Isegoria

The exponential growth in electronic computational power has, Azar Gat (War in Human Civilization) notes, transformed naval and air warfare:

At sea, the heavily armored, big-gun capital ships have vacated the scene, and warfare is waged offensively by electronic guided missiles and defensively by electronic disruption and interception systems. Similarly, air warfare, once based on the kinetic capabilities of planes and their armament, now relies primarily on electronically guided weapons and electronic defensive systems. Both at sea and in the air, victory now depends on who is one step ahead of its rivals in these crucial techno-tactical spheres.

The medium in which land warfare takes place is immeasurably more complex than those of sea and air warfare, because of both the numbers of combatants involved and land’s complex topographical features. But at least since the early 1980s the direction has been clear to those who grasped the broader context. The revolution that land warfare is undergoing is no less profound and far reaching than that generated by the mechanization revolution and the introduction of the tank and other AFVs. It was J. F. C. Fuller, the leading pioneering theorist of mechanized warfare, who firmly placed the mechanization revolution in war within the context of the second industrial revolution and thereby helped people understand its full significance and scope. Incredibly, as early as 1928, he looked further ahead, predicting that the third revolutionary wave of the future — which would shape war, as well as all other fields of life — would be “electric and robotic” (the word electronic did not yet exist).

Let us focus on the tank, a product of the second mechanization revolution and the backbone of land warfare for about a hundred years. Ever since World War II, tanks have been optimized, primarily to fight other tanks, and second, to withstand hollow charges. Their main armament is a high velocity gun firing kinetic projectiles. Half of their 60-70-ton weight in most armies consists of heavy armor, which in turn requires a 1500 horsepower engine.

However, tanks will no longer come within kinetic firing range of each other, and will be discovered and attacked at much longer ranges. This is no different than with the mighty battleships of WWII’s Pacific theater, which never came within firing range of each other.

[…]

The wholesale destruction of the hapless Armenian army in the 2020 war against Azerbaijan, like the stranded and harassed Russian convoy en route to Kiev and the image of the Russian armored battalion massacred during its attempted river crossing in the Donbas, with the shattered bridge in the middle, starkly demonstrates the current reality. The same can be said of the rash retreat from the Saluki wadi by the Israeli army’s 401st Brigade Merkava Mark 4 tanks during the Second Lebanon War (2006) when faced with second-generation Russian Kornet anti-tank missiles fired by Hezbollah.

[…]

This does not mean that the tank and other fighting vehicles are history. But the answer is not to be found in further reinforcing the heavy armor or in improved tactical practices, clumsy as Russian tactics proved to be. Rather, the answer lies in a full-scale adjustment of land fighting vehicles to the ongoing electronic revolution — above all, in adopting active defense systems, such as the Israeli Trophy and Iron Fist, now purchased and installed by the US, German, and British armies. Active defense means electronic detection, disruption, and interception of incoming projectiles, launched from land or from the air — the same revolution that sea and air warfare have already undergone.

[…]

The current reality, in which being detected on the modern battlefield means almost assured destruction, will no longer hold. A two-sided game reopens. Thus, battlefield survival and success will depend on the question of which side possesses the last word in terms of offensive and defensive electronic systems and counter-systems for detection, attack, and disruption. As in air and sea warfare during the electronic age, it can also be expected that when one side holds a decisive advantage in these systems, we shall see crushing, almost one-sided victories in regular conventional land warfare.

[…]

While electronically guided projectiles are already widely and effectively used in the Ukraine War, electronic interception and disruption system are largely absent. The trench warfare stalemate that has attracted so much attention — as if we were back one hundred years to World War I — may be a function of this imbalance, as armored fighting vehicles are paralyzed by the lack of effective active defense.

[…]

Indeed, relying on electronic detection and interception systems enables a drastic reduction in the armor of fighting vehicles for what is necessary against small arms, shrapnel, and blasts. Thus there is an expected reduction in their weight to about 10 to 25 tons; a parallel reduction in engine size and weight; and design re-orientation to electronically guided defensive and offensive systems. This, I believe, is the direction in which land warfare and land weapon systems is heading in the electronic-computerized age.

