9
$\begingroup$

Working with a world with relatively high industrial technology, including good materials technology but no energy weapons or the like but modern-day ballistic technology.

Why not use the equivalent of pavise shields in combat, especially if the positions are fairly fixed? These would be fixed against the ground, rather than handheld in any way.

  1. I imagine if made of appropriate materials, they'd stop most small arms fire. They essentially would be sandbags but directional.

  2. Energy from bullets would just be transferred against the ground, so many considerations about dissipation with body armor would become moot.

  3. It would have its weight considerations, but it's a lot lighter than sandbags. Simple technology such as a car and wheels could get it setup.

  4. It could be used a mount to help stabilize heavy weapons.

What would be arguments against them, besides the prominence of indirect fire? And if I wanted to go higher tech with them, couldn't they work with powered exoskeletons, becoming essentially a shield that is lowered from the back and put in the ground, kind of like Sundowner from Metal Gear: Revengeance (although that went thoroughly into Rule of Cool).

$\endgroup$
  • 8
    $\begingroup$ "Lighter than sandbags"? I assume you mean already "full" sandbags (as in Iraq and other desert environments the bags, and Hesco barriers in some cases, were easy to carry and there was plenty of sand around to fill them once needed). $\endgroup$ – LinkBerest Sep 2 at 17:41
  • 2
    $\begingroup$ because armies don't stand in formation during combat anymore? So they are basically useless. $\endgroup$ – John Sep 3 at 4:33
  • 1
    $\begingroup$ @John: A pavise shield specifically is a form of shield to cover an entire soldier, unlike smaller shields who were to be used in shield formations like Viking shield wall or Roman testudo. Or did you really mean "because battles are no longer as stationary as they once were"? $\endgroup$ – phresnel Sep 3 at 11:16
  • 3
    $\begingroup$ Points 3 and 4: "car and wheels" to move it around, and "use as a mount to help stabilize heavy weapons". Congratulations, you have just reinvented an inferior form of tank... $\endgroup$ – Chronocidal Sep 3 at 11:47
  • 1
    $\begingroup$ @phresnel because battles are neither stationary nor static. by standing in formation I was referring to volley musket fire. $\endgroup$ – John Sep 3 at 12:45
14
$\begingroup$

Things like that have been used in niche applications.

My conclusion from these examples is that pavise-style shields work only in very special conditions, and that general issue would be either lighter body armor or heavier vehicle-mounted armor, not this "too heavy to carry, to light to protect" intermediate size.

$\endgroup$
  • 1
    $\begingroup$ The vehicle mounted version is still very popular though! You just need to protect the crew from all directions (and the top) so they get very heavy which means they are usually based on powerfull yet stocky platforms which makes firing the gun unwieldy. So these days the guns are mounted on smaller, swivel-able boxes on top of the shield-carrying cart. Yes I am talking about the tank. Many (mostly games) maintain the fiction that tanks are the extension of cavalry but if you look at the earliest iterations they are clearly testudo-formations with tracks. $\endgroup$ – Borgh Sep 3 at 7:02
  • $\begingroup$ @Borgh, but their use was as cavalry, to break a line but not hold a position. $\endgroup$ – Separatrix Sep 3 at 7:23
  • $\begingroup$ Yes but "breaking a line" is not unique to cavalry. I'd argue that mobility is the USP of cavalry and at sub-10km/h early tanks were not that mobile. Early tanks were built for all-terrain capablity and protection, not speed. $\endgroup$ – Borgh Sep 3 at 7:43
  • $\begingroup$ Generally, early tanks were meant to support infantry, indeed making them more like a testudo than cavalry. They would plow the way through trenches with infantry following behind to secure the gap, while also providing cover from machine gun fire. $\endgroup$ – Benjamin Wandio Sep 3 at 10:28
  • $\begingroup$ Tanks were initially used for supporting infantry assaults due to their low speed, but a second type of "Cavalry Tanks" were in use by the end of WW1 which did take on the cavalry role of harassing the rear whilst the heavy "Infantry Tanks" continued to support the assault. $\endgroup$ – Kyyshak Sep 3 at 11:21
12
$\begingroup$

