The THOR system is composed of a thousand or more cheap satellites

Sunday, February 17th, 2019

If you drop something dense and aerodynamic from high enough up, it will hit the ground really, really hard — maybe hard enough to qualify as a kinetic bombardment weapon:

During the Vietnam War, the US used what it called “Lazy Dog” bombs. These were simply solid-steel pieces, less than 2 inches long, fitted with fins.

There was no explosive: They were simply dropped by the hundreds from planes flying above Vietnam.

Lazy Dog projectiles (aka “kinetic bombardment”) could reach speeds of up to 500 mph as they fell to the ground and could penetrate 9 inches of concrete after being dropped from as little as 3,000 feet.

If you drop a telephone pole-sized (20′×1′) tungsten cylinder from orbit, the 9-ton “rod from God” should hit at Mach 10, with the kinetic energy equivalent to 11.5 tons of TNT (or 7.2 tons of dynamite).

Robin Hanson recently mentioned such “rods from God,” and I just happened to be reading There Will Be War, which includes Jerry Pournelle’s “original” 1981 description of Project THOR, which describes something subtly different — a barrage of 20-pound projectiles made of tungsten, less than an inch in diameter and three or four feet long, traveling at Mach 23:

One of the most difficult security missions which the United States must accomplish is the protection of our interests around the globe. Incidents like the North Korean seizure of the USS Pueblo have demonstrated our weakness in not being able to respond quickly and authoritatively in remote locations. Our only solution to this problem so far has been the naval carrier task force. Carrier-based aircraft can project military force to protect our citizens and allies in remote regions of the world. Unfortunately, the high cost and vulnerability of nuclear carriers and their required aircraft and support fleets make them an unattractive solution.

[...]

To balance the force of gravity, a satellite two hundred miles above the surface must travel at a speed of seventeen thousand five hundred miles per hour. At this speed, the satellite travels around the Earth once every ninety minutes. With a hundred satellites in orbits near this altitude and traveling in random orbital inclinations, one of the satellites will pass over any given location on Earth every thirty minutes. With a thousand satellites, the timing between satellites overhead is less than ten minutes. The basic physics of orbital motion gives us our global coverage; it also gives us the weapon. The extremely high velocity of a satellite in orbit gives it a tremendous amount of kinetic energy. If a one pound object moving at orbital velocity ran into a stationary target, the energy released in the impact will be the equivalent of exploding almost ten pounds of TNT.

[...]

The THOR system is composed of a thousand or more cheap satellites, each made up of a bundle of projectiles, guidance and communications electronics, and a simple rocket engine.

[...]

The result is spectacular: a bundle of tens or hundreds of twenty pound projectiles streak down at four miles per second to strike targets with the explosive equivalent of two hundred pound bombs each.

[...]

Even if an enemy were to detonate one or more nuclear devices in space in an attempt to destroy THOR, there are a thousand or more widely scattered satellites he must destroy. Because the satellites are at different altitudes and have different orbital inclinations, any holes produced in the global coverage by a nuclear explosion are filled in after several hours by the orbital motions of the satellites.

[...]

The satellite can be cocooned in foam, which would be difficult to detect with radar anyway and could be shaped to make detection even more difficult (stealth satellites!).

[...]

The foam would insulate the satellite against the heat and shock of nuclear explosions or laser beams.

[...]

The jet of metal particles produced when a shaped charge warhead detonates is traveling at about the same velocity as a THOR projectile when striking a target.

[...]

The jet of metal from the TOW warhead weighs only a fraction of an ounce; a THOR projectile weighs over twenty pounds!

[...]

If the projectile were composed of an outer shell with sand-sized particles inside, it could be designed to explode and disperse the particles just before impact. The metal particles would instantly vaporize, with the resulting shock wave flattening troops, aircraft, or other targets much like the fuel-air explosive bombs presently in service.

[...]

The advantages of the THOR weapon system are its low cost, global coverage, quick reaction time, and survivability.

[...]

To de-orbit the projectiles and bring them down at an angle of thirty degrees from vertical requires almost as much energy as was required to orbit the projectiles initially, and requires a large quantity of propellant for each THOR satellite.

[...]

The individual THOR satellites are most vulnerable while the de-orbit propulsion burn is taking place, when a rocket exhaust plume is a bright beacon marking the location of the satellite for possible destruction by enemy laser weapon satellites. Two solutions are a cold gas propulsion system (high weight of propellant required) or a very fast propulsion impulse which ends before the laser weapon could be brought to bear on the THOR satellite.

[...]

With the Global Positioning System navigation satellite network in operation, each satellite could passively receive its own location in space to a very high accuracy while doing nothing to reveal its own position.

[...]

Communication by laser beams, which are extremely narrow and almost impossible to intercept, may be possible if the position of each of the thousand or more THOR satellites can be calculated accurately enough to hit the desired satellite.

[...]

The projectile could be protected by an ablative nose tip which would vaporize and carry off the heat from atmospheric friction during the few seconds of atmospheric passage.

[...]

The high speed of the projectile through the atmosphere near the ground where the density of the air is highest would produce a luminous bow shock wave directly in front of the missile. Penetrating such a layer might be a problem, but high frequency radio waves, infrared light, visible light, or ultraviolet light might be effective for targeting. A visible light sensor might have a window covered with a filter which passes light of a wavelength which is not emitted by the ionized air in the shockwave.