Lockheed Martin’s experimental X-59 Quiet Supersonic Technology aircraft, or QueSST, built by the company‘s Skunk Works for NASA, provides no traditional forward visibility to its pilot:

Ultimately, it’s planned that the X-59 will achieve supersonic speeds over land that create no more than a sonic ‘thump’ — rather than the ‘boom’ associated with previous supersonic transports. That could convince U.S. and international regulators to change the laws governing supersonic commercial aviation.

This is all part of an overall design that’s specifically intended to reduce the kinds of sonic booms that have long been an obstacle in the way of commercial supersonic flight over land. With such a long snout ahead of them, the X-59’s pilot instead relies upon the eXternal Vision System (XVS) and an array of forward-facing high-resolution cameras. An aperture for the 4K camera used in the XVS can be seen in these new photos, located atop the nose, broadly above where the canard foreplanes are located.

Britain’s Royal United Services Institute and the US’s Pentagon have acknowledged that Russian electronic warfare is reducing the accuracy of American guided weapons, including JDAMs and HIMARS rockets:

In particular, Withington pointed to the Russian Army’s R-330Zh Zhitel, a mobile truck-mounted jamming system specifically designed to disrupt GPS and satellite communications in the 100 MHz to 2 GHz wavebands. “Signals from the U.S. GPS satellites which JDAM kits use are transmitted on wavebands from 1.164 GHz to 1.575 GHz,” according to Worthington. “These fall squarely within the R-330Zh’s catchment area.”

Worthington claims to have seen official documents that put the R-330Zh range at 18.6 miles, with a 10kW-strong jamming signal. This is “notably stronger than the strength of the GPS signal arriving from space,” he noted. “Moreover, the closer the GPS receiver is to the R-330Zh’s jamming antenna, the stronger the jamming signal becomes.”

In theory, the Selective Availability Anti-Spoofing Module upgrade to JDAM in the early 2000s should ensure that JDAM will only respond to authorized M-Code encrypted military GPS signals. However, Russian jammers may still be able to disrupt the signals through “sheer brute force” jamming beams, Withington said.

Russia could also intercept M-Code signals and retransmit them with slight alterations to a JDAM, causing the bomb to miss. Efforts to bypassing Russian interference by using signals from multiple GPS satellites could in turn be countered by employing multiple jammers.

Russia’s counter-GPS efforts are part of a massive electronic-warfare campaign that has also disrupted Ukrainian radio communications and drone operations.

Russian forces “now employ approximately one major EW system per 10 kilometers [6.2 miles] of frontage, usually situated approximately 7 kilometers [4.3 miles] from the frontline,” according a recent RUSI report on Russian tactics. This jamming has contributed to a Ukrainian drone loss rate that RUSI estimates to be as high as 10,000 UAVs per month.

[…]

Nonetheless, Russian electronic warfare has limitations. Emitting jamming beams discloses a jammer’s location, and Ukraine appears to have located and destroyed Russian systems such as the R-330Zh. Ironically, smothering the airwaves with powerful jamming beams may also be disrupting Russian GPS and radio communications.

David Hambling, author of Swarm Troopers, explains drone warfare in Ukraine:

The Navy surface fleet is essentially floating airstrips surrounded by air defense batteries, Austin Vernon says:

Floating airfields are valuable where land bases are constrained or surprise/mobility is critical.

Potential flashpoints with China, like Taiwan or the South China Sea, are more expansive than Europe but aren’t the vast Central Pacific. Airfields, aircraft, land-based air defense, and small utility ships can replicate most of a carrier strike group’s capabilities in a war with China. Aircraft are capable anti-ship platforms, they can keep enemy airplanes at bay, and there are plenty of airfields to fly from. But they cannot clear the way for supply ships nor operate persistently deep in enemy territory. The minimum viable Navy has to handle enemy mines and submarines. Adding offensive mine and submarine capabilities is the next logical step.

Minesweeping capability will be critical for supplying forward bases, keeping Taiwan from starving, and gaining entry to the Taiwan Strait later in the conflict, and the following features could help:

Sonar to Find Mines

Most minesweepers have active sonar arrays to find potential mines. There are low-resolution modes for broad searches and high-resolution modes for investigating potential mines. The Navy might have to adapt less capable off-the-shelf sonar and put those arrays on whatever ships they can scrap together.

