Issues on Intercepting Hypersonic Missile.

man overbored said:

Ok, one point at a time.

"The incoming anti-ship missile has no means to sense RAM. RAM uses passive guidance, IR and RF. It does not emit.

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why not? the body of the seaRAM is metal , it will reflect radar wave right?
Also, it's exhaust is also be detected by IR sensor. Unless you telling me SeaRAM is constructed like a B-2.

Target missile is active homing therefore no datalink, EW is no use.

As for CIWS, the question I like ask is do you need prediction?
If you asnwer No it will become a different ballgame. Yes or No is sufficient for this question.

King_Comm said:

... if the missile is large and armoured, the rounds fired in that time may not be sufficient to bring it down. RAM is slightly better, it has a range of 6km, so it has 3 seconds to shoot at the target.

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Never, ever, will a missile be armoured. Weight is an important issue, and armor is just not feasable therefore. A missile going M5+ at such low altitudes needs a LOT of fuel to travel any meaningfull distance, therefore it will already be big and heavy anyway. Unless a revolutionary new propulsion is discovered. That weight and extreme speed will also affect the missiles maneuverability and restrict evassive action.
If such a missile gets that close however, there will of course be a lot of debris hitting the ship with high momentum, even if it's hit by the CIWS bullets.

lilzz said:

why not? the body of the seaRAM is metal , it will reflect radar wave right?
Also, it's exhaust is also be detected by IR sensor. Unless you telling me SeaRAM is constructed like a B-2.

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If an AShM detects it's being engaged, and if that'll even work, what do you exspect it to do? Evade the incoming RAM only seconds before the AShM hits the target? If it does, it pretty sure won't regain contact with the ship and miss. That's a win for the RAM. Furthermore, there's not much space on a missile for a powerfull EW suite, so jamming the RAM with a AShM is also somewhat theoretical.

Target missile is active homing therefore no datalink, EW is no use.

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Of course EW is of use. EW is not restricted to jamming data links, but also (active) radars, and a lot of other things. Your missile might then perhaps answer with home on jam. But that doesn't guarantee success either.

Scratch said:

If an AShM detects it's being engaged, and if that'll even work, what do you exspect it to do? Evade the incoming RAM only seconds before the AShM hits the target? If it does, it pretty sure won't regain contact with the ship and miss.

Of course EW is of use. EW is not restricted to jamming data links, but also (active) radars, and a lot of other things. Your missile might then perhaps answer with home on jam. But that doesn't guarantee success either.

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what it will do when it senses SeaRAm is coming close. like varying its speed, so make it hard for you to predict its next point. or accelerate and make a dash in sudden move to pass your predicted interception point which is based on previous speed.

how do you jam a LPI radar which featured on board?

Adjust to varying target speed is not a difficult task for an anti air missile, it constantly and nearly simultaneously calculates the intercept point and maneouvers accordingly.

A ship has enough space to carry a sophisticated ESM and EW suit. I'm absolutely no expert in that. But LPI does not mean it's impossbile to detect or jam it. A hypersonic AShM is way into the future, and over time there will also be new techniques available.

With that speed, I'm wondering if the missile won't create a plasma cone around the nose anyway. That would then interfere with the radar I guess.

Scratch said:

Adjust to varying target speed is not a difficult task for an anti air missile, it constantly and nearly simultaneously calculates the intercept point and maneouvers accordingly.

With that speed, I'm wondering if the missile won't create a plasma cone around the nose anyway. That would then interfere with the radar I guess.

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Yes, the target missile and the interceptor missile both can adjust the speed.
but remember, the target missile is the initiator, the interceptor is the reactor,
the target missile wait till the interceptor very close and then suddenly acclerate, so it's too late for interceptor to adjust, its' already overshoot and past the interception point. It's momentum will carry it far .. it's too late, the seaRAM can't recover once it past the point. It cannot try to turn around and try to chase down the hypersonic missile.

therefore, at close distance where the reaction time is small, the initiator has all the advantage espeically the "dumb" seaRAM where the SPY 1 radar has to feedback the information back to interceptor missile and then activate its speedchange and direction.

