I know this is outside my usual subject area, but I just saw a spectacularly stupid quote from moronic conservative, and I just had to mock it.
From AllThingsConservative, an explanation of why we should thank god that Ronald Reagan was president:
If not for Ronald Reagan, and his vision and leadership, we would now be at the mercy of that lunatic in North Korea. Instead, we have a workable missile defense against the threat. Not only are we still working on a space-based system, but the technology now being deployed was developed due to the efforts started by Reagan.
We should definitely shoot down the test missile.
Y’see, if if weren’t for the fact that Ronald Reagan was president, we wouldn’t have spent billions of dollars building a missile defense system that doesn’t work. And if we didn’t have a totally non-functional missile defense system, then we wouldn’t have the kind of safety that only a non-functional missile defense system can provide.
After all, remember: this is the missile defense system that hasn’t been able to knock down a missile even under the most insanely favorable conditions. A system that has failed a majority of its tests, even when they knew exactly what trajectory the incoming target was going to take and the target missile was carrying a homing beacon.
Yup, we can all sit back and feel secure in the knowledge that we’re being protected by the genius of Ronald Reagan. Because if the North Koreans tell us exactly when they’re going to launch a missile at is; exactly what trajectory they’re going to use, and they’re kind enough to put a homing beacon on the warhead, we’ll have a slightly less than 50% chance of successfully shooting it down.
I feel so greatful, don’t you?
There must be a way to connect the “non-functional missile defense system” with their “erectyle disfunction syndrome”, methinks. It has to do with rockets and shooting….
I hear Ronald Reagan could beat-up four communists while still reading the morning paper with one leg shackled to a nuclear reactor.
All we have to know is where it isn’t, then we’ll know where it is, by taking the difference. Or something.
A couple of notes. First, Reagan did not start the missile defense program. It had and has been going on since the ’50s. That avatar of ignorance simply didn’t know about it. All he did was make it well known and very well funded. Second, the current system has hit test targets. You can debate the legitimacy of the test conditions, but an interceptor has hit a target. Of course that is a far cry from our “operational” system hitting an incoming NK missile.
anon:
Yeah, the current system has hit targets; that’s why the whole line about “If we know the trajectory, and if we put a homing beacon on the warhead, then we have a less than 50% chance of hitting it” shtick in the original post was about.
I don’t recall the exact success rate; it’s definitely under 50% success, even with the tests fixed to be absolutely bizzarely easy. I’m not joking about this: this missile defense system has a less than 50% success rate with a damned *beacon* in the warhead for the missile-defense system to target on.
And it’s not operational by any reasonable definition of “operational”. The purported excuse for the homing beacon in the warhead? The targeting system of the anti-missile defense system relies on a system of radar installations that do not exist to provide enough information to accurately target an incoming missile. Since those radar systems have not yet been built, the information that they would purportedly provide in an operational system has to come from *somewhere*, and so they put a beacon in the warhead that broadcasts its location.
Why do the radar stations not exist? Because they don’t work yet. So far, they have not been able to get the multiple stations working together correctly to be able to provide the kind of precise data that is needed. It’s possible in theory, but the implementation thus far has been unsuccesful.
The missile defense problem can be broken up into the theoretical and the engineering. Getting an interceptor to hit a specified target is just an engineering problem. It is not easy, but it’s also not harder than many engineering problems that have been solved reliably. The US government has been working on the engineering part of the problem for about a half a century and has not solved it yet, although most of the constituent parts of the problem have been solved. For example, we can launch missiles, and we can find objects by radar. We can direct objects to locations many millions of miles away. What other engineering problems have not been solved after that amount of time and the tremendous amount of money expended?
Now, the theoretical part is mainly figuring out how you specify the right thing to aim at. That’s been worked on for the same length of time, but it’s an entirely different can of worms.
anon_again:
It’s not quite as simple as that.
Even the engineering parts are very hard. The problem that the homing beacon in the tests was supposed to work around isn’t such a simply-solved problem as you make out.
What you need to realize is just how hard the math really is. If you’re trying to track an incoming ballistic missile, you need to work out not just where the warhead is, but where it’s going to be. To compute the “going-to-be” part, you need to compute its velocity; and radar systems don’t measure velocity – the velocity needs to be computed, and it’s constantly changing, as a result of steering thrusts, gravity, wind, etc. So you need to be tracking it simultaneously using multiple radar bases in distinct locations, transmitting and combining the information, and using it to figure out where the target is going to be when your ground-based weapon reaches it.
That is not an easy task, when you realize just how fast and how small the targets are.
> this missile defense system has a less than 50% success rate with a damned *beacon* in the warhead for the missile-defense system to target on
I talked to a guy who was working on this system. He says that data from the beacon was used after the missile test (not during the test) to figure out how close the interceptor came to the missile.