Charges to Destroy Mines

A brute force option might be launching depth charges at anything that looks like a mine on wide-view sonar rather than confirming with narrow-band sonar, UUVs, or divers.

Better Mine Triggering Methods

It would be ideal if new decoys could simulate ship sounds and magnetic signatures well enough to trigger mines.

Underwater Micro Drones

Some proposals envision launching small unmanned underwater vehicles from motherships to seek out mines and eliminate them – essentially underwater loitering munitions. These are one of the few technologies that might help US submarines fight in the shallows deep in Chinese territory.

The US may not have air supremacy, so the answer for hunting subs can’t be P-8 patrol planes dropping buoys at every likely hiding place:

More Advanced Listening Network

The US tracked Russian nuclear submarines during the Cold War with a network of sensors in the Deep Sound Channel that transports noises for hundreds or thousands of miles. Most waters in East Asia are too shallow for this layer to exist. A network in East Asia will need more nodes or different technology to work effectively.

These capabilities are highly classified, and there have been suggestions that the US and Japan are improving the existing systems. The Navy has also added low-frequency active sonar with a 160+ km range to their submarine tracking boats. These systems perform much better against quiet diesel subs in shallow water.

China has also built listening networks to counter US submarines.

Underwater Seagliders

Seagliders and wave gliders are a class of drones that loiter in the ocean for months or years to collect data. They are hyper-efficient, often using a few watts. The mission can be as simple as collecting oceanographic data or as complex as tracking enemy subs. These gliders could increase submarine detection capability deep in enemy territory. They have to prove that they are stealthy enough to avoid detection/destruction, and software must be energy efficient to avoid running down the batteries.

Expendable Drone Aircraft

Another speculative option is putting sensors like magnetic anomaly detectors (MAD) on small, inexpensive flying drones. You might be able to buy hundreds of these for the cost of one anti-submarine warfare (ASW) helicopter, increasing the coverage area.

ASW Patrol Boats

There won’t be time to build anti-submarine warfare powerhouses like a Perry-class frigate or Spruance-class destroyer. And the current fleet has no dedicated ASW ship. There will be a need for boats capable of escorting carrier battle groups and convoys. The more desperate the timeline, the more ramshackle solutions will be. Grafting on older sonar arrays and torpedo racks is probably the bare minimum.

The US Navy is complacent, Austin Vernon suggests, after lacking a competitor for so long:

Modern carrier design reflects that. Thankfully physics has little to say about how much a carrier needs to cost. The new USS Ford weighs 100,000 tons. Steel costs ~$700/ton, so the basic materials are only $70 million. Very Large Crude Carriers (VLCCs) are roughly the same size. They cost ~$90 million, barely more than steel and engines. Crew quarters for 5000 sailors, nuclear reactors, radars, catapults, flag accommodations, specialized systems, and general government bloat get you to a $10+ billion ship.

The minimum requirements for a carrier are:

1. Launch full-size aircraft
2. Have space for bombs, fuel, and crew

One option is to design carriers without complex systems. Make the deck long enough to launch aircraft without catapults or arresting wires. Use ramps instead of elevators. Put only the most basic radio or radar. Then use cost-effective marine diesel engines instead of high-performance power plants. Don’t bother with fuel piping. Small trucks can carry fuel from deep in the ship to the hangar. Having ramps at each end of the runway simplifies traffic control. You don’t even need a tower, just a pure flat deck. Forget flag facilities. The admirals can stay on an AEGIS ship if they want fancy screens and wardrooms.

The carrier would be the longest ship in the world at ~1000 meters. The vessel before outfitting would cost ~$300 million if built like VLCCs. Modular construction methods help shipyards complete these ships in less than a year. Crew quarters can be austere to speed construction. Sleeping arrangements would be small cots, there wouldn’t be kitchens (eat MREs) or plumbing (use chemical toilets, bottled water, and camp showers topside), and all laundry could be shipped offsite. A typical VLCC only has twenty crew, so most sailors will be the ~1400 it takes to run seven squadrons of aircraft. Active combat will require a few hundred more solely for firefighting and damage repair. Cutting support functions and features reduces the crew significantly.

