All posts by Number9

U.S. Hypersonic Strategies Part 5

Why can’t we put a space cadet from the newly formed Space Force in the nose of the interceptor, and have him shoot at the warhead as he zooms by? Intuition fails us with the speeds and acceleration. The space cadet would be mashed flat in the high-g blast-off. The speed of his bullets is 1/10 the speed of the target, almost as slow as the mail.

The hit-to- kill vehicle  is  devastating in head-on collision. The energy delivered to the target is the kinetic energy of the vehicle,   much large than the energy of an explosive charge. Purity of the concept is of no concern,  so one of the ways to turn a miss into a hit is an explosive charge that fragments the kill vehicle in front of the warhead.  Another enhancement, workable only outside the atmosphere, is an extensible “cow catcher”.  Both replace the head-on collision with smaller but sufficient mass to break  the target. Aerodynamics and the heat of air friction do the rest.

What kind of fragment, or other small object, is sufficient to destroy a warhead just from being in the right place at the right time? At collision speed, the kinetic energy is about the same as equivalent weight of TNT. But our study so far has been amenable to napkin calculations because of the binary definition of success, hit or miss. Materials lack that certainty. We don’t theorize about tank armor versus penetrating round; we try it out. The behavior of materials in extreme conditions is an experimental science.

Space junk and micrometeorites pose a threat to satellites. Shielding is thought to be practical up to an asteroid size of 1 cm. The shield is a double wall. The first wall shatters the asteroid into smaller pieces that cannot penetrate the second wall. But an asteroid is not engineered material. The toughest asteroids are nodular iron, which isn’t very tough.  Most are chondrites, made of small grains cemented together by pressure. A shield may be effective against the bulk of satellite debris. But a  titanium bolt, left over from an anti-satellite missile test, is an engineered material, with far greater penetrating power than a clod of dirt.

The small chance of a  pure hit-to-kill against a maneuvering target might be improved by release of a cloud of small engineered objects, with sufficient density and  to insure an impact. The calculation of Part 4 can be repeated with a “hit” expanded  to the vicinity implied by the size of the cloud. This is standard with anti-aircraft missiles. But aircraft are the ultimate soft targets. It doesn’t automatically imply destruction of a warhead hardened against reentry. We have to think about it.

If a pack of high-tech BB’s were released in front of a hypersonic vehicle, would destruction result? Unlike the hit-or miss proposition, it depends upon details: shape, material, thickness, internal structure, and warhead vulnerability at point of collision. The BB’s could be the densest, meanest BB’s imaginable, tungsten with a depleted uranium center, yet success is not assured.

If a BB craters the surface, or puts a hole in it, it could disrupt aerodynamic control, or cause local heating, leading to destruction. Some obstacles to success:

  • As soon as the BB’s are released, they are blown backwards in the air stream, losing kinetic punch.
  • A hypersonic warhead has sharply sloping sides. Like the sloping glacis of a armored tank, the impact energy is reduced by the sine of the impact angle.
  • The properties of carbon fiber plastics, of which Avangard is said to be made, can be vexing, as the Russians have discovered. But they also offer complex opportunities for manipulation, of strength and cleavage properties that vary sharply with angle.

Once the rivalry gets going, Avangard, or other hypersonic vehicles, could be equipped with “spare parts.” If there’s a lucky shot to the tip of the nose, it falls off, revealing — another nose. Unlike the original missile race, the Russians have plenty of throw-weight, which can be diverted to armor Avangard, and descendants, against threat.

A counter to plastic armor could be an ingeniously engineered micro-projectile.  A pointed shape, concentrating impact force, might be stabilized in the right orientation by a dispenser that imparts spin, or by a magnetic pulse.

Suppose we pass over the idea of a penetrating BB in favor of gumballs.  I’ve spent my life scraping these things off my shoes.  A gumball is a projectile with a soft core,  still very massive, to resist the aerodynamic forces of the slipstream.

When it hits Avangard, the gumball goes “splat!”, and  the soft, chewy core sticks on it, quickly setting to an adherent, thermally conductive ceramic. This disrupts the crucial thermal balance of the surface. Frictional heating does the rest, burning a hole, or causing thermal-mechanical stress fracture, a virtual guarantee of destruction.