The real point of the system, as he points out, is that it could quickly (and cheaply) hit any target, anywhere on earth — which seemed really, really useful, a few months later, when HMS Sheffield succumbed to a French-made Exocet missile in the Falklands. Of course, getting tungsten rods up into space is only economical once you have frequent launches of your newfangled space shuttle.

The Air Force forgot what business it was in

Sunday, February 3rd, 2019

The United States Air Force has lost its way, Jerry Hendrix argues — and most of its bombers, too:

It has forgotten what business it’s in, mistakenly believing that its raison d’être is air supremacy while forgetting that the core of its mission is long-range strike. If the nation is to be successful in the great-power competition it finds itself in, the Air Force will need to find its way home and regain its strategic relevance in an environment dominated by anti-access/area-denial systems employed by China and Russia.

[...]

The Air Force once understood its purpose with stark clarity. In the first half of the 20th century, air-power advocates continually stressed the importance of bypassing tactical skirmishes and penetrating to the enemy’s vital centers to coerce either the foreign government or its population to submit. Independent air forces in Great Britain and Italy focused their procurement efforts on larger and longer-range heavy bombers. Non-independent air forces, such as the U.S. Army Air Corps, sought the same even as their parent service (the U.S. Army, in the American case) pressed them to buy tactical aircraft and perform direct-combat air-support missions for ground infantry and armor units. This made some sense during World War II, when long-range bombers found themselves in need of fighter escorts to fend off enemy fighters and establish temporary air dominance for the bombers to get through to their targets. But after the war, science and engineering combined to alter circumstances.

The jet engines that came to dominate aircraft design during the early years of the Cold War changed the nature of force employment, as jet fighters no longer had the range to escort the jet bombers of the newly established and very powerful Strategic Air Command to targets inside the Soviet Union. Fighters then became specialized for air-defense and air-dominance missions within a radius of a couple of hundred miles of fighter bases. Strategic Air Command bombers, which numbered in the thousands, soon began to specialize themselves, evolving towards designs that could fly higher and faster in order to penetrate Soviet air defenses. The Soviets responded by building new surface-to-air missiles and high-altitude/high-speed interceptors to rob American bombers of their advantages. It was only at the end of the Cold War, with the introduction of the stealth B-2 Spirit bomber, that bombers regained the upper hand in the U.S.–USSR strategic competition. But by then, the Strategic Air Command had been disestablished, and the Air Force felt that its mission had changed.

The change began during the Vietnam War, in which fighters flying from land bases in South Vietnam were loaded up with bombs to hit land targets in North Vietnam and along supply routes in neighboring countries. The improved accuracy of smaller aircraft carrying lighter loads of bombs and providing combat air support to American ground forces in direct contact with the enemy began to subtly alter the internal culture of the Air Force. The bomber “tribe,” based in the politically powerful Strategic Air Command, had supplied six of the first ten Air Force chiefs of staff, but it began to lose influence within the service to the fighter “tribe.” In the 36 years since Chief of Staff Lew Allen Jr. retired, no bomber pilot has occupied that office, and the Air Force’s inventory of bombers has shrunk from over 10,000 aircraft during the 1950s to fewer than 200 today. Fighter pilots gained ascendency based upon the assumptions of access to bases within range of their enemies, the ability of their supporting tanker force to survive, and the greater importance of air supremacy than long-range-strike capability.

Air supremacy is a straightforward concept. It seeks a degree of superiority over an opposing air force such that the enemy is incapable of effective interference with friendly aircraft or ground and naval forces. This definition of air superiority held for regional wars such as those in Vietnam, the former Yugoslavia, Iraq (both times), and Afghanistan (where the enemy had no opposing air power to speak of). Air Force theorists also state that air superiority applies to theater campaigns (those that range across an entire region of the globe), enabling larger aircraft, cargo haulers, refueling tankers, and bombers to operate freely — except when they cannot, and that is where the modern United States Air Force lost its way.

Air supremacy is all about fighting a long war. It assumes proximity of air-power units to the front lines and/or to the adversary’s coast. It also assumes that the U.S. will fight the next war the way it has fought small wars over the 70-plus years since the end of World War II — deploying combat and support forces from the United States; gradually building up forces and supplies in theater; “rolling back” adversary defenses to gain air, sea, and ground control; and decisively defeating the adversary’s military in force-on-force engagements. All these assumptions are wrong.

Both China and Russia have noted how effectively the United States has fought its wars over the past 50 years and have invested in a new series of sensors and weapons that seek to push American forces back from their shores. Broadly grouped under the label of “anti-access/area-denial” systems, these radars, satellites, cruise missiles, ballistic missiles, and submarines all seek to ensure that U.S. power-projection forces cannot reach their vital political, economic, and military centers. Because of these investments, most of America’s most recent weapons systems, including all three variants of the new F-35 multi-role fighter, will be unable to reach Chinese or Russian targets. There will be no proximity to “front lines” — not that it matters, as there will be no front lines. The next battlefield will be fluid and spread out over vast areas. Moreover, both legacy fighters and just-fielding F-35s are already vulnerable to modern integrated air- and missile-defense networks. The enemies get a vote, and they have cast it.

