Anti-missile test sucessful...

[Dr Mordrid]

SM3 passes another milestone;

HONOLULU, Hawaii (AP) --

The Navy intercepted and destroyed a warhead as it separated from its booster rocket during a test Thursday off Hawaii -- the first time a ship at sea has shot down a multi-stage missile.

The guided-missile cruiser USS Lake Erie fired an interceptor missile and knocked out the rocket's warhead about 100 miles (160 kilometers) above the Pacific, the Missile Defense Agency said in a statement.

The achievement is considered significant because medium- and long-range ballistic missiles typically have at least two stages. Intercepting such missiles after they separate is difficult because sensors must be able to distinguish between the body of the missile and the warhead.

All previous tests of the sea-based missile defense system involved short-range missiles that stay intact.

http://www.cnn.com/2005/US/11/17/missile.defense.ap/index.html

In a related story Poland and the Czec Republic are said to be considering the basing of a land based version of the new system. The intent would be to provide protection of Europe and American bases/shipping from launches originating in the Middle East.

Dr. Mordrid

[Nowhere]

Meanwhile Russians are developing countermeasures...

http://www.washtimes.com/national/20051120-115514-2217r.htm

Not a big deal really, if it'll be kept out of hands of those who don't care about mutually assured destruction...

[Fluff]

Is this the starwars thing?

[Dr Mordrid]

Fluff;

Semi-yes. The R & D is coming to a head and very soon the US will have directed energy and antimissile weaponry. A ground based version will be deployed within a couple of years in Alaska.

Deployment of the SM3 on existing Aegis cruisers and the upcoming DDX stealth cruisers ( http://www.ddxnationalteam.com/ ) will follow.

Nowhere;

a maneuverable warhead isn't enough against the SM3....it maneuvers to match its target and it doesn't have to perform a direct hit to make a kill.

As for the Russians; they aren't who SM3's intended for. It's intended for rogue nations using NK, Chinese or other old Russian tech as found in the third world.

More modern missiles will likely be targeted by the ABL (airborn laser) or other directed energy weapons as they launch. The recent development of a high powered solid state continuous fire laser strong enough to shoot down a target is one example.

Dr. Mordrid

[Nowhere]

Doc, that's a non argument to me - it's simply a matter of how maneuvearable and fast is the missile in relation to maneuvearibility and speed (that's the only things which is about constant here...) of the warhead.
And you have to admit that Russians have reasons to feel uncofortable...so they want to make sure that SM3 isn't intended for them.

BTW, how effective would be simply covering warhead with optical mirrors to fight lasers intended for downing it directly? Or perhaps they'll operate at wavelengths at which such approach won't be feasible?

[Dr Mordrid]

Reflective coatings have two problems. Basically they're;

1. imperfect

2. fragile

Reflectivity is a function of a micron thick layer at the surface and it doesn't take much short wavelength laser energy to turn it into something else. When this layer burns, melts, ablates or shatters from the lasers shock wave (a major shock wave in the case of laser weaponry) the reflective surface goes bye-bye.

Evidence of this is in how difficult it's been to construct mirrors that will survive being used in the laser weapon itself, and that's under sealed conditions. One small imperfection on a reflective surface exposed to a short wavelength laser beam and things look like a scene out of Real Genius.

Reflective surfaces would work against a long wavekength CO2 lasers. Here polished aluminum would deliver ~ a 97% reflectance. Even then maintaining such a surface after launching from a smoke filled launch would be iffy. Thing is CO2 or other long wavelength lasers won't be used in weapons.

Another way to destroy a missile with a laser is to make it collapse from a compressive load along its axis. The axial load has two sources;

1. atmospheric drag, which exerts a large force on the missile particularly as it exceeds the speed of sound.

2. the stress on the missile from its inertial load, which comes from the accelerating mass.

An al-Husayn missile passes Mach 1 when it is 30 seconds into its flight at an altitude of around 5-7 km and reaches its acceleration maximum of 7 m/s2 at burn out. If a laser inflicts a sufficient arc on the missile at this point the missiles structure will collapse.