Without frequent access to a test article, ie., a stolen Avangard, we’re working in the dark. But it is at least conceivable that a micro-projectile could,  by a chain of effects, be as damaging as a direct hit.

Next: Beyond kinetics: directed energy, nukes, and hybrids.






U.S. Hypersonic Strategies Part 4

Let’s put another nail in the coffin for kinetic-kill vehicles. An EKV (exoatmospheric kill vehicle) has a  chance only if the adversary warhead climbs above the atmosphere for some portion of flight, and Avangard may never do so. If a hypersonic warhead descends enough to maneuver in flight, that contest is over.

There is a little bit of high school level math. If this turns you off, Part 5 will return to a qualitative presentation.

At lower altitudes, a winged interceptor missile, like the hypersonic adversary, can convert some forward motion into maneuvering energy. The DARPA RFPs will naturally include enhancements to winged interceptors. The logic: To intercept a hypersonic warhead requires a hypersonic interceptor missile. This means bigger, faster boosters, and a missile shape with more aerodynamics  than the vestigial fins found on today’s interceptors. Something like the Boeing Waverider on top of a Sprint booster.

There is  a major fly in the ointment. Suppose that after some years, both sides have squeezed all they can out of air frame  propulsion, and guidance. Missile development, like everything that depends on physics, is subject to the law of diminishing returns. Novelties can only delay the inevitable. It then becomes an even match,  except for one thing. The warhead knows its evasion plan. The interceptor has to observe, and estimate.

The interceptor, combined with ground-based tracking, estimates (I did not say knows) the position of the warhead. To figure it out, the interceptor thinks that:

  • Position is anticipated by velocity, which is  combination of speed and direction. So we need the velocity of the warhead.
  • Velocity is anticipated by acceleration.(The accelerator pedal in a car, and turning the steering wheel both produce acceleration.)
  • Acceleration is anticipated by jerk, which corresponds with how your foot is jiggling the accelerator pedal and twisting the steering wheel.

Jerk”, corresponding to the warhead’s next move, is known only to the warhead. What goes on in the warhead’s little brain cannot be eavesdropped. All other things equal, the warhead has the advantage.

A typical mutual closing velocity is 10,000 meters/second, split between the warhead and the interceptor. Suppose a hypersonic warhead makes this maneuver:

  • Change of course  100 milliseconds before impact, when separation is 1000 meters.
  • Converts 1% of its forward velocity, 5000 meters/second, into lateral  velocity, 50 meters/second, over 75 milliseconds.
  • A change of 50 meters/second in 75 milliseconds is an average acceleration of 66g’s. For comparison, a Sprint missile accelerated at 100g’s, impossible for humans, but comfortable for a compact, hard warhead.

Without a course change by the interceptor, it misses by about 5 meters. To correct course requires an accurate prediction. It has a camera on the front,  and a computer to interpret the images. The computer runs a program, an algorithm, to figure out the new anticipated intercept point  from a mess of data.

Now here’s a WAG of the prediction problem, where for clarity I have made certain simplifications about “filters”:

  • Position, velocity, acceleration, and jerk are coupled together.  For this problem, we need them all to get one.
  • To get all four variables requires a minimum of 4 observations. Remember your simultaneous equations from high school: 4 equations for 4 unknowns. Call each of these an observation set.
  • To get decent accuracy, we need at least 3 sets, probably more. A total of > 12 observations.
  • When a sensitive sensor, CCD or CMOS, images a point of light, it blooms, with expanding bright halos that fuzz the position of that point. Allow 10 milliseconds for the bloom to fade before another observation can be taken. Total time to observe: >120 milliseconds.
  • Time to run the program to come up with the new position and compute how the interceptor should respond by actuation of thrusters and control surfaces: 80ms.
  • Total time: 200 milliseconds.

Now the interceptor alters course,  by adjustments that require more time, to signal actuators, such as control surfaces and thrusters, which require more milliseconds. A thruster needs 2 ms just to start, and more to stabilize.