[...]

When World War II ended, the Army Air Forces understood these lessons, and when the U.S. Air Force was established in 1947 and the Strategic Air Command thereafter, the long-range bomber and the long-range strike mission lay at the center of their culture. But then regional wars and the end of the Cold War happened, and the Air Force forgot what business it was in. It got into short-range fighters and fought small, short-range wars.

He’s a big fan of the B-21 Raider.

He regularly asks students to throw spears at him

Monday, January 28th, 2019

Anthropologists have long concluded that Neanderthals used their thick, heavy spears only at close range, because the academics could only throw those spears about 10 meters. What happens when athletes throw Neanderthal spears?

On a very cold January morning, in an athletic field in central England, Annemieke Milks watched as six javelin-throwers hurled a pair of wooden spears. Their target was a hay bale, “meant to approximate the kill zone of a large animal like a horse,” says Milks, an archeologist at University College London. And their spears were replicas of the oldest complete hunting weapons ever found — a set of 300,000-year-old, six-and-half-foot sticks found in a mine at Schöningen, Germany.

The athletes managed to throw their replicas over distances of 65 feet. That’s a far cry from modern javelin feats — the world record for men, set in 1996, is 323.1 feet. But it’s twice what many scientists thought that primitive spears were capable of. It suggests that, contrary to popular belief, early spear-makers — Neanderthals, or perhaps other ancient species like Homo heidelbergensis — could probably have hunted their prey from afar.

[...]

“The 10-meter distance was repeated over and over again, but not backed up with much evidence.” It came from an influential ethnographic review that considered the spear-throwing skills of many modern populations, but didn’t include adept groups like the Tasmanian and Tiwi peoples of Australia. And it was bolstered by studies and anecdotal reports in which spears were thrown by anthropologists—hardly a decent stand-in for a skilled Neanderthal hunter.

For example, John Shea, an archeologist at Stony Brook University tells me that he regularly takes his students into an athletic field and asks them to throw replica Schöningen spears at him. “If they hit me, I pledge to give them $20,” he says. “I’ve been doing this ‘experiment’ for 25 years and I’ve neither got so much as a scratch on me nor parted with any cash. The spears come sailing in so low and slow I can usually just step sideways out of the way, bat them away with a stick or, if I am feeling really cocky, catch them in mid-air.”

A German sport scientist and javelin-thrower named Hermann Rieder had more success: In a small study, he managed to hit targets from around 16 feet away and suggested that the spears were useful weapons at longer distances.

[...]

It’s sometimes said that heavy spears would slow mid-flight and hit their targets with dull thuds. But Milks found that the replicas slowed very little, and landed with a kinetic wallop comparable to projectiles launched by bows or spear-throwing tools.

But Steve Churchill, an anthropologist from Duke University, notes that the javelin-throwers only hit their target a quarter of the time, and less so at the furthest distances. He’s also unclear as to how many of those “hits” would have been strong enough to, say, penetrate an animal’s hide. In his own experience (and he freely admits that he’s not a trained thrower), Schöningen replicas wobble a lot and tend to strike targets at glancing angles. They might fly far, in other words, but do they fly true? “This is a very good study,” he says, but “I don’t see a lot here to convince me that the Schöningen spears were effective long range weapons.”

Milks counters that professional javelin-throwers go for distance, and aren’t trained to hit targets. Despite that, some of them clearly got the sense that the heavy spears behave unusually, vibrating along their axis and flexing on impact. The more experienced athletes compensated for this by putting spin on the spears. “That brought home how important it is to use skilled throwers,” Milks says. “What I really want to do now is to go to hunter-forager groups and have them show us these spears are capable of. They use spears from age 6, which is something I can’t replicate with javelin athletes.”

Decoupling is not a worry for anything but a very small explosion

Thursday, January 17th, 2019

The U.S. government conducted more than 1,000 nuclear tests, most of them in the Nevada desert or on faraway Pacific islands, but it also set off a couple nukes under Mississippi:

In 1959, the American physicist Albert Latter theorized that setting off a bomb in an underground cavity could muffle the blast. After tests with conventional explosives, Latter wrote that a detonation as big as 100 kilotons—more than six times bigger than the bomb dropped on Hiroshima—“would make a seismic signal so weak it would not even be detected by the Geneva system.” His theory, known as “decoupling,” became a rallying point for people who wanted to keep testing, says Jeffrey Lewis, of the James Martin Center for Nonproliferation Studies in Monterey, California.

“They wanted to come up with a reason that we couldn’t verify an agreement with the Soviets,” says Lewis, who’s also the publisher of the Arms Control Wonk blog. But in 1963, after the Cuban Missile Crisis brought the world nose-to-nose with the unthinkable, the superpowers signed the Limited Test Ban Treaty. It kept future tests underground, and researchers turned to making sure those tests would be spotted.

The Atomic Energy Commission wanted to test Latter’s theory using actual nukes. And salt deposits were considered the ideal places for tests, since they could be excavated more easily than rock and the resulting cavity would endure for years. So the search was on for a salt dome in territory similar to where the Russians tested their bombs, Auburn University historian David Allen Burke says.