Modern-day small unit warfare (where personal shields would be relevant) is based on mobility and fire-and-move tactics where the goal is to outmaneuver an enemy force to deny it a defensible front. To that end it is in the warfighter's interest to stay light on his feet while carrying as much ammunition as possible. During an assault on an enemy position a small unit may have to advance and withdraw many times to in order to achieve a tactical advantage. While defending a position from an enemy assault the unit may quickly followup with its own counter-assault. Given that the modern warfighter is already humped up with as much gear as he can physically carry and be effective in that environment it seems unlikely that the additional burden of a heavy personal shield would be welcome or net effective since other gear, likely ammo, would have to be sacrificed to make room for it. (Although infantry robotics, which are no longer the realm of sci-fi, may soon change that.)

Personal shields would also have questionable effectiveness against the more serious threats to warfighters such as RPGs and grenades, machine guns .30 cal and above, mines and IEDs, or even small arms fire effectively delivered (e.g. ambush). The extent that an injured warfighter would be willing or able to carry a shield is also questionable.

Modern warfighters are trained to use terrain and structures for cover and concealment, and against other infantry that is very effective. The stalemates of WW1 proved that. A shield on the other hand would provide relatively limited cover and no concealment on the battlefield. I suspect that is the fundamental reason why history has rejected the pavise for modern warfare.

$\endgroup$
8
$\begingroup$

Autonomous drone shield bearers.

Samuel 17

4 And there went out a champion out of the camp of the Philistines, named Goliath, of Gath, whose height was six cubits and a span.

5 And he had an helmet of brass upon his head, and he was armed with a coat of mail; and the weight of the coat was five thousand shekels of brass.

6 And he had greaves of brass upon his legs, and a target of brass between his shoulders.

7 And the staff of his spear was like a weaver's beam; and his spear's head weighed six hundred shekels of iron: and one bearing a shield went before him.

If you are in a fight it is nice to have a shield. Even nicer to have someone carrying it for you. In your future (as now!), the public is wary about having AIs with lethal force. Offense is reserved for humans. Defense however is another matter.

The drone shield AIs are in constant communication with each other but also make decisions independently: flocking behavior. They realign and redeploy according to the movements of those they are designated to protect, and their own perception of offensive threats. These would be fun to write, because the drone shield AIs will surprise you.

$\endgroup$
  • 1
    $\begingroup$ Any shield is a weapon if you push it hard enough in the other guy’s face. I would not like to be mobbed by any drone swarm massive enough to be a functional shield! $\endgroup$ – Joe Bloggs Sep 3 at 6:05
  • $\begingroup$ @Joe Bloggs I think what matters here is public perception, if they do not act as weapons they will not be decried as scary AI weapons $\endgroup$ – lijat Sep 3 at 9:26
  • $\begingroup$ @JoeBloggs - massive riot bots like BigHero6 might be a good tool against crowds. $\endgroup$ – Willk Sep 3 at 13:42
  • $\begingroup$ @Willk: Being kettled by a giant marshmallow robot? That would either be awful or awesome, and I’m not sure which... $\endgroup$ – Joe Bloggs Sep 3 at 16:36
4
$\begingroup$

You need to carry them around which hampers your ability to remain undetected and move quickly. Plus, given modern technology, they're limited in their usefulness:

enter image description here

It's not the US independence war or World War I any more where a thousand guys with embarrassingly bad guns on each side fire at each other, two dozen of them actually hit something, and finally they engage in bayonet combat man vs. man.

You shoot someone from 1-2 kilometers away, and you have a gun which fires a bullet that will go right through a complete vehicle, let alone a puny little shield that a man can carry. Or, you do not shoot at all, but mark the target with a laser and have a drone do it. Or something.

$\endgroup$
  • $\begingroup$ Guns worked just fine in WWI, trenches were built on the western front precisely because they were so effective. Advancing in rank with rifles accurate to distances of hundreds of meters and machine guns filling the air with lead is a short lived and poorly thought out plan. $\endgroup$ – Lord Drake Sep 3 at 18:29
2
$\begingroup$

Ballistic shields are used in many police applications, as well as less armoured shields for riot and crowd control (where the threat is not considered to be firearms). This company offers a wide range of ballistic protection, including hand held shields, mobile shields and even "kits" to build defensive bunkers.