In that 200+ ms, the warhead and interceptor, moving at  closing velocity of 10,000 meters/second, have moved a further 2000 meters, 6000 feet. In the blink of an eye. And the warhead may change its mind again while all this is going on.

The above describes a scenario where the interceptor almost works, but not reliably enough to save a city. How much money do you lay on the interceptor? It has to hit to win. The warhead only has to miss.

To the above, we can add a corollary of Murphy’s Law:  Everything works a little worse than designed.

Next: Is there a game-changer?







Has Kim Jong Un executed top envoys over his failed summit with Trump?

(CBS)Has Kim Jong Un executed top envoys over his failed summit with Trump? Maybe, maybe not.

In the good-old-days of the Forecasting World Events intelligence crowd sourcing project, this would have been prime material. Quoting,

Friday’s report is based on a single, unidentified “source who knows about North Korea” – with no details about where that source got their information. The report so far hasn’t been matched by any major media in Seoul or confirmed by government officials, even anonymously.

It sounds like a bad way to source  intelligence, but with North Korea, it’s the norm.  My approach in the FWE program was to find a strong logic, and let it imply a conclusion, hopefully without subconscious bias, which in the case says, “ridiculous!”.

The media touts  embarrassment as the reason. The word hides too much, while the logic is painfully clear:

  • North Korea is starving.
  • The apparent cause is Kim’s inability to negotiate relief.
  • The basis to challenge to his power is clear.

The executions serve two purposes:

  • Deflect the responsibility for the state of the country onto others.
  • Intimidate those who might harbor the most secret thoughts of rebellion.

The logic says the envoys were executed, not out of embarassment, which is a social term, but to reinforce “truth” as it is dictated: Kim Jong-un is never wrong. Is the logic truthful? That was the nut of the FWE game.  If so, it’s a twisted confirmation of the CIA assessment that Kim is not insane.

In many cases, when dealing with unreformed dictators, moral judgments are a distant second to the  main objective. In this case, it is highly relevant. If the lives of process negotiators have no value, then in North Korea, process has no value.

North Korea cannot be trusted to implement any form of process; it is simply alien to their leader. Secretary Pompeo, I feel for you.

Saddam Hussein was more of a hands on guy. He took a guy out of a meeting into an adjoining room, shot him dead, and continued the meeting.





Top defense official suggests Russia violating nuclear test ban treaty

(CBS) Top defense official suggests Russia violating nuclear test ban treaty. Quoting,

When pressed on the allegation by Journal reporter Michael Gordon, Ashley would only say Russia had the “capability” to conduct very low-yield nuclear tests, a capability which Russia, China and the United States have long possessed, according to the Arms Control Association. He did not say whether Russia has conducted or is conducting such tests.

In the early days, as with North Korea today, a test was conducted at the end of a zig-zag tunnel, extending  horizontally into a mountain. The zig-zags cause the tunnel to collapse with minimal leakage. At the end of a  tunnel branch is a test chamber. At a minimum, the chamber must hold the “gadget”, and the monitoring equipment.

Tunnel excavation is accomplished with mining machinery, or, as in North Korea, with slave labor. In the U.S., in the late 1950’s, tunnels were replaced by vertical boreholes, requiring far less manpower, and without  risk to life.

The test chamber of a borehole is the width of the hole itself, so a standard oil rig cannot be used. The U.S. has special large-diameter rigs for test boreholes, and prefabricated instrumentation packages to  fit. The diameter, on the order of 6 feet, allows no  extra room to cushion the seismologic signature of the explosion. Hence even very small explosions above zero yield can be distinguished.

At last inspection of the active-till-1989   Semipalatinsk Test Site in Kazakhstan , Soviet underground tests were still conducted in tunnels. Lacking specialized large bore drills, this remains the Russian approach today.

A chamber inside a mountain is not subject to a fixed size. It can be excavated to whatever size is required, subject only to the load-bearing capacity of the rock. A cavern of modest size can damp explosions in the range of bunker busters, around 100 tons.

For maximal disguise, the objective of the Russians would be to create a seismologic signature that cannot be compared to preexisting data in U.S. possession. By choice of absorbent fill material, the seismologic signature can be further diffused and disguised. Fill  avoids the signature of a cavern collapse. Once you’ve heard one of those, you’ve heard them all.