“It had to be a certain diameter. It had to be a certain size. It needed to be a very large salt dome that was still a distance underground and not where it could interfere with water or petroleum or anything else,” says Burke, who wrote a book about the Mississippi tests.

That led the agency to southern Mississippi, which is full of salt domes. The government leased a nearly 1,500-acre patch of forest atop one of those domes and got to work.

[...]

The first blast, code-named Salmon, was a 5.3-kiloton device that would blow a cavity into the salt dome half a mile underground. The second, Sterling, was only 380 tons, and would go off in the cavity left behind by Salmon. AEC crews drilled a 2,700-foot hole down into the salt dome, lowered the first bomb into it, plugged it with 600 feet of concrete… and waited.

The Salmon test was put off nearly a month by a string of technical problems and bad weather, including Hurricane Hilda, which hit one state over in Louisiana. People living up to five miles from the test site were evacuated and recalled twice in preparation for blasts that never happened. They got paid $10 a head for adults and $5 for children for their trouble.

[...]

Far from Latter’s predictions that a blast as big as 100 kilotons could be kept off the scopes, Lewis says, it turned out that decoupling “is not a worry for anything but a very small explosion.” However, the data helped shape a later treaty which limited underground tests to 150 kilotons.

[...]

Federal records now indicate cancer rates in Lamar County are lower than both the state and national average.

(Hat tip to Hans Schantz.)

For the black market, everything stays the same

Saturday, January 12th, 2019

Gun ownership is rising across Europe, the Wall Street Journal reports:

The uptick was spurred in part by insecurity arising from terrorist attacks—many with firearms, and reflects government efforts to get illegal guns registered by offering amnesty to owners.

Europe is still far from facing the gun prevalence and violence in Latin America or the U.S., which lead the world. World-wide civilian ownership of firearms rose 32% in the decade through 2017, to 857.3 million guns, according to the Small Arms Survey, a research project in Geneva. Europe accounts for less than 10% of the total.

But Europe’s shift has been rapid, and notable in part because of strict national restrictions. In most European countries, gun permits require thorough background checks, monitored shooting practice and tests on regulations. In Belgium, France and Germany, most registered guns may only be used at shooting ranges. Permits to bear arms outside of shooting ranges are extremely difficult to obtain.

Strict registration requirements don’t account for—and may exacerbate—a surge in illegal weapons across the continent, experts say.

Europe’s unregistered weapons outnumbered legal ones in 2017, 44.5 million to 34.2 million, according to the Small Arms Survey. Many illegal weapons come from one-time war zones, such as countries of the former Yugoslavia, and others are purchased online, including from vendors in the U.S.

[...]

Armed robbery and similar crimes often entail illicit guns, while legally registered firearms tend to appear in suicide and domestic-violence statistics, said Nils Duquet of the Flemish Peace Institute, a Belgian research center.

“It’s clear that illegal guns are used mostly by criminals,” he said.

[...]

In Germany, the number of legally registered weapons rose roughly 10%, to 6.1 million, in the five years through 2017, the most recent year for which statistics are available, according to Germany’s National Weapons Registry. Permits to bear arms outside of shooting ranges more than tripled to 9,285, over the same five years.

Permits for less lethal air-powered guns that resemble real guns and shoot tear gas or loud blanks to scare away potential attackers roughly doubled in the three years through the end of 2017, to 557,560, according to the registry.

[...]

In Belgium, firearm permits and membership in sport-shooting clubs has risen over the past three years.

Belgian applications for shooting licenses almost doubled after the terrorist attacks by an Islamic State cell in Paris in Nov. 2015 and four months later in Brussels, offering “a clear indication of why people acquired them,” said Mr. Duquet.

[...]

Belgium has for years tightened regulations in response to gun violence, such as a 2006 killing spree by an 18-year-old who legally acquired a rifle.

“Before 2006, you could buy rifles simply by showing your ID,” recalled Sébastien de Thomaz, who owns two shooting ranges in Brussels and previously worked in a gun store.

“They used to let me shoot with all my stepfather’s guns whenever I joined him at the range,” said Lionel Pennings, a Belgian artist who joins his stepfather at one of Mr. De Thomaz’s shooting ranges on Sundays.

Mr. Pennings recalled that in the past he could easily fire a few rounds with his stepfather’s gun. “Now it’s much stricter,” he said. “You can only use the guns you have a permit for.”

A Belgian would-be gun owner must pass almost a year of shooting and theory tests, plus psychological checks, said Mr. De Thomaz.

The gun-range owner questions the impact of that policy. “With each terror attack, the legislation gets stricter,” he said. “For the black market, everything stays the same.”

Quickly fire barbed Kevlar cords toward suspects at speeds of 640 feet per second

Sunday, October 21st, 2018

The NYPD is testing a high-powered lasso gun to subdue mentally ill suspects:

Unveiled last year, the BolaWrap™ 100 is a hand-held remote that allows officers to quickly fire barbed Kevlar cords toward suspects at speeds of 640 feet per second. The stated goal of the product is to entangle a person’s limbs “early in an engagement,” thereby allowing police officers to avoid using lethal force. The intended target is described by the company as “the mentally ill population” and, elsewhere, “the bad guys.” Each unit costs $800, and sounds like a gunshot when discharged.

[...]