The ship will be ~3x the size with half the crew, leaving excess space. That allows aircraft to be kept below deck and protected. Crew quarters can move deep into the interior. The ship can fill the cavities surrounding crew and aircraft storage with closed-cell aluminum foam. These foams are fire-proof, absorb energy, and are impermeable to water to prevent flooding.

The design could end up near ~$1 billion with rapid development and construction times once the Navy commissions a suitable dry dock.

Assume both sides have omniscient satellite coverage and very capable AI/ML:

The first goal is to degrade missile seeker performance. Missiles can use radar, infrared, visual, and electronic listening sensors for terminal guidance. A small escort ship could have a powerful jamming suite to spoof the satellite’s synthetic aperture radar, jam radar frequencies the missiles use, and degrade satellite-to-missile communication. It is best for it to be separate from the carrier to thwart home-on-jam seekers. Smoke can obscure visual observation, and many aerosols can degrade the infrared spectrum. For good measure, you can spread diesel on the ocean and light it on fire. Chaff can distort any unjammed radar signals. None of these methods are perfect, but they all degrade missile performance. The cost is marginal compared to the billions of dollars a missile salvo would cost. Satellites will monitor China’s mainland for launch plumes, giving the carrier group ~15-30 minutes of warning. The carrier crew can launch its planes, drain and park fuel trucks, secure tools in lockers, store munitions, and go to shelters during the missile flight time.

Missiles won’t be the only users of AI/ML. Instead of bespoke close-in weapon systems that cost $10 million, you can hook up cheap infrared cameras and iPhone-level computing to 20 mm and 40 mm cannons. You are looking at $100,000 per gun instead. An ideal situation might be spending $100 million to buy 1000 cannons and putting them on a few glorified barges near carriers (but outside of the smoke/aerosols). These guns have a several thousand meter range, providing several long seconds to wreck incoming missiles. And because we have advanced AI/ML, aiming will be very accurate.

When we do the math, fifty $20 million missiles equals a $1 billion carrier. ~100,000 bullets from our guns equal one missile. We can afford to turn the sky black with lead. Our defenses can get off around 50,000 per second. Most CIWSs don’t even bother using explosive shells, but that is an option to make the ammo more effective.

Assume China drains its entire inventory of ~200 DF-21D and DF-26 missiles in one salvo. The SM-6 and SM-3s from the guided missile ships will get a few – call it 10%. Our guns will get off 150,000 rounds – almost 1000 rounds per missile – even if the Chinese time the attack perfectly. Any staggering of the missiles increases the rounds per missile dramatically. Of course, some will still probably get through. A portion will be confused by the smoke/aerosol/chaff/fire/jamming countermeasures. Assume a few hit the flight deck of our carriers. They’ll punch some holes and get buried in aluminum foam. Maybe they push some damage into the empty hangar.

Thousands of sailors will scurry to put out any localized fires. Then they’ll drive some forklifts out of shelters to pick up steel plates, beams, and extra bails of aluminum foam to take up the ramps. They’ll cut up damaged deck plate pieces, toss in the foam bails, insert beams, and use hundreds of welders to attach new plates. The crew will repair the damage before the planes need to divert away.

These defenses also work well for drone swarms. Iranian Shaheds would struggle to sneak by the 1000 guns with independent eyes, and their 80-pound warheads would barely dent the paint. The ramps could have blast doors to keep any drones from wandering down toward the planes.

The strike group can carry on and do its job.

What does a “built-to-win” fleet look like? Austin Vernon offers some suggestions:

First, carriers will still dominate the fleet! Without air cover, you lose. The aircraft will remain the same size because of payload and range constraints whether humans fly them or not, limiting the utility of smaller carrier designs. Carriers are not as vulnerable as assumed, either. In WWII, bombs and missiles sunk only one US fleet carrier. Today’s carriers are 5x the size, yet modern anti-ship missiles and WWII munitions have similar explosive punch. The main questions are how fast repairs happen and how well the crew can put out fires. Escorts will provide warning, defense, and absorb hits.