The inconclusive  evidence, which cannot be dismissed, likely consists of:

  • Seismological signatures that, because of lack of comparison data, cannot be definitively classified.
  • Other forms of intelligence about which I will not comment.





(CNN, NYT) Navy pilots speak out on UFO sightings

(CNN) Navy pilots speak out on UFO sightings.

You might have a look at these articles, of which this is a continuation:

Since you are human, your brain is adapted to understand the world in a certain way that helps survival, but has nothing to do with science. This is why thinking about UFOs tends to the conventional, preferring solutions that represent improvements on what we already have.

The video includes objects moving with agility exceeding any physical object. Since this  is a DoD release, due diligence has been exercised to exclude:

  • Hallucinations.
  • “Ghost images”, also known as “lens flare”, which result from stray light bouncing around inside a lens.
  • Electronic errors within the sensor or image processor.

You can share the experience with a focused flashlight in a dark room. Flick it with your wrist, and watch the spot on the wall move with a quickness that a physical object cannot. The spot on the wall could be interpreted as a physical object, except that you know otherwise.

In UFOs: Let’s Get Serious; Why a Program Goes “Black” Part 2, I wrote,

What if an alien vehicle were not physically located where it appears to be? If it was a projection through a rent in space time, could we make sense of it by our tools of observation? What if the very fact of witnessing an event does not fit our conception of logic, which goes back to Aristotle?

Part 3 offers a list of possibilities. It may be too conservative. Most of it dates to classic sci-fi, in which relativity and space-time are favorite topics, but quantum mechanics is not. Going radical,

  • Fancy physics, yet in accord with material presence in our supposedly objective universe. This tends to focus on elaborate distortions of space-time, so the occupants can withstand being thrown around at thousands of gees.
  • Projection into our universe, through a “rent” in space-time. Some of the physical properties are carried along while others are not.
  • Hints of the physical, but with contradiction in logic as we know it.
  • A complete breakdown of objective reality, a core idea of quantum mechanics.

Since government UFO investigation began in 1948, not one iota of physical evidence has been recovered, other than spots of light on film, sensors, and retinas. This could be blamed on primitive equipment. From Part 3,

Since we have no fenders that fell off UFOs, how can we get a hint of whether they are material? If you have a sick child, you touch your kid’s forehead with the back of your hand. Heat receptors in your skin detect the fever. Regardless of whether your child has a fever, your child has a temperature. All material objects have temperatures. Actors, projections on the silver screen, do not.

Part 3 discusses how common laboratory instruments provide the basis to study this question:

Do UFOs have any attributes of physical objects?

The obstacle is that laboratory instruments are not designed to fly and engage rapidly moving targets, while military imaging hardware is highly specialized. Some newer imaging equipment is  hyperspectral, but the vast majority of it is not. Yet without it, we haven’t even started. Hyperspectral data is required to address the question.

Now suppose the question is properly studied, and no evidence of physical objects emerges, or the picture is quasi-physical, such as

  • Light without heat
  • Heat without light
  • Mass that comes and goes.
  • No convergence towards objective truth.

We might then be forced to concede that the underpinning of scientific thought, that objective reality exists, is deeply flawed. The Universe could be the biggest liar of all.

The Nature article, “Quantum theory cannot consistently describe the use of itself”, describes a paradox. In the situation contrived for the experiment,  observers must disagree. Have a look at the pop article, (Futurity) Thought experiment paradox divides quantum experts.

As with the “Schrodinger’s Cat” paradox,  there is a tendency to reject the implication, that objective truth is a weak concept. The alternative is a universe with the means to lie.  But what’s the motivation?

The motivation might come from what has been cited as a most basic principle of the universe, the Principle of Least Action, which shares a motivation with the programming technique lazy evaluation: to do as little as possible. Think, perhaps, of a chess game where the pieces are not moved when they should be, but only when a discrepancy would change another piece. If you imagine that the entire universe is a computer program, lazy this-and-that economizes on the size of the computer.