Wired Technologies, which manufactures and distributes the wraps, claims that 24 police departments across the country are testing the product internally, and that six departments are testing it in the field. A version that sounds less like a gunshot is currently in development, for use on college campuses, according to Mike Rothans, the senior vice president of Wrap Technologies.

During Thursday’s demonstration, Adams, flanked by Rothans and Wired Technologies CEO David Norris, assured reporters that the product was neither painful nor dangerous (Adams did wear protective goggles, just in case). The trio brushed off questions about whether it might be more difficult to deploy the wraps in a crowded, high-pressure environment, rather than a tightly controlled courtroom, by pointing to the device’s laser sight. Despite the fact that a website advertises the wraps as having 380 pounds of strength, Rothans promised that they wouldn’t be strong enough to strangle someone if accidentally fired at their neck.

Rather, the gizmo should be seen as a low-risk alternative to the more painful, less reliable stun gun, they said. At one point, Adams referred to a video—shown by company reps earlier in the demonstration—of an 86-year-old man with dementia getting tased by police officers during a traffic stop, as precisely the sort of situation in which the resistance tool could be of use. “Some might look at the incident with the 86-year-old and say why would you need any force there, but that’s not the real universe of policing,” said Adams, a former NYPD officer. “I would have used the device with the 86-year-old. Maybe I strike his legs instead of his arms, so he can break his fall.”

In Adams’s estimation, the device could successfully subdue about 70 percent of the 150,000 or so emotionally disturbed individuals encountered annually by the NYPD. The department’s handling of such cases—known as EDPs—has attracted scrutiny in recent years, with advocates demanding better training for officers responding to mental health crises, particularly following the deaths of Saheed Vassell and Deborah Danner.

The article refers to “Wired Technologies,” but I believe the company name is Wrap Technologies:

Missile lock-on!

Friday, August 31st, 2018

I was listening to the audio version of David Suarez’s techno-thriller Kill Decision, when the pilot of the good guys’ C-130 announced “missile lock-on!” How exactly does missile lock-on work, and how does the target know it’s locked on?

Aircraft radars typically have two modes: search and track. In search mode, the radar sweeps a radio beam across the sky in a zig-zag pattern. When the radio beam is reflected by a target aircraft, an indication is shown on the radar display. In search mode, no single aircraft is being tracked, but the pilot can usually tell generally what a particular radar return is doing because with each successive sweep, the radar return moves slightly.

[...]

In track mode, the radar focuses its energy on a particular target. Because the radar is actually tracking a target, and not just displaying bricks when it gets a reflection back, it can tell the pilot a lot more about the target.

[...]

An important thing to note is that a radar lock is not always required to launch weapons at a target. For guns kills, if the aircraft has a radar lock on a target, it can accurately gauge range to the target, and provide the pilot with the appropriate corrections for lead and gravity drop, to get an accurate guns kill. Without the radar, the pilot simply has to rely on his or her own judgement.

[...]

And what about missiles? Again, a radar lock is not required. For heat-seeking missiles, a radar lock is only used to train the seeker head onto the target. Without a radar lock, the seeker head scans the sky looking for “bright” (hot) objects, and when it finds one, it plays a distinctive whining tone to the pilot. The pilot does not need radar in this case, he just needs to maneuver his aircraft until he has “good tone,” and then fire the missile. The radar only makes this process faster.

Now, radar-guided missiles come in two varieties: passive and active. Passive radar missiles do require a radar lock, because these missiles use the aircraft’s reflected radar energy to track the target.

Active radar missiles however have their own onboard radar, which locks and tracks a target. But this radar is on a one-way trip, so it’s considerably less expensive (and less powerful) than the aircraft’s radar. So, these missiles normally get some guidance help from the launching aircraft until they fly close enough to the target where they can turn on their own radar and “go active.” (This allows the launching aircraft to turn away and defend itself.) It is possible to fire an active radar missile with no radar lock (so-called “maddog”); in this case, the missile will fly until it’s nearly out of fuel, and then it will turn on its radar and pursue the first target it sees. This is not a recommended strategy if there are friendly aircraft in close proximity to the enemy.

[...]

Radar is just radio waves, and just as your FM radio converts radio waves into sound, so can an aircraft analyze incoming radio signals to figure out who’s doing what. This is called an RWR, or radar warning receiver, and has both a video and audio component.

[...]

Each time a new radar signal is detected, it is converted into an audio wave and played for the pilot. Because different radars “sound” different, pilots learn to recognize different airborne or surface threats by their distinctive tones. The sound is also an important cue to tell the pilot what the radar is doing: If the sound plays once, or intermittently, it means the radar is only painting our aircraft (in search mode). If a sound plays continuously, the radar has locked onto our aircraft and is in track mode, and thus the pilot’s immediate attention is demanded. In some cases, the RWR can tell if the radar is in launch mode (sending radar data to a passive radar-guided missile), or if the radar is that of an active radar-guided missile. In either of these cases, a distinctive missile launch tone is played and the pilot is advised to immediately act to counter the threat. Note that the RWR has no way of knowing if a heat-seeking missile is on its way to our aircraft.

When a flash-bang grenade isn’t enough

Saturday, July 21st, 2018

Flash-bang grenades are great, but what if you want to deliver 14 flash-bang grenades from 1,000 meters away?

