Issues on Intercepting Hypersonic Missile.

Finishing thoughts on this missile design.

I would design the shape of missile with reflection stealth feature shape, like I talked on the design of low cost stealth fighter.

I would put a subsonic booster stage which enable the missile range of 450km to 500 km range. During booster stage it's travling at subsonic. The missile stealth faceting feature would allow it go undetected like the F-22.

At beginning of interceptor range, booster off, the missile turn its engine and begin to go mach 2. Interceptor come in close and target aware of that, make an acceleration to mach3, zoom past the interception point.

at 20km, CIWS turns on and firing the bullets, target's IR sensor aware of bullets coming in and make another dash from mach3 to mach4 bypass the bullets and CIWS probably got one shot at that and missed.

Kaboom, the missile hit the ship.

several points regarding RAM

lilzz said:

... 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.

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I think the missile has a proximity fuse(?), so if it comes very close as you say, it might already detonate and release a lot of shrapnel impacting the AShM with high speeds.
Furthermore, your missile can't just "suddenly accelerate" from M3-M4. ManOverboard already stated the on/off part of missiles. Even if you could produce such a complex system in a missile (and high complexity isn't alway good) to accelerate that fast, you'd need an enormous amount of reserve energy.
I don't think a ramjet, or any airbreating engine could react that fast. That means additional rocket boosters, wich are again only dead weight before firing and also increase size.

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.

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Also the RAM isn't dumb at all, it is smart. It doesn't need the SPY, or any other foreign sensor at all once fired.
It's passive RF seeker senses the radar output of the AShM, and it's IR seeker sees the glowing skin of the missile body due to it's speed. That's all it needs, active radar homing is not necessary.
It makes all the calculations itself, and that takes rather milliseconds or even less. A M4 missiles "only" travels 1,3m in 1ms.

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

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If you put it there, that means you have something like a small pod, wich also "stands in the wind". The flowing air will heat up there as well and maybe create a plasma.

If you want a cruise booster for subsonic speeds, the best/most efficient way is a small turbojet/fan. So in your case you might want to launch a small UAV wich carries and launches one AShM once in range. That UAV could then be designed stealthy.
Then the missile might be launched with a rocket booster that seperates, and the missile might start it's ramjet.
Besides the point that I find it hardly beliveable an onboard IR sensor would reconize incoming bullets, I already said I also don't believe you can just go from M3-M4 in a second.
Furthermore, the missile is trying to hit a ship, and the CIWS is on that ship. ManOverboard already said that's rather a head on engagement. If the missile accelerates, it will only fly faster into the bullets coming towards it.

lilzz said:

Finishing thoughts on this missile design.

I would design the shape of missile with reflection stealth feature shape, like I talked on the design of low cost stealth fighter.

I would put a subsonic booster stage which enable the missile range of 450km to 500 km range. During booster stage it's travling at subsonic. The missile stealth faceting feature would allow it go undetected like the F-22.

At beginning of interceptor range, booster off, the missile turn its engine and begin to go mach 2. Interceptor come in close and target aware of that, make an acceleration to mach3, zoom past the interception point.

at 20km, CIWS turns on and firing the bullets, target's IR sensor aware of bullets coming in and make another dash from mach3 to mach4 bypass the bullets and CIWS probably got one shot at that and missed.

Kaboom, the missile hit the ship.

Click to expand...

you can't just accelerate from mach 3 to mach 4. The Russians had a bunch of problem with Club going from subsonic to supersonic from I read. And you are asking the missile to accelerate at least 3 times from your post. That takes a lot of processing and more importantly a lot of fuel.

Sunburn, as it is, is the most overhyped but far from the most useful missile in service with PLAN. Look at how huge it is to even travel at mach 2.5. If you want to make a missile that flies at mach 3 or 4, you have to get it to fly lo-hi-lo profile and it will still be huge. So in end up with something that's easy to detect, a large target. Modern CIWS can counter it. Especially something like Type 730 CIWS. A while back, I remember reading Phalanx getting modified to handle ballistic missiles going at mach 6. What you are mentioning is not any different.

Scratch said:

several points regarding RAM


I think the missile has a proximity fuse(?), so if it comes very close as you say, it might already detonate and release a lot of shrapnel impacting the AShM with high speeds.
Furthermore, your missile can't just "suddenly accelerate" from M3-M4. ManOverboard already stated the on/off part of missiles. Even if you could produce such a complex system in a missile (and high complexity isn't alway good) to accelerate that fast, you'd need an enormous amount of reserve energy.
I don't think a ramjet, or any airbreating engine could react that fast. That means additional rocket boosters, wich are again only dead weight before firing and also increase size.