> To compute the “going-to-be” part, you need to compute its velocity; and radar systems don’t measure velocity – the velocity needs to be computed, and it’s constantly changing, as a result of steering thrusts*, gravity, wind, etc
Kind of like the patriot missile system except that the missile is travelling faster?
* A ballistic missile uses thrusters only during the first part of it’s trajectory. The majority of it’s flight is spent in free-flight and re-entry, without thrusters. As a result, it follows an elliptical flightpath.
Doonesbury had some wonderful quotes about missile defence, both during the first “Star Wars” heyday and during its more recent renaissance. “My daddy says that with enough money, the Pentagon can build just about anything.”
“Apparently, a reliable cheat is still some years off.”
BC:
It’s an interesting fact that there have been rather a lot of different explanation for the beacon in the missile. None of which actually make much in the way of sense. A homing beacon in the missile isn’t a good way to solve any of the problems that it’s been reported to solve.
WRT the ballistic missile: the theoretical operation of a ballistic missile is that it thrusts at takeoff, and then goes thrustless – purely ballistic – for the rest. However, the reality is that that’s *not* how they work. They don’t go through dramatic accellerations after takeoff. But they *do* go through various kinds of course changes – some for correction of its trajectory, some for throwing off tracking systems, some from the accelerations caused by separating the warhead from the missile, some by air-resistance, winds. In the real world, there is no real perfect ballistic trajectory.
Surely if you’re firing a ballistic missile at someone who claims to be able to shoot down ballistic missiles (particularly if they claim the math of predicting their position is simple) then one of the cheaper solutions (assuming you’re stuffing a nuclear warhead onboard and/or don’t care much for pinpoint accuracy) is to make the trajectory not so ballistic.
And this has always been the central argument against the feasibility of anti-ballistic missile technology. It’s not that it’s impossible to hit a ballistic missile. It’s that there are so many simplifying assumptions, any of which can be violated with some relatively simple spoofing system.
Don’t want a ballistic flight path? Jink around a little (as long as you know the characteristics of your in-flight variance from a ballistic path you can still hit targets). Add some decoys that *are* ballistic. Vary vector during the boost phase to increase calculation costs in the ballistic phase. Swing out wings in the final phase and start gliding a bit. Drop chaff and flares. Add air brakes that open and close at pre-programmed intervals. I’m sure an actual ordnance engineer could readily come up with a much longer list.
I’m willing to bet the US missile defense can shoot down a ballistic test missile from North Korea that is targeted roughly nowhere. I’d also bet that a genuinely hostile missile attack would have zero chance of being struck. Better to pray for bad weather.
BMurray:
Yes, exactly. The simple fact of the matter is, in theory, a ballistic missile is only accellerating under its own power during the initial launch phase; but in reality, it’s stupid to pretend that that’s somehow a meaningful model of the behavior of a real ballistic missile.
The tests thus far of our so-called missile defense system, the tests at which it has failed so much of the time, are unreasonably simplified.
Anyone who is capable of producing a true ballistic missile is capable of adding an extra five-pound tank of compressed air. Which is all that you need to produce enough acceleration to shift the trajectory of the missile by the hairs-breadth margin necessary to cause an intercept to fail.
Anyonewho is capable of producing a ballistic missile is capable of throwing two dozen one dollar mylar balloons into the missile with the warhead. All of the technologies that we have developed so far for targeting a warhead cannot distinguish a mylar balloon from a warhead during the ballistic phase. (In tests, we use a warhead with one or two distraction targets, and the distraction targets are dramatically less bright than the real target – so the algorithm is “look for the brightest target”. Know how to counter that brilliant strategy? Paint the real warhead black.
The missile defense concept may be an interesting one; but the technology to create an acceptably effective one does not exist at present; and the work that has been done on it is not at all encouraging to anyone who looks at it carefully. We are presently incapable of building a missile defense system that provides us with any meaningful protection, even from an unsophisticated enemy. With no countermeasures being employed to confuse our so-called missile defense, we can’t even hit the target half the time; and the countermeasures that can reduce the effectiveness of the system from 30-50% to near zero are trivial. (Air tanks to provide tiny accelerations; mylar balloons as decoy; paint to reduce visibility; water tanks to produce a short-lived fog of water droplets; phosphorus flares to produce an accelerating decoy; etc.)
All that the missile defense system does at present is breed false security among morons. Unfortunately, some of those morons are people in positions of power and authority, and allow that sense of false security to influence their decisions.
What some of you may not realize is that many of the programs that were developed and tested under the SDI program are in place as scaled down versions today.