The US Navy has limited ship-killing and land attack ability outside of aircraft and submarines. Nine F-18s, each carrying ten 1000-pound bombs, have more explosive power than a Burke-Class destroyer’s vertical launch tubes, and the destroyer must return to port to reload!

The Navy could benefit from several improvements to support carriers and increase offensive ability:

Ships That Can Brawl:

The Navy needs ships that can take a punch and have the firepower to deal damage.

Survivability needs to be a priority. Modern warships have mostly given up on armor, but there has been significant progress in armor technology in tanks that could offer a boost in survivability. Ships have more room and mass allowance than tanks, opening up more options. Battle damage considerations, especially around fire, are always critical. Sensors on current Navy ships often have more capability than necessary, are challenging to repair, and are extremely sensitive to damage. A fighter aircraft-size radar would be more than adequate on most ships, allowing for the storage of spare modules. All maintenance must be as easy as swapping modules, similar to the Army’s tanks. Ships will get hit by missiles, and some will sink or burn, but that doesn’t mean that one shot should take them out of the fight or that the crew must go down with the ship.

Stealth is another key to survivability. Any reduction in radar, acoustic, thermal, electronic, or visual signature helps delay detection and makes the ship less enticing for precision-guided munitions. Tall vertical missile launch tubes and large radars are the worst offenders in increasing signatures.

Engineering, economics, and practicality all point towards warships needing an incredible density of short-range air defenses composed of electronic warfare, decoys, smaller missiles, guided rockets, and guns. Most point defenses should have independent targeting systems for robustness. Reliability and quick reaction times matter more than interception range.

Surface warfare capability must increase, especially in the 30-150 km range. Naval guns, rocket artillery, and rocket-launched torpedos are all options. Modified-for-sea-duty M270 Multiple Launch Rocket System launcher rails could provide sustained offensive firepower at 20,000 pounds per hour per launcher, could reload at sea, and use everything from 30 km range surplus rockets to the 500+ km range Precision Strike Missile. 8″ guns could massively increase range and firepower compared to today’s 5″ guns. An experiment in the 1970s put an 8″ gun on a small destroyer, proving the concept. And there is a faction that wants to reactivate and modernize the Iowa-class ships, bringing 16″ guns back into the inventory.

These ships are only valuable if they are manufacturable. The easiest way to improve manufacturability is to remove excess features. The worst offenders are massive $300 million radars, helicopters, and vertical missile tubes. All of these systems are complex, fragile, and hideously expensive. Deleting these features or substituting simpler systems could reduce the size of a destroyer by 70%. More shipyards can build them, and the construction time and cost will decrease dramatically.

A classical destroyer, a more narrowly-focused submarine, and an anti-air-focused cruiser would be examples of needs within this paradigm. The destroyer could serve as a carrier escort or operate in independent squadrons. The Navy could build a submarine without vertical launch tubes, special forces accommodations, and other extraneous features in numbers to disrupt enemy shipping and subs. The cruiser would provide additional short and medium-range anti-air capability, especially for handling sea-skimming missiles.

Simple Support Craft:

Several support capabilities have little peacetime utility but would have insatiable demand during a high-intensity conflict. Anti-submarine patrol boats, minesweepers, amphibious landing equipment, and escort carriers for submarine hunting helicopters and scout drones are the main culprits.

These vessels don’t fight the enemy fleet directly, allowing them to be simple, small, and possibly built on commercial hulls. The main requirements are to do one job well and to be built in huge numbers affordably. The Navy’s attempt to consolidate many of these capabilities into the Littoral Combat Ship (LCS) has been a disaster after cost and complexity spiraled out of control.

The Navy needs new models in production to support a small number of active duty ships for training, some in reserve, and unconventional shipyards certified to produce high volumes.

Better Passive Sensors:

Controlling electronic emissions will be a matter of survival for Navy Battle Groups, especially early in a conflict. Even using radar aircraft like the E-2 can betray the general area of a carrier group. There is a catch-22 with radar. It might provide more warning of missiles, but using the radar will make the group a missile magnet. Incredible amounts of short-range air defense are helpful because the engagement ranges could be very close.