However, these sorts of devices are heavy, bulky and impede the mobility of soldiers. As a matter of fact, they don't even solve the greatest issue facing soldiers, which is overhead protection. What soldiers might really like in a defensive position would be something like a table with short, collapsible legs capable of protecting them from a shell burst overhead. Placed over the top of a fighting position (shell scrape, individual trench or fighting position), this sort of overhead protection would be appreciated.

Except that to be able to protect the soldiers from the blast and splinter effect of an airburst they would be carrying around something with the equivalent protection of at least 18" of earth. Considering that Russian weapons have grown in mass and firepower, the protection provided by 18" of Earth, while possibly sufficient for 122 mm howitzer or "Grad P" multiple rocket launchers, now has to contend with the equivalent of 152 mm "smart" rounds or even 300 mm multiple rocket launchers delivering their ordinance in a matter of seconds.

enter image description here

BM-30 Multiple Rocket Launcher

So these things would be massive and a huge pain to carry, plus they would need to be properly "bedded" into the ground, which can be tricky depending on what sort of ground you are on. This would be an engineer task, while the ordinary soldiers would be using corrugated metal, wooden beams or logs and other improvised materials to build their own overhead protection.

enter image description here

Laying down a supporting structure

enter image description here

*Cross section from a military manual

enter image description here

What the end result might look like, assuming that is an entryway under the three layers of logs

Since your engineering troops and transport resources are always in high demand, training the troops to make their own expedient cover out of local materials seems to be a much better use of resources.

$\endgroup$
2
$\begingroup$

Tanks

Would your shields be heavier than tank armor? Because we have weapons that can defeat quite thick metal armor. The history of warfare is a competition between offense and defense. If, for some reason, sitting still where indirect fires can target you all day were a tenable strategy, then attackers would simply switch to higher-velocity rounds. Why does this work? Physics.

Armor

Normally, we think of ballistics in Newtonian terms, and consider the momentum of the projectile vs. the hardness/tensile strength/energy distribution properties of the armor. For small projectiles moving at a low Mach number, this framework is adequate. The essential point is that we are thinking about a solid vs. solid collision, and modelling the result.

Armor penetrators come in two varieties: chemical or kinetic. They both work on the same principle: switch from solids to liquids, which can be easily penetrated and have close to 0 tensile strength (resistance to bending/puncturing). In particular, you want the target to become liquid. No, this does not mean using a flamethrower or comic-book magic, but yes, it does mean creating a jet of hot metal. The chemical variety creates the jet at the point of penetration (c.f. HEAT rounds), while the kinetic variety provides the penetrating velocity right from the launch point (c.f. APFSDS shells).

Deployment

Since these are expensive weapons, you would generally not arm all infantry soldiers with them. However, if this was the only way to overcome enemy defenses, then you can rest assured that every army which could afford it would field such weapons as densely as necessary (say, one for every fire team or squad).

Countermeasures

This is why modern battle tanks use active armor: the only effective defense against such weapons is to trigger them before they actually come into contact with your armor, and try to deflect the jet. Obviously, by this point we are talking about something quite a bit more sophisticated than a glorified sandbag.

$\endgroup$
2
$\begingroup$

Why not use futuristic pavise ballistic shields for protection?

Because you'd be vulnerable to artillery, bombers and anti-armor weaponry. Your main advantage as infantry is moving fast and staying low. The shield negates both of these. It makes you vulnerable to the same things as armored vehicles, without the superior protection and other advantages of armored vehicles. In fact, the pavise shield can be thought of as a very primitive, human-powered armored "vehicle". It doesn't provide good protection for its weight, has little added firepower and poor mobility.

You could dramatically improve the armor, add a heavy gun that is affixed to the "shield", and add propulsion to make it move faster than an infantryman could carry it. Then you would pretty much get a modern light armored vehicle.

$\endgroup$
2
$\begingroup$

Modern warfare is about the fact that a man-portable weapon can kill someone in man-portable body armor.