“Currently the armed forces are unable to deliver non-lethal effects at extended ranges,” Michael Markowitch, an engineer involved in designing the munition, said in an Army press release in 2016. “Our goal was to develop a mortar that would be capable of delivering a non-lethal payload at ranges typical of mortar systems.”

“We took our inspiration for our design from the family of illumination mortars. They use parachutes attached to an illumination candle to slow its descent and illuminate an area. The team determined that similar designs could be used to control the descent of the metal parts,” Markowitch added.

This first field-test occurred during this year’s Rim of the Pacific exercise, which occurs every two years and involves more than 20 nations and dozens of warships.

The modified round is compatible with existing 81 mm mortar tubes and flies through the air like a standard mortar. The round’s effective range is between 450 and 1,500 meters.

When the round is roughly 250 meters above the target, a time-delay fuse detonates. The mortar’s nose and tail sections separate and the 14 nonlethal cardboard-encased submunitions are released.

Parachutes also release from the mortar’s nose and tail, and the mortar floats to the ground while the flash-bang grenades fall, stabilized by drag ribbons.

The nonlethal cartridges are designed to detonate simultaneously, covering an area of roughly 30 meters. Each cartridge, like the M84 stun grenade, emits a roughly 180-decibel bang and a flash of more than one million candela within five feet of the initiation spot.

Flash-Bang Mortar Dispersion

Developers of the system have also shown interest in adding infrared or ultraviolet ink to the mortar in order to paint anyone near the detonation. This could help soldiers identify people in a crowd who may disperse from the impact site, according to the Defense Department release.

The Spanish conquistador helmet wasn’t worn by Cortez or Pizarro

Tuesday, May 15th, 2018

Someone mentioned “Spanish conquistador helmets” on Twitter, and I helpfully added that the iconic helmet is known as a morion. What I didn’t realize is that the Spanish conquistador helmet wasn’t worn by the Spanish conquistadors we’ve all heard of:

The iconic morion, though popularly identified with early Spanish explorers and conquistadors, was not in use as early as the conquest of Mexico by Hernan Cortez or Francisco Pizarro’s conquest of the Incas in South America. Thirty to forty years later, it was widely used by the Spanish, but also common among foot soldiers of many European nationalities, including the English; the first English morions were issued during the reign of Edward VI. Low production costs aided its popularity and dissemination although officers and elite guards would have theirs elaborately engraved to display their wealth and status.

The crest or comb on the top of the helmet was designed to strengthen it. Later versions also had cheek guards and even removable faceplates to protect the soldier from sword cuts.

Spanish Conquistador Morion

The morion’s shape is derived from that of an older helmet, the Chapel de Fer, or “Kettle Hat.” Other sources suggest it was based on Moorish armor and its name is derived from Moro, the Spanish word for Moor. The New Oxford American Dictionary, however, derives it from Spanish morrión, from morro ’round object’. The Dictionary of the Spanish Language published by the Royal Spanish Academy indicates that the Spanish term for the helmet, morrión, derives from the noun morra, which means “the upper part of the head”.

In England this helmet (also known as the pikeman’s pot) is associated with the New Model Army, one of the first professional militaries. It was worn by pikemen, together with a breastplate and buff coat as they stood in phalanx-like pike and shot formations, protecting the flanks of the unarmored musketeers.

Having a short barrel doesn’t mean the pattern will be huge

Monday, May 7th, 2018

Since we were just discussing the maximum effective range of buckshot, Greg Ellifritz’s latest post, on buckshot patterning in a short-barreled shotgun, caught my attention:

I recently got my Federal paperwork back from the creation of a short-barreled shotgun. I have an old HK Benelli M-1 that I equipped with a 14″ barrel and SureFire forend. I took it out to shoot it last weekend for the first time.

With such a really short barrel, you would expect a huge pattern, right? Wrong.

Pattern is more a function of the type of choke the shotgun has than its barrel length. In fact, using buckshot loads that are not buffered or encased in a shot cup, patterns will get LARGER as the barrel length increases. The longer the barrel, the more likely that the pellets hit the inside of the barrel or each other while traveling down the barrel of the gun. Those strikes deform the each of the pellets and cause them to fly erratically, leading to a larger overall spread. Having a short barrel doesn’t mean the pattern will be huge.

Another factor of patterning size is the manufacturer of the ammunition. Not all 00 buckshot is equal. Rounds with a specialized shot cup (Federal Flight Control, Hornady TAP/Critical Defense) will shoot the tightest pattern. “Buffered” buckshot will shoot larger patterns. Unbuffered buckshot will create the largest pattern. In general, the cheaper the round, the larger and more inconsistent the pattern.

For an idea about this variability, take a look at the target below. I shot four different types of 00 Buck through the 14″ Benelli at a distance of 30 feet. There was a tremendous variation.

Buckshot Patterns from 14-Inch Cylinder Bore at 30 Feet

  • The Remington 00 Buck shot a pattern about 10″ in diameter
  • The Speer Low Recoil 00 Buck shot a pattern about 6″ in diameter
  • The Federal 00 Buck shot a pattern about 7″ in diameter
  • The Hornady TAP Magnum 00 Buck shot a pattern less than 3″ in diameter.