Also the RAM isn't dumb at all, it is smart. It doesn't need the SPY, or any other foreign sensor at all once fired.
It's passive RF seeker senses the radar output of the AShM, and it's IR seeker sees the glowing skin of the missile body due to it's speed. That's all it needs, active radar homing is not necessary.
It makes all the calculations itself, and that takes rather milliseconds or even less. A M4 missiles "only" travels 1,3m in 1ms.


If you put it there, that means you have something like a small pod, wich also "stands in the wind". The flowing air will heat up there as well and maybe create a plasma.

If you want a cruise booster for subsonic speeds, the best/most efficient way is a small turbojet/fan. So in your case you might want to launch a small UAV wich carries and launches one AShM once in range. That UAV could then be designed stealthy.
Then the missile might be launched with a rocket booster that seperates, and the missile might start it's ramjet.
Besides the point that I find it hardly beliveable an onboard IR sensor would reconize incoming bullets, I already said I also don't believe you can just go from M3-M4 in a second.
Furthermore, the missile is trying to hit a ship, and the CIWS is on that ship. ManOverboard already said that's rather a head on engagement. If the missile accelerates, it will only fly faster into the bullets coming towards it.

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proximity fuse? ----the blast radius of rocket /w explosive is about 30 ft.
how far do you want you missile explode?


Acceleration?---- OK, maybe not be Mach3 -4 but let's say it accelerate. With non-constant rate


RAM calculated by itself within milliseconds? ----now that's a bit carried away. You are assuming a full set of computer on the small SeaRAM to do the mathmatical calculation. and then able readjust your fly pattern. Didn't man overbored says SeaRAm cannot adjust speed and direction. For CIWS 's its reaction is 6 seconds, S-300 20 seconds. from getting data to calculation prediction to launching missile.
where on earth you getting SeaRAM calculated for a firing solution within miliseconds? definitely give me some references and link pls.


As for CIWS, as soon as bullets launched which detect by target's IR sensor, it again accelerate on non costant rate. Target past the interception pt at time 0 whereas bullets lag behind and arrive at time1. Therefore missed.

lilzz said:

proximity fuse? ----the blast radius of rocket /w explosive is about 30 ft.
how far do you want you missile explode?


Acceleration?---- OK, maybe not be Mach3 -4 but let's say it accelerate. With non-constant rate


RAM calculated by itself within milliseconds? ----now that's a bit carried away. You are assuming a full set of computer on the small SeaRAM to do the mathmatical calculation. and then able readjust your fly pattern. Didn't man overbored says SeaRAm cannot adjust speed and direction. For CIWS 's its reaction is 6 seconds, S-300 20 seconds. from getting data to calculation prediction to launching missile.
where on earth you getting SeaRAM calculated for a firing solution within miliseconds? definitely give me some references and link pls.


As for CIWS, as soon as bullets launched which detect by target's IR sensor, it again accelerate on non costant rate. Target past the interception pt at time 0 whereas bullets lag behind and arrive at time1. Therefore missed.

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for naval guns, please read how the latest penetration shells operate and not make statements like this. There are different technologies solving all of this problems.

tphuang said:

you can't just accelerate from mach 3 to mach 4. The Russians had a bunch of problem with Club going from subsonic to supersonic from I read. And you are asking the missile to accelerate at least 3 times from your post. That takes a lot of processing and more importantly a lot of fuel.

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Isn't the Sunburn using Ramjet engine. The hypersonics is using scramjet engine. If you don't accelerate? how do you get from mach3 to mach4?
Let's say for Mach6 capable missile, it can't travel at slower speed and jump up to higher speed?
OK, let's just say it accelerate not necessary those numbers and it's nonconstant rate.

tphuang said:

for naval guns, please read how the latest penetration shells operate and not make statements like this. There are different technologies solving all of this problems.

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just imagine the bullets as a mini-missile. the prinicple should works the same.

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. 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.

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If the missile is jinking, which means it will take an angular redirection in any four directions other than straight ahead, you will lose forward speed, which becomes tangent to the angled direction. Feel free to rewrite physics text books if you wish

lilzz said:

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

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It can but can it identify them as bullets?

Let me clarify something about RAM. It has two modes, IR only, which is IR all the way, and IR Dual Mode, which is passive RF leading to IR on the later stage. It has no Passive RF all the way. In dual mode, the passive RF leads the missile to the general acquisition basket of the IR seeker, and then the IR seeker takes over.

Actually, passive RF against an antiship missile all the way is a very bad idea. Why? The way an antiship missile scans, it does it at frequencies and rates that is fine against big, slow moving ships, but is totally useless against small fast flying objects. And it cuts both ways, because that sort of radar isn't going to provide the tracking rates needed for a passive SAM (you will do better trying to passively track the radar of an active guided SAM or AAM). The general resolution is quite loose and big for a direct target, but at least it is enough to fall into the circular radius of an IR seeker's acquisition range.