So things that happen when you are not looking might follow rules different from when you are looking. Anyone with a child knows this. A lot of people, including Einstein, dislike the idea that we live in a world where magic is possible, and might be common. In the end, we are frustrated by our human selves, with brains evolved to organize the world along the lines of objective truth.

As physics  grapples with the unknown and possibly unknowable, the concept of objective truth may end up in the trash. UFO research of substantial technical means, going beyond the search for sheet-metal wonders, could play an important role.

The most radical form of illusion was proposed by Ludwig Boltzmann in 1896.





U.S. blames Iran for tanker attacks

(Reuters) U.S. deploys more troops to Middle East, blames Iran for tanker attacks. Quoting,

[Rear Admiral Gilday] “The attack against the shipping in Fujairah, we attribute it to the IRGC,” Gilday said, explaining that the Pentagon attributed limpet mines used in the attack directly to the IRGC.

This was foreshadowed on 5/13, in Iran Fires the First Shot in New Tanker War. Quoting,

For a possible solution, we must reach back to the U.S. Civil War, when the modern self-propelled “torpedo” did not yet exist. The spar torpedo was an explosive charge on the end of a stick.  It was rammed into the target ship, and exploded not instantly, but shortly after the attackers got away. Just before World War II, the Brits invented the limpet mine, which holds fast to the target with a magnet.

These are examples of weapons which leave behind little in the form of traceable scrap metal. Both are historically associated with midget (or littoral) submarines such as the Ghadir.

The hypothesis of execution directly by the IRGC  was initially contradicted  by the “proxy hypothesis”, while the limpets were challenged (5/18, Insurer says Iran’s Guards likely to have organized tanker attacks) by underwater drones.

Underwater drones  had/has the attraction of support from forensic analysis, which may have been faulty. The proxy hypothesis seemed weak. Where would they shove off from? Quoting,

The nearest port, Al Mukalia, is 2160 miles, but it’s under UAE control….The Houthis don’t need a port to mount the attacks. They could have shoved off from a beach, and slowly motored their way 1600 miles. But the choice to label the IRGC as the enabler, as opposed to the attacker, appears to be an unsupported complication.

If the proxies were based in Iran, armed with Iranian weapons, and guided by Iranian radar, are they proxies in any sense of the word? How would their nationality be known, by other than HUMINT, which can be very unreliable?

Now we’re back to limpets, while the proxy hypothesis appears to be fading a little. Further forensic examination may not have supported the drone hypothesis, which requires more foreign debris than limpets. Execution by proxies may have been challenged  by additional intelligence that cannot be revealed.

While Occam’s Razor is never a fact, it fosters reexamination of complexities. Sometimes a simplification pops out of the jumble.

On the other hand, this could be Groundhog Day.

(Reuters) Ex-U.S. marine held in Russia on spying charge says he’s being threatened: TASS

(Reuters) Ex-U.S. marine held in Russia on spying charge says he’s being threatened: TASS. That’s (ABC) Paul Whelan‘s statement to the court.

Why would TASS, which is owned by the government of Russia, report prisoner abuse?

It’s an invitation to trade. Trades have been done many times in the past, but the TASS mention suggests they want to expedite.

Who have we got? Maria Butina, comes to mind.

How China tries to Hack Intel9, Consider Huawei

Some readers in undecided countries may require visceral evidence of the Huawei hazard. While hacking a website is old news, China is a  corporate state where hacking is a tool generally employed. The hacks documented below have limited effect, because, with the exception noted by Bloomberg, China has not infiltrated U.S. server infrastructure at the hardware level. Quoting (Bloomberg) New Evidence of Hacked Supermicro Hardware Found in U.S. Telecom,

A major U.S. telecommunications company discovered manipulated hardware from Super Micro Computer Inc. in its network and removed it in August, fresh evidence of tampering in China of critical technology components bound for the U.S., according to a security expert working…

There are many ways to hack a website. Since the security of commercial servers is professionally maintained, the softer target is the client software hosted on a server, as exhibited below. It originated today from IP, which by reverse-DNS lookup, resolves to “CHINA UNICOM China169 Backbone, Beijing.” Although there are many kinds of attacks, this typifies  the thousands of occasions in the website log  of hacking attempts.