There is also a myth that 00 Buckshot spreads approximately one inch per yard of travel. This may be close to true with very cheap buckshot fired out of a cylinder bore. Shotguns that have a choke or rounds that use a specialty shot cup shoot groups much tighter than this standard formula suggests.

Maximum Effective Range of Buckshot

Saturday, April 28th, 2018

Watching an old police-training film, Shotgun or Sidearm?, raised some questions about shotgun patterns, and commenter ASM826, who co-blogs with Borepatch, emphasized the importance of modern pattern-controlled shells.

Brass Fetcher Ballistics tested 12 gauge shotshells — using #4, #1 and 00 buckshot (both plated and unplated) — to determine the maximum effective range of each type of shotshell when shot through a practical 12 gauge shotgun with cylinder choke.

Maximum effective range is defined here as:

  1. Having a hit probability greater than chance (greater than 50% of pellets make scoreable hits on target).
  2. Buckshot traveling fast enough to make incapacitating hit at this range (12.0” or deeper penetration in nominal 10% ballistic gelatin).

They immediately found that unplated #4 buckshot won’t reliably penetrate 12 inches of ballistic gelatin, so it is not acceptable for self-defense at any range. Plated #4 buckshot only penetrates 12 inches of ballistic gelatin out to 11 yards, so it’s not much better.

Bucketshot Velocity vs. Distance
Buckshot Velocity and Penetration
Unplated #1 buckshot penetrates 12 inches of ballistic gelatin out to 29 yards, while plated #1 is effective out to 51 yards.

At this distance, keeping most of the pellets on the target becomes an issue, as they found in their testing:

Distances between muzzle and target for the #4 buckshot and unplated #1 buckshot correspond to the maximum distance at which a single shot pellet is expected to be traveling fast enough to score an incapacitating hit. The remaining shotshells were shot at 40 yards distance.

Buckshot Hit Percentage
Buckshot Maximum Effective Range

It will be noted from above that the physical distance between the muzzle of the test shotgun and the paper targets was 40 yards for the #1 buckshot (plated, pattern-controlled), 00 buckshot (unplated, buffered) and 00 buckshot (plated, pattern-controlled.) This was to ensure that all shot pellets struck the paper and could be accounted for in the further range calculation. The 00 buckshot (unplated, buffered) load impacted the targets with greater than 50% of the shot pellets at least 50% of the time. The #1 buckshot (plated, pattern-controlled) load had a higher hit probability than the unplated 00 buckshot (maintaining a hit probability of 50+% out to 57 yards) but the individual pellets lacked the mass and initial velocity to retain terminal effectiveness beyond 51 yards. As such, the maximum effective range of this load was determined to be 51 yards. The 00 buckshot (plated, pattern-controlled) load maintains a hit probability of 50+% out to 52 yards, which is the limiting factor in maximum effective range because the individual pellets are sufficiently massive and have a high enough velocity to retain terminal effectiveness to a distance of 104 yards.

Determination of hit probability (past the 40 yard distance that was physically tested at) was based upon the average mean radius of the tested 10 shotshell/10 target test groups. Mean radius is defined as the average of the straight line distances between the Center-of-Shot-Group and each shot (USARIEM TECHNICAL NOTE TN-01/2 STATISTICAL MEASURES OF MARKSMANSHIP Richard F. Johnson Military Performance Division February 2001 U.S. Army Research Institute of Environmental Medicine) and was determined by utilizing OnTarget TDS software (OnTarget TDS).

Summary:

If your duties or circumstances lead you to carry a shotgun for self-defense when outdoors, we encourage you to make use of shotshells utilizing a pattern-controlled shotcup and copper-plated shot pellets. As tested, pattern-controlled #1 buckshot presents an interesting alternative to the more traditional 00 buckshot (also pattern-controlled) in that the maximum effective range is the same but the felt recoil is reduced by 23% over the 00 buckshot load. Since there is no difference in the long range performance of the two shells, we recommend the Federal LE132 1B load to maximize range and minimize recoil for the defensive shotgun. For self-defense indoors or in environments that physically cannot exceed 10 yards distance, we recommend #4 plated buckshot at 1250 ft/sec or higher muzzle velocity. You can maximize your shotguns effectiveness by selecting buckshot that is effective out to your maximum planned engagement distance and no further.

Shotgun or sidearm?

Saturday, April 21st, 2018

Shotgun or sidearm? This 1976 Sid Davis police training film for the Pasadena Police Department should help you decide:

Watch the first couple minutes, with the shootout and its immediate aftermath. How far away did the robber appear to be? And what kind of spread should you expect from buckshot at that range? I’m going to go out on a limb and suggest that pellets should not be hitting six feet off line at a couple dozen yards.

I was pretty surprised when they set up the scenario at the target range at “the same distance, about 50 yards.” OK, at that distance you should expect a fair amount of spread, but more like a four-foot diameter — which is still plenty dangerous on a crowded sidewalk.

The attitude toward revolvers is, well, it’s quite optimistic: “Most cops get a fair amount of practice with their sidearms, but they don’t fire a shotgun very often.” I especially liked this comment: “With his thirty-eight, Don would have hit only the suspect. One shot.” Yeah, a cop shooting a double-action revolver at 50 yards, while getting shot at, is going to hit the suspect with one shot?

Enjoy the whole thing.