The AEGIS system including the AN/SPY-1, ACS, CDS, WCS systems, on the Arleigh Burke class Destroyers were in design phases when the SDI came about. Advances in technology and funding due to SDI allowed the first AEGIS DDG to enter service in 1991, years ahead of scheduel. AEGIS is the most advanced missile/anti-missle system in existence today. Two well placed AEGIS cruisers in the Sea of Japan could take our a short-range ballistic missle in its ascent stage, and I assume you missed the test of this system just last week that destroyed a ballistic warhead in space before re-entry into the atmosphere.
Other technologies, too numerous to list, including sensing, detection and tracking technology have emerged or been significantly enhanced by developments under the SDI/BMDO/MDA programs. Project still under developemnet include the Airborne Laser system and the Kenetic Energy Interceptor have advanced significantly.
Aslo, radar technically cannot tract velocity, however radar systems, especially phased array radar, can track, determine and predict velocity very accurately. Examples, AEGIS AN/SPY-1, Patriot MIM-104 AN/MPQ-53 or -65, MK 15 Phalanx CWIS.
CC:
My basic point is pretty specific: I’m pointing out the stupidity of the notion that somehow, we don’t need to worry about North Korea and its missiles, because we have a missile defense system.
Even with the latest successful test, the overall success rate of tests of our missile defense system is under 50%; and that’s using tests that have been set up to be easy.
There’s nothing insurmountable about building an anti-missile system. But there’s a lot that’s damned difficult. And with the technology that we have today, *I doesn’t work*.
At the speeds that these are moving at (e.g., wikipedia states speed at impact as roughly 6 km/sec), miniscule deviations in the trajectory are enough to provide an effective counter to ABMs. A total lateral acceleration of 1/2 of 1 meter/sec – which is a very easy amount of accelleration to generate – is enough. And primitive BMs are quite inaccurate, because the re-entry phase involves a lot of erratic acceleration; in the case of a primitive BM, the targeting error cause by the trivial accelleration in ballistic phase is lost in the noise of re-entry; in more sophisticated BMs, the amount of acceleration needed as a defense countermeasure is trivial to cope with once they’ve been developed to the point of being able to adjust for the problems of re-entry.
The current missile defense system requires a system of dispersed radars in order to be able to track and compute velocity and acceleration. That grid of radars has not yet been built – meaning that unless the target has a beacon inside of it, we can’t target it.
The radar systems proposed for the missile defense system can’t tell the difference between the warhead and a set of dirt-cheap decoys. Quite literally, the $1 mylar baloons they sell at your local grocery store produce a radar echo that’s quite hard to distinguish from the radar echo of the real warhead, until the warhead starts re-entry; but our targeting system is only designed for hitting the missile *before* it starts re-entry; the erratic accelerations of re-entry (which are what allows us to distinguish the warhead from the decoys) make targeting unrealistic during that phase of flight.
The point of all of this is: the current so-called missile defense system is not a meaningful defense system in any way. It barely works in conditions where every variable has been biased in its favor; and it can be totally overwhelmed by the most trivial countermeasures.
We are no safer from the threat of a missile attack from the loonies on North Korea than we would be if this missile defense system had not been deployed. Because this system does not work.
Not true. During the test last week a Standard Missile Three (SM-3) was launched from the guided missile cruiser USS Shiloh (CG-67) during a joint Missile Defense Agency, U.S. Navy ballistic missile flight test. This is the seventh successful launch/kill from that platform. This system does not use a multi-level dispersed radar system to track and predict balistic missile trajectory. The USS Shiloh detected the missile shortly after launch. Her own phased array AN/SPY-1 system tracked and successfully engaged the missile before it reentered the Earth’s atmosphere.
Here is the article:
Missile Defense Test Yields Successful ‘Hit to Kill’ Intercept
LMAO — the interceptor will undoubtedly be running a multiple hypothesis testing bank of kalman filters. since mylar baloons don’t fly like BMs, they’d be trivially rejected by a good estimation filter.
wrong. Good radar seekers measure range-rate very well (essentially by looking at the doppler shift caused by the relative closing velocity)
You seem to have the incorrect assumption that the estimation-guidance-control piece of the intercept problem is insurmountable. Actually we have off-the shelf technologies to solve all these things. The engineering problem is finding a solution that does it cheaply enough — its simply not a question of “can we do it”.
You also seem hung up on the “50%” effective number. In total so far yes — but success in 7 out of the last 8 tests isn’t fairly considered a 50% success rate. What the tests show is that the US is learning from early errors. Each subsequent success, in incrementally more challenging test scenarios, shows that this system can work.
I would also note that the current payload used on the SM-3 missiles is a kenetic only impact weapon. This means that the system has to be extremely accurate in it’s acquisition, tracking and firing solution. We have other warheads such as fragmentation and high explosive which will reduce the accuracy requirements. The MDA/USN testing chose to use the kenetic only warheads during testing. This forces the system to test with the least margin for error, since to successfully kill the warhead the missile must directly impact with significant kenetic energy to destroy the weapon.