China hackers of Intel9 showed little interest in geopolitics. The intensity of attacks seen by Intel9 spiked in reaction to technical content. Conversely, Russian interest correlates more with their refined approach to HUMINT.

Each line below represents an attempt, this morning, to access a nonpublic file at the core of a WordPress installation. The location of the file is on the left. The result code, “404” indicates that the  attacker failed to access the file.

//x.php                                      404             05-21-19 11:56 am
//lx.php                                    404              05-21-19 11:56 am
//plus/mybak.php               404             05-21-19 11:56 am
//data/cache/flye.php      404             05-21-19 11:56 am
//plus/read.php                   404              05-21-19 11:56 am
//plus/lucas.php                  404             05-21-19 11:55 am
//data/cache/asd.php       404             05-21-19 11:55 am
//plus/laobiao.php             404             05-21-19 11:55 am
//fdgq.php                               404             05-21-19 11:55 am
//Config_Shell.php              404            05-21-19 11:55 am

The attacks failed, in large part because China has not, at least on a  large scale, infiltrated server hardware. Such infiltration embodies the Huawei threat.

Reuters: Insurer says Iran’s Guards likely to have organized tanker attacks

(Reuters) Exclusive: Insurer says Iran’s Guards likely to have organized tanker attacks. Quoting,

– The similarity of shrapnel found on the Norwegian tanker to shrapnel from drone boats used off Yemen by Houthis, even though the craft previously used by the Houthis were surface boats rather than the underwater drones likely to have been deployed in Fujairah.

This is an attractive idea.  The insurer, Norwegian Shipowners’ Mutual War Risks Insurance Association, may have noticed a lot of boat-building material, such as fiberglass; the glass fibers resist vaporization. A limpet mine would leave very little alien material, as it is a small charge in a simple package that gains destructive power from intimate contact with the hull.

The choice of attribution is puzzling: “Iran’s elite Revolutionary Guards (IRGC) are “highly likely” to have facilitated…” as  opposed to “IRGC are likely to be responsible…”

Iran has provided the Houthis with weapons of this kind. But the eastern border of Yemen, which is starkly empty of habitation, is 1600 miles by sea from Fujairah. The nearest port, Al Mukalia, is 2160 miles, but it’s under UAE control.

The Houthis don’t need a port to mount the attacks. They could have shoved off from a beach, and  slowly motored their way 1600 miles. But the choice to label the IRGC as the enabler, as opposed to the attacker, appears to be an unsupported complication.

Factoring in the Houthis may be supported by other intelligence that cannot be revealed.  But some technical collections may be circumvented by Iranian fall-backs to primitive forms of communication, and use of deception games.

The sophistication of Iran  implies that a complex deception game, artificially involving Houthis, cannot be ruled out.



U.S. Hypersonic Strategies Part 3

You played the board game, which demonstrated an odd fact. By making random sideways movements, the red checker “evaded”  your black checker, which you attempted to guide with your purposeful hand. How could the brainless strategy of the red checker outwit your intelligent black checker?

There will be no math in this post, which continues to emphasize accessibility to the audience. It must remain rough, since the performance figures for Russian and Chinese hypersonic vehicles are not available to open source.  I’m hesitant to introduce the concepts of kinetic and potential energy. There are some interesting twists that go a little beyond freshman physics.

The game imitates the situation of the First Gulf War, when Patriot PAC-2 missiles failed to intercept — or failed to destroy, Iraqi Scud missiles that spontaneously disintegrated into pieces, tumbling through the atmosphere in complex paths. It was  noticed that  interception and destruction are practical distinctions, with much damage caused by still-incendiary boosters landing on soft targets, even if the warheads did not detonate.

The above is offered partly as a lesson in confusion. It includes issues that are barely related to intercepting hypersonic vehicles. Confusion typifies the subject, because missile defense is not one problem. It consists of at least four problem-regimes, some separated by mere seconds, as the aggressor missile transitions from one regime to the next. Each requires a different counter-weapon. These regimes were understood to be constants of the problem, because in the formative period of ABM theory,  only two kinds of missiles were subject to strategic consideration: ballistic, and cruise. The ability of subsonic cruise missiles to evade, even in the current day, could have been a show-stopper, but imagination has no limits. Hence, Star Wars.