It’s hardly the megawatt monster military scientists dreamed of

Wednesday, April 18th, 2018

The U.S. Navy’s most advanced laser weapon looks like a pricey amateur telescope, and, at just 30 kilowatts, it’s hardly the megawatt monster military scientists dreamed of decades ago to shoot down ICBMs, but it is a major milestone, built on a new technology:

The mission shift has been going on for years, from global defense against nuclear-armed “rogue states” to local defense against insurgents. The technology shift has been more abrupt, toward the hot new solid-state technology of optical-fiber lasers. These are the basis of a fast-growing US $2 billion industry that has reengineered the raw materials of global telecommunications to cut and weld metals, and it is now being scaled to even higher power with devastating effect.

Naval Laser by MCKIBILLO

Industrial fiber lasers can be made very powerful. IPG recently sold a 100-fiber laser to the NADEX Laser R&D Center in Japan that can weld metal parts up to 30 centimeters thick. But that high of a power output comes at the sacrifice of the ability to focus the beam over a distance. Cutting and welding tools need to operate only centimeters from their targets, after all. The highest power from single fiber lasers with beams good enough to focus onto objects hundreds of meters or more away is much less — 10 kW. Still, that’s adequate for stationary targets like unexploded ordnance left on a battlefield, because you can keep the laser trained on the explosive long enough to detonate it.

Of course, 10 kW won’t stop a speeding boat before it can deliver a bomb. The Navy laser demonstration on the USS Ponce was actually half a dozen IPG industrial fiber lasers, each rated at 5.5 kW, shot through the same telescope to form a 30-kW beam. But simply feeding the light from even more industrial fiber lasers into a bigger telescope would not produce a 100-kW beam that would retain the tight focus needed to destroy or disable fast-moving, far-off targets. The Pentagon needed a single 100-kW-class system for that. The laser would track the target’s motion, dwelling on a vulnerable spot, such as its engine or explosive payload, until the beam destroyed it.

Alas, that’s not going to happen with the existing approach. “If I could build a 100-kW laser with a single fiber, it would be great, but I can’t,” says Lockheed’s Afzal. “The scaling of a single-fiber laser to high power falls apart.” Delivering that much firepower requires new technology, he adds. The leading candidate is a way to combine the beams from many separate fiber lasers in a more controlled way than by simply firing them all through the same telescope.

There’s much, much more.

We used to own the night

Thursday, April 12th, 2018

We used to own the night, but so many night-vision devices have fallen into enemy hands that we no longer do:

Taliban fighters, many now outfitted with night vision goggles and infrared lasers, have more than doubled nighttime attacks on Afghan and U.S. troops between 2014 and 2017, according to a new report from The New York Times.

This has presented U.S. military officials with quite the conundrum: Do we give more night vision to our Afghan allies to protect themselves, even if that gear has a good chance of ending up in Taliban hands?

[...]

The Pentagon sent 210 night vision devices to the Afghan National Army 215th Corps in Helmand Province, for example, but only 161 of them were returned. While the 215th Corps attributed the discrepancy to “battle losses,” according to the Times, it’s also quite common for Afghan troops themselves to dump their own gear on the black market to make a quick buck.

“Free reminder: almost every item issued to Afghan soldiers ends up in Taliban hands,” C.J. Chivers, a Times journalist and Marine vet, wrote on Twitter. “If U.S. opts for wide issue of night-vision equipment, within months the Taliban will have even more.”

This was entirely predictable.

Let’s talk about bombs for a minute

Tuesday, March 13th, 2018

Let’s talk about bombs for a minute, Greg Ellifritz suggests:

This week, a Utah high school student was arrested after he attempted to detonate a large backpack bomb in his school. Luckily, the bomb malfunctioned and the school was evacuated before anyone was hurt.

Those of you who have taken my “Response to a Terrorist Bombing” class might remember how I discussed that in worldwide terrorist events, the trend is moving more and more towards combining bombs and guns in the attack.

If you find yourself in the middle of a mass shooting, you must be prepared for the coming bomb blasts. If you survive a bomb blast, you must be looking out for people with guns shooting up the evacuation site. That’s simply the reality of modern terrorist attacks worldwide.

This particular incident had only a bombing component (likely because it was committed by a lone high school student without any true support of a terrorist network). I predict we will see more and more of these as well.

After the Las Vegas concert shooting and the Florida school shooting, people are becoming more conscious of the potential carnage that can be inflicted by a deranged gunman armed with a semi-automatic rifle and a lot of ammunition. There are currently multiple social and political pressures being applied to limit the purchase and/or possession of these rifles. While I don’t personally think that tactic will be effective at reducing mass casualties in a terrorist attack, I believe it will become harder and harder to legally acquire semi-automatic rifles in the future.

What will the terrorist resort to if he can’t get a rifle and lots of ammo? You guessed it…bombs. Look at terrorist attacks worldwide. In countries with very strict gun control, we see terrorists use bombs more often. Bombs are easy to make and can cause massive casualties if placed in the right location at the right time. Bombs also bring a disproportionate amount of media attention, which is exactly what the killers and terrorists crave.

If you predict that semi-automatic rifles will become harder to legally acquire in the future, then you have to be prepared for more terrorist bombing incidents.

Be careful what you wish for.