Passive sensors, like infrared cameras, to detect missiles and other combatants would make it easier to turn the radars off until a battle commences. Drones can provide over-the-horizon sensing that ship-based radar and optics can’t, increasing warning time. Bad weather can degrade the infrared and visible light spectrums, but the enemy suffers, too. Their scouts and missiles will use radar that warns of their attack.

Sea gliders, satellites, and over-the-horizon radar stations are other ways the Navy can gather intelligence, though many of these will also be early targets for the Chinese.

Air Superiority Fighters:

The Navy is in worse shape than the Air Force because they have no equivalent to the F-22. Incremental improvements to the F-35 are an option for improvement while waiting for the F/A-XX program to mature.

There are a few areas the Air Force needs to address, Austin Vernon suggests:

Reducing Sensor Vulnerability:

The Chinese see the US Air Force’s big, slow sensor platforms as a weak link. Many speculate that the purpose of the Chinese J-20 stealth is to sneak around combat air patrols and shoot long-range missiles at helpless radar planes and tankers. Putting smaller radars, cameras, electronic listening, and jammers on many drones would reduce sensor vulnerability. The Off-Board Sensing Station program is developing the capability to operate these drones beyond line-of-sight with limited satellite coverage, a critical requirement for the vast Pacific Ocean. The distributed drones will almost certainly cost more because it might take one hundred XQ-58-size drones that cost several million dollars to equal the coverage area of one E-3 or E-7. The Air Force could also use the B-21 airframe as a sensor/coordination platform.

Anti-Missile Fighters:

The Air Force needs inexpensive anti-missile combat air patrols over likely targets. Short-range, guided munitions like the $25,000 APKWS 70mm rocket can dispatch most threats. An F-16 fighter recently downed a cruise missile in a test using one, and the US already manufactures ~20,000 APKWS kits a year for air-to-ground purposes.

Traditional fighters can fulfill this mission, but drones like the XQ-58 could cover more potential targets and better handle attacks from multiple directions. They can also maintain near-perpetual readiness waiting on the launch rails, allowing a surge of launches within seconds without the stress of keeping crews at high readiness.

Supersonic Stealth Fighter:

The F-22 being out of production is a liability because the F-35 is not nearly as optimized for air-to-air combat. Restarting production could be a low-risk option until the NGAD fighter enters service. The history of fighter aircraft suggests a massive edge for better capability, making the F-22 hard to replace with lesser aircraft. A historical example is the Hellcat having a 19:1 kill-to-loss ratio against the Japanese in WWII. The Chinese put so much effort into attacking airfields to avoid fighting the F-22 in the air.

A relevant supersonic stealth drone will likely be about the size and cost of a traditional fighter with more technical risk and longer development timelines than restarting F-22 production. You can always put an AI pilot in an F-22.

The template for a cheap, low-capability fighter drone already exists in the XQ-58. There is a risk that it would score zero kills against 5th-generation fighters and cheaper anti-drone missiles are on the horizon to negate swarm attacks. But, the XQ-58 is an available design that can scale rapidly if testing or experience proves it useful for battling enemy fighters. There may be other simplified drone types worth testing, like a stealthy dogfighting drone that only uses guns.

The Air Force must keep airfields near Guam and Okinawa in the fight, he notes, to use its hundreds of F-22 stealth fighters and thousands of F-15s and F-16s:

RAND makes the case that the best option for protecting aircraft during a war is dispersal, selective hardening, and using cheaper shelters that provide some protection against shrapnel or cluster bomblets but not bombs. Leaving most aircraft shelters empty can obfuscate where the planes are, lowering the accuracy of precision-guided munitions. Increasing active defenses like interceptor missiles is critical, too. Many of these strategies are already underway. The combined effort makes launches of $20 million ballistic missiles look less appealing.

Cheap drone-based bombs have taken their toll on armored vehicles in recent wars, which might pave the way for motorcycles, of all things:

Motorcycle are fast, nimble, and outstrip even tracked vehicles in off road capability. In the woods a bike can get between the trees right under the densest canopy and travel along single track trails no wider than what a person or deer might walk, and wind between and, for the skilled enduro rider, Over! massive rocks and terrain that would rip a tank apart.