Dr. Mordride

[Nowhere]

Hmmm...so I guess keeping warhead in hermetic casing and figuring out the way to jettison it (in a safe manner, that would leave the mirrors intact) once the thing is basically outside the thick atmosphere would have a big chance in succeding?
Probably will be a nightmare in engineering...especially in conjuction with warhead that can alter its course.

What about preventing detection? Coating warhead in stealth (radar) material that is kept at low temperature by liquid helium should do the trick, right? Just remember to also use helium for maneuvering, and not some rocket engine

edit: just have a thought...how superconductive material reacts when electromagnetic wave at radar frequency hits it? Would it help or, on the contrary, maximize detection?

[Dr Mordrid]

Note the edit adding in the effects of the laser on aerodynamic loading. Bad mojo.

As for preventing detection, not likely. Stealth is only partly achieved by the use of antireflective materials. Most of stealth is by shape, as in compound angles and curves in the shape of the aircraft. Missiles airframes aren't very conducive to this kind of shaping, and a slight rotation of its airframe could negate the effect.

Stealth is also totally useless against LIDAR....longer wavelength laser "radar", which would also throw all kinds of alerts from a reflective surface. This is just one of the advanced sensor systems being used in conjumction with radars, IR detection of the thrusters etc.

Jettisonable shields for the warhead work for a CO2 laser after the boost phase, but that doesn't help when the laser is short wavelength and/or targeting the missiles airframe during boost phase...which is target #1.

Hit the missile during boost phase and it's over; no warhead defense can help then and there is this HUGE heat plume to target the front end of.

Dr. Mordrid

[KRSESQ]

Remember that all of the things you suggest would add weight (however "negligible") to the entire vehicle, which would affect its range and/or terminal velocity and ultimately its accuracy as well.

To say nothing of the added expense!

Kevin

p.s. Not to threadjack or anything, but I googled the word "negligible" to check the spelling and this was at the top of the search results. Facinating! (And these guys are NOT quacks!)

[Nowhere]

Well, better armor in tanks also requires weight (at least that's one way to do it...), but to some extent it's worth it.

Anyway, those are just loose thoughts. Oh, and I'm wondering mostly about enemy that is around on par, technologically and when it comes to numbers. I'd guess that in such case the LIDARs and lasers capable of shutting down the missile while at start wouldn't be that helpfull, because of numbers of them required. So I guess anti-missiles directed by radars would be the only practical (also...financially) countermeasures.

[Marshmallowman]

I really do think reflective skins can and have worked well, you just have to make sure it reflecting the frequency/energy level that is being beamed at it.

And these skins don't have to be that fragile, and you can have an outer protective skin that just burns off to reveal the real reflective skin.

You can also use stealth like techinques to reduce the effect of laser , eg angled fusleage...etc. and you can angle this effectively becasue you could probaly guess where such lasers will be fire from in the missiles trajectory and hence orientate itself to use it surfaces effectively.

These lasers systems still have a long way to go....

[KRSESQ]

Well, better armor in tanks also requires weight (at least that's one way to do it...), but to some extent it's worth it.

Tanks don't fly.

Kevin

[Nowhere]

Oh c'mon, you know what I mean, same basic rules apply here.

[KRSESQ]

Oh c'mon, you know what I mean, same basic rules apply here.

Not hardly. Tanks are deliberately designed to be big, massive, heavily armored beasts to protect the crew inside so they can attain their objective. Weight is an issue only on unstable ground where the tank would get bogged down. Missiles on the other hand have to go very fast and very far and deliver a payload with (relative) pinpoint accuracy. The main advantage of tanks is armor which may or may not protect it from hostile fire. The main advantage of missiles is their speed which hopefully will put them on their target before the enemy can respond. They have entirely different purposes and mission profiles. They are about as comparable as bicycles and airplanes.

Kevin

[Nowhere]

We were not talking about tank-style armour. We were talking about small weight increase, which could be easily countered by other decisions in design of warhead/missile (for some cost...). Overall: about how one change in construction, which is good generally but causes one negative effect, can be countered in other areas.