Well even if you make SeaRAM "smart" by having active homing, and has onboard cumpter to recalculate and predict a new interception point, it still reacting, it might not have enough reaction time if "sudden move" excuted by the target missile at close distance.

as for plasma, the radar doesn't have to be in the tip. It can be install underneath the missile's mid-section belly.

No, once fired missiles have no way to adjust speed. Solid fuel rocket motors cannot be throttled, and besides their burn time is measured in seconds. The fuel is right against the skin of the missile so the missile body cannot tolerate much more heat than this. You guys really have never been anywhere close to guided missiles.
The small gas turbines of something like a MM-40 Exocet, Harpoon or TASM have simple solenoid operated fuel controls that are either on or off. They make full power or no power, that's it. Once either a solid fuel rocket or turbojet cruise missile is fired it's speed is set.
One point is correct, the high mach cruise missiles take so much room to maneuver and burn fuel so fast that reattack is impossible. Something like Harpoon or SLAM-ER, if spoofed off it's intended target by countermeasures has multiple seekers ( Block 3 Harpoon and all versions of SLAM-ER ) that enables them to come around and reattack. This is a specific design feature.
In the notional RAM vs Sunburn engagement, there is no way for the Sunburn to sense a RAM. Sunburn, like other active homing missiles, locks on to a target and then performs a pre-programed set of evasive maneuvers before striking the target. There is no provision for evading defensive missiles, and as pointed out, any evasive maneuver would be a win for the ship as it would put the missile off of it's target.
EW is useless against RAM, it homes on RF emissions ( ever hear of "home on jam" ) and has a very advanced IR seeker. Even a passive homing missile like C-802 with it's anti-radiation homing seeker is successfully engaged by RAM.
We practice defending against target simulators like the mach 2.8 ( and that is mach 2.8 at ten meters altitude, significantly faster and lower than 3M80 will manage ). These are high fidelity simulations of major threat systems. In actual practive RAM nails over 95% of these fast movers on the first engagement.
You folks also keep ignoring that these are head on engagements. The missile is heading directly at the RAM of CIWS. There isn't as much lateral movement as you imagine in these engagements. It is not that complicated a fire control solution to bring a stream of tungsten into a collision course with a missile that is coming straight at the gun. RAM has plenty of time for the engagement and will get better with rocket motor improvements. RAM Block 2 is quite a missile with double the propellant and much greater maneuverability and it fits in the original launcher.

lilzz said:

I see, it's also a prediction. Man overbored make it sound as if automatic with certainty. therfore I was confused for a moment.

like I say, if the missile vary its speed when illuminated, then make it harder to predict its next point. so the point the bullets anticipate could be wrong.

also, within the CIWS range, the target missile evasion action can be throttle its speed or slow down a bit and let the bullets fly by ahead. It's onboard radar can sense bullets are coming.

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Even if the throttles are fixed, its simple for a missile to vary its speed. That's through altitude changes. If you go high, it slows down, if you go down, it speed ups. Flipping up and down might be part of its evasive routine, and so if jinking side to side, which also causes some slowdown.

AshM's radar isn't going to sense incoming bullets, which have too small an RCS. Needs high frequency (X band at least) too much power and scan rate and AshM seeker radar isn't meant for that.

I will say again, based on working with actual military rockets, that you cannot alter the speed of an incoming missile. Missile flight controls are very simple. Complexity adds weight and reduces performance. You are perfectly free to delude yourself otherwise however Missiles at very low altitudes will have a lower speed on the same thrust than the same missile at high altitude, something most often ignored when people like to quote the supposed high top speeds of certain missiles. Low fliers loose a lot of their speed.

crobato said:

AshM's radar isn't going to sense incoming bullets, which have too small an RCS. Needs high frequency (X band at least) too much power and scan rate and AshM seeker radar isn't meant for that.

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what about IR seeker? can it sense the heat from the bullets?

man overbored said:

I will say again, based on working with actual military rockets, that you cannot alter the speed of an incoming missile. Missile flight controls are very simple..

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In order to achieve Mach 5 or Mach 6, it needs more than common simple rocket type. Maybe a Scramjet engine. Changing direction or maneveur is hard for such high speed, but accelerate or deccelerate should be fairly straightforward.

It believe the sunburn can accelerate duing terminal phase, but probably lacks the sensors for incoming interceptors like I described.