In the short term, your shield can protect against someone using non-military weapons. If it is light enough to carry, military weapons will penetrate it.

The penetration distance of a newtonian impactor is proportional to the ratio of mass and the depth of the bullet. A bullet can easily be made to be pretty long and relatively dense; your shield basically has to be bullet dense and bullet deep to fully shield the person behind it; if you want to protect 1 m^2, and bullets are 0.5 cm^2 cross-section, it must weigh about 20000x what a bullet does (ignoring propellant).

A soldier carrying 100 bullets can carry heavier bullets than your shield can protect from, given the same carrying capacity. If you have an exoskelliton that lets you carry a heavy shield? They can have an exoskelliton that lets them carry and shoot bullets that go through the heavy shield.

The ground, sand bags, buildings and the like are things you don't have to carry. They can easily have huge effective depths and soak up weapons fire without having them to be man-portable.

In response, attackers can set up heavy weapons. Weapons that aren't man (or exo-suit) portable, require set up, and can in turn blast through the fortification you are hiding behind.

This results in a red queen's race. One solution (or local optima) is WW1 trench warfare, which was a stalemate because (in simplification) the attackers could win against the front lines, but couldn't carry heavy weapons to defend their advances. So you would (at huge cost) overrun the front lines, then you'd be destroyed in a counter attack (as the enemy heavy weapons are in place, and you don't have any on your side). And repeat.

WW1 trench warfare gets beaten by mechanized troops, heavy weapons, tanks, airplane support, and modern fire-and-cover tactics to exploit breakthroughs.

Nuclear weapons make a continent-wide battle seem unlikely; less extreme combat tends to be more mobile and less total. Modern fire-and-cover tactics using mechanized forces that the USA uses relies on real time intel and the availability of unlimited range unlimited firepower support.

Your light mechanized troops advance until they hit resistance, then fall back locally, call down the thunder, then continue. The troops are armored against much human-portable firearms (in their mechanized infantry devices). They become vulnerable against human-portable anti-armor weaponry and static explosives (IEDs).

In towns, especially with civilian population, this doesn't work. Now, an asymmetrical situation where attackers using exo-suits heavily enough armored to defeat enemy most small-arms fire could develop, making in-city fighting mirror desert storm.

This is half way between police action and military action; when you are attempting to kill the enemy, but not the person standing next to them.

So, if your world has a dominant military power, their troops might use exo-suits that are armored against small-caliber fire (hunting weapons etc) and carry heavier ballistic shields (which can soak AK-47 scale fire). They would in turn carry a mixture of anti-personnel, anti-suit and anti-armor weapons.

Anti-suit weapons would have the problem of blowing through buildings (causing collateral damage) and the ammo would be much heavier. Anti-personnel rounds would be much lighter and would be less likely to kill people a few km away. And anti-armor would a speciality weapon.

The shields would be used by SWAT teams and military involved in asymmetrical police action, where most of the enemy is armed with obsolete weapons only. In a symmetrical fight, the shields would be mostly useless and discarded, as anti-suit weaponry would blow through the shield.

A suit carrying an armor-grade shield would be ridiculously slow and could be taken out by flanking or using anti-armor weapons anyhow.

Armor-grade troops -- whatever the analogy of tanks -- would be immune to suit and personnel-grade weapons, resistant to anti-armor weapons, carry ridiculous cannons that can penetrate enemy armor reliably, and act as light mobile artillery.

The thing is, suits are probably a bad anti-personnel weapon at this stage. Light unmanned drones with anti-personnel weaponry would be cheaper and smaller than anything you could wrap around a human. Suit armor would basically scale with what is required to survive attacks by such drones (as even insurgents could probably build hunter-killer drones).

$\endgroup$
1
$\begingroup$

Your shields provide defense against direct fire. But don’t provide protection against explosives. The shock wave of an explosion is the killer. For your shields, assuming they aren’t throw by the detonation, only deflect a portion of the energy.

Where sand bags and similar defenses a absorb and attenuate the shockwave.

Soldiers seek out natural shields when they advance on a target by using natural cover like rocks, trees and the rolls of the earth.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.