The problem  was based on a missile that is thrown like a stone. After a few minutes of powered flight, the missile is going about 15000 miles/hour, arching over the atmosphere with no opportunity to change direction. Above the atmosphere, the warhead separates from the booster, and proceeds like a thrown stone to the target.  At the cost of some additional weight and complexity, the simple warhead can be replaced by a steerable “bus”, which makes modest adjustments in speed and direction to drop off its passengers, MIRVs, (multiple independently targetable reentry vehicles).

Each MIRV is a thin cone, designed to withstand the incredible heat of reentry, with small rockets, “thrusters”, to keep the pointy end forward.  In fact, a MIRV vehicle could be steered a little when it descends far enough into the atmosphere, but it wasn’t thought worthwhile, as it would add weight. As early as 1963, a  U.S.  experiment with a surplus Thor warhead showed that steering is quite feasible.

The ability of a reentry vehicle to convert forward speed into sideways movement is critical to the problem. When the MIRVs, or MIRVs attached to the bus, are above the atmosphere, they proceed like stones. When they enter the upper atmosphere, the path becomes a little complicated. This is why it’s preferable to intercept a warhead in the vacuum of space.

You may note with pride that the ancestral hypersonic vehicle, the source of current frustration, was an American innovation, the Pershing II. It was designed to fly low, in a “flat trajectory”, with a single programmed “jink” as it entered the atmosphere.  Modern hypersonic vehicles greatly extend this idea, replacing predictable flight with the unpredictable.

The  problem of ballistic flight resembles the bull and the matador. The bull has more energy, the matador has more agility. The matador dodges the bull, whereas the interceptor gets in front of the bull, but otherwise, the analogy is strong. But what if the bull has the agility of the matador, as well as its speed?

The buzzword “hypersonic” is a detour to understanding. Speed is an issue in some cases, such as anti-ship, but a hypersonic missile  is slower than an ICBM. To note that a hypersonic missile “flies through the atmosphere” doesn’t quite nail it. So let’s nail.

The antimissile, as it exists today, launches a payload, the Exoatmospheric Kill Vehicle.  The EKV does not “fly in air” With very small, precise rockets, it places itself with extreme precision in the path of the red checker. Like  the matador, the EKV has no forward energy of its own, but  agility of lateral movement. In the vacuum of space, the MIRV “red checker” proceeds unalterably to its doom.

A strategic hypersonic warhead/missile has energy of forward motion. Flying  in the atmosphere, it is designed to have “lift”.  By banking, it converts a significant part of forward energy into sideways motion.  An airplane does this more efficiently, but the hypersonic missile is going very fast, so it has much more to start with. This forward energy is like a “battery” that the missile can drain to make changes in direction. It obtains a large initial velocity from a  booster stage. The Russian Avangard has an integral scramjet that allows it to exceed the performance of the Tsiolkovsky rocket equation.

The rocket equation is cruel to the EKV.  Take a look at a picture of one of the EKV designs. There are other pictures around the web you may wish to examine. The weight of the EKV is variously stated to be 120 or 140 pounds. It appears to have two propellant tanks  and two oxidizer tanks. The amount is not critical to the argument, so assume  50 pounds total, of which 15 is propellant.  This is not a lot of energy; it’s much less than a car tank of gas. It can’t match the amount of forward energy the adversary can convert into sideways motion.

As originally conceived, it didn’t have to. The EKV has a very high forward velocity/energy, provided by the Ground Based Interceptor. But it cannot convert any of that forward energy into lateral movement. It is specialized to operate in space, and is protected by a shroud until it gets there. Lateral movement must come from the amount of fuel you could fit in a Jerry can. And unlike the Avangard ramjet, it cannot escape the rocket equation.

Takeaway: The bright child of U.S. antimissile efforts, and hypersonic adversary missiles, are so different, never the twain shall meet.

Next: Conceptual Thinking.