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100lbs of kit (Equivalent to a heavy fighting load for a long patrol) is fairly easily and regularly carried by amateur adventurers on their bikes as they head out to the woods, or go on a cross-country tour. Allowing many to go hundreds of miles off-road at paces averaging well above walking or even running, and then instantly get back up to highway speeds as soon as they find one.

[…]

The off-road capability means obvious or watched routes are easily avoided, concrete barriers are easy to skirt around or between (or in the case of enduro riders: hopped), and checkpoints set up to control car traffic easily circumnavigated. similarly most dual-sport bikes can ford up to waste deep (or even chest deep with a homemade snorkel) water and at 300-700lbs total weight, depending on bike and equipment, most bikes can be transported in civilian small boats (this is how many adventurers surmount the Darien gap on trips to South America), allowing waterborne insertion without specialized landing craft, and the evasion of bridges that act as chokepoints.

Then once the bike is stopped it disappears completely.

Armoured vehicles are large, made of steel, and have large, HOT, engines which drive Wheels or tracks, which in turn generates a great deal of friction, heating those elements massively. Thus Satellites, radar, And infrared imagining have a relatively easy time of finding them.

Just on the face of it, with no concealment, bikes are difficult to detect via satellite, the width and length of a bike viewed directly above resembles the profile of a log or trash bins or small pile of rubbish more than any other vehicle an analyst might be looking for. And that’s if the satellite has the resolution to see the bike at all. Satellites also have the weakness that they only get individual snapshots of an area, meaning any indirect movements (not in a straight line) don’t betray their destination if seen and, until machine learning improves, are highly dependent on analysts actually looking at images and drawing conclusions, thus inherently limiting how realtime the information they can (a troop movement might take an hour to be identified once the satellite passes at which point a vehicle can be hundreds of kilometers way).

Similarly the radar cross section of a bike is shockingly small. Now a radar cross section is the size of a shape estimable from radar detection. Stealth Fighters might have a radar cross section as small as 1cm², so ably have the designers limited radar bouncing back, but then they need to since there is no clutter or concealment around a jet flying through empty air over enemy territory, and very little naturally travels faster than sound. However For most objects their radar cross-section is largely proportional to their size: a human for example is about 1m², a non-stealth light aircraft 3-5m², etc.

Whereas the radar cross section of a light vehicle can be 10-50m² (~+10 to +20dbm), and tanks closer to the 40-100m² (~+15 to +20) end of that spectrum, well above their actual size due to their metal composition and shape creating natural corner reflectors, motorcycles have a max radar cross-section just under 10m²(10dbm), which only occurs in spikes 90 degrees to the side as well as smaller ones to the immediate front and rear, For about 280 degrees of the spectrum the radar cross-section of a Motorcycle is smaller than that of it’s rider (average of about 1m², or 0dbm), rendering it pretty much indistinguishable from clutter, unless it starts flying through the air or sailing a calm sea ( or I suppose travelling a perfectly flat desert). On an open highway At highway speeds a motorcycle would be detectable by aircraft radar, since in nature only Cheetahs and falcons move that fast, a computer could reliably distinguish that from background noise, if it had a good angle… but at an off-road pace of 15-30km/h? Fat birds and dear travel that fast, hell the tips of tree branches probably reach that speed shaking in the wind. And geese, with a ~30cm² (-5dbm) radar cross section, comparable to the bike’s low end cross section, Regularly fly at 50-70mph (80-110kph), so even on open roads at legal rural “highway” speeds, there’d either be a large number of false positives or good chance the bikes go ignored by the radar software/operator, or undetected.

[…]

So summing up: bikes are incredible.

They provide a tool in many ways better than an armoured troop carrier, at a fraction the cost, have the best stealth of any vehicle under a 100 million dollars per unit, and given the easier time radar has at detecting supersonic airborne units… perhaps the best stealth period. They perfectly combines the versatility of foot travel, with the ability to get up to highway speed in under 10 seconds, and give fighters the ability to carry a full 100lb fighting load without significant physical exertion.

No wonder they are currently being used by Insurgents and militias across the middle-east and Africa, and no wonder many of the armies fighting said militias have started to replicate their tactics.