92. Just Because it comes in an older airframe doesn't make it obsolete as a system.
I think against a rather small, sea-skimming target, the most difficult part is to detect and track it. If you don't see it or lose track in the waves, it doesn't matter if you launch 1 or 5 missiles. But when you can maintain a solid lock, a late gen SAM has a very good chance of hitting it. Said AShM just can't make sudden jumps in space-time to dodge a SAM.

Chukar E resembles like a cross between a Tomahawk and a Harpoon. This and plus the new software tell me how obsolete it is? Its really the software that counts. The so called "modern" anti-ship missiles are still based on airframe designs that originated in the seventies and that includes the YJ-83 which resembles a cross between a Harpoon and an Exocet (both designed in the seventies) and YJ-62 (similar to a Tomahawk).

crobato said:

Chukar E resembles like a cross between a Tomahawk and a Harpoon. This and plus the new software tell me how obsolete it is? Its really the software that counts. The so called "modern" anti-ship missiles are still based on airframe designs that originated in the seventies and that includes the YJ-83 which resembles a cross between a Harpoon and an Exocet (both designed in the seventies) and YJ-62 (similar to a Tomahawk).

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Even the latest versions of the Chukar cannot skim the water as low as Harpoon. Its less powerful engine means it loses energy much more easily during maneuvers. It's larger in size. It looks more bloated and less capable of performing terminal maneuvers than Harpoon.

On the whole, the impression of Chukar, even the latest versions is that it is intended to a generation below Harpoon. The difference between the two is at least as great as between Vandal and Coyote. If standard testing is two-missile salvo against a Chukar, I think a Harpoon flying a sea-skimming, weaving profile would merit 4+.