Energy Shields - countermeasures

[SpaceMarine93]

We all know that in any popular science fiction series, whether it be set on Earth or in Space, there is one thing among many other things which the main characters cannot do without - Energy Shields. Whether it be Plasma shields, Deflector shields, Force Fields, etc. It is a McGuffin / Plot Device which allowed countless heroes or villains to be save from attacks that would had killed them and end the stories they are in immediately, especially in a world where practical laser and energy guns, powerful bombs and superweapons far more powerful than a nuke exists.

In the real world, attempts are being made to create force fields for a large varietiy of uses - In the University of Washington a group of researchers, in Seattle, has been experimenting with using a bubble of charged plasma to surround a spacecraft, contained by a fine mesh of superconducting wire. This would protect the spacecraft from interstellar radiation and some particles without needing physical shielding. While energy fields so far are still in research phrase and limited in capabilities, who knew how long when deflector shields become real?


So, here's the thing - I want anti-shield tech. I want to know what kinds of countermeasures had been thought up over the years to counter deflector shields, both in fiction and in real life. I want to know if there is some form of ultimate solution to bypass any deflector shields in fiction / real life

And even if this whole concept of deflector shields is ludicious in real life, just simply reflect on the basis of some form of technology / weapon that could pierce through any form of defense / protection on a spacecraft / armor / armored vehicle.

[Juubi Karakuchi]

It depends ultimately on your approach. There are shields, and there are shields.

Sci-fi 'shields' tend to be variations on the 'energy barrier' concept. The shield has a certain amount of energy running through it, which can be altered up to a point, and can be neutralized by the simple expedient of hitting it repeatedly with weapons of sufficient power. If a shield is visible, then it is loosing energy as visible light. A common trope is for a flash of light to pass over the shield from the point where it is struck, implying that the shield is redirecting the energy over itself. Dr Alderson's 'Langston Field' works on the principle of absorbing and radiating away the energy applied to it, (very) broadly fitting this model.

To penetrate such a shield, one must apply to it more energy than it can counter within a given space of time. For example, if a shield has ten units of energy running through it per second, then the application of ten units of energy in a single second will cancel it out. If the amount being applied is higher, then the remainder will leak through. The practicalities of this depend entirely on the technology involved. In the case of a one-piece bubble, then any fire applied to it from any direction will have the required effect. In the case of multiple smaller shields, then energy will have to be applied to a particular shield. This gives the enemy ship (assuming it is a ship) certain countermeasures, essentially moving itself in such a fashion that the shield in question cannot be fired upon consistently, similar to how an ICBM can reduce the effect of a laser by rolling.

There is an alternative to gaining local penetrations in this fashion. If one's weapons are insufficiently powerful to achieve a local penetration, or if one is unable to target a specific shield consistently, then an alternative is to keep on firing until the shield generators overheat or are otherwise exhausted. Once again this depends on the technology involved. It would only work if the ship was only able to keep the shield(s) up for a limited time, due to energy supply or overheating issues.

Another possibility lies in a 'shield-breaker', that is to say a missile or some other projectile that itself carries a shield. The idea is that the missile's shield will counter the defending shield, allowing the missile to pass through. If the shields are frequency-based (as in Star Trek and Dune), then the missile could be programmed to cycle through frequencies in the hope of matching the defending shield's frequency (180 degrees out of phase) and thus pass through effortlessly.

For what all that is worth.

[doom3607]

With frequency-based shields that have frequency-based interactions with frequency-based weapons, just fire off a few shots at several wildly different frequencies. The data you gather from the interactions caused by those shots ought to be enough to let your computers work our their sheild frequency, at which point they're screwed. Otherwise known as, presumeably, the Borg methodology.

[Whiskey144]

Another possibility lies in a 'shield-breaker', that is to say a missile or some other projectile that itself carries a shield. The idea is that the missile's shield will counter the defending shield, allowing the missile to pass through. If the shields are frequency-based (as in Star Trek and Dune), then the missile could be programmed to cycle through frequencies in the hope of matching the defending shield's frequency (180 degrees out of phase) and thus pass through effortlessly.

I'll note, however, that in Dune there isn't actually any reference to shield frequency. So a Dune-series shield penetrator would be moving slower than the shield's blocking threshold.

[doom3607]

Actually there is. The Harkonnens used layered shields all with the same frequency to keep slaves from leaving the arena, while they had personal shields with a frequency that let them just walk through. The term was pentashield, I think- the Dune book I had had a glossary at the back. If your does too, look it up.

[Whiskey144]

While I did find the glossary entry for pentashield, deriving "frequency" would reqire a somewhat strained interpretation of dissembler w/ shield codes.

I'd guess that the shield codes are transmitted by the dissembler, and tell the generator to let a person with the dissembler pass.

[doom3607]

Huh. Well, I didn't read it that recently.

[Simon_Jester]

Another possibility lies in a 'shield-breaker', that is to say a missile or some other projectile that itself carries a shield. The idea is that the missile's shield will counter the defending shield, allowing the missile to pass through. If the shields are frequency-based (as in Star Trek and Dune), then the missile could be programmed to cycle through frequencies in the hope of matching the defending shield's frequency (180 degrees out of phase) and thus pass through effortlessly.

I'll note, however, that in Dune there isn't actually any reference to shield frequency. So a Dune-series shield penetrator would be moving slower than the shield's blocking threshold.

...I didn't write that. Or anything else in this thread, until now.

So much depends on mechanism that this question is unanswerable. Do shields have a minimum velocity threshold, below which they block nothing or block unreliably (Dune)? A maximum velocity threshold, above which they block nothing or block unreliably (Honorverse radiation shielding)? Do they take the form of some static field of force which affects certain types of matter but not others (an electromagnetic field won't do squat to stop a neutron beam, if you can figure out a way to generate one)? Is this field of force 'static,' with no time-dependency in its strength, or is it 'dynamic,' with time-dependency in some cyclic fashion that opens up the possibility of frequency or resonance exploits?

Since "deflector shield" isn't a well defined technology in the sense that "coilgun" is, it's hard to say what counters to it might exist. Even if we don't have useful weaponized coilguns, we know roughly what they'd do and therefore how to stop them from doing it. The same is not true of "deflector shields."

[doom3607]

I thought Honorverse radiation shielding just got overwhelmed by the sheer amount of radiation they hit at over .8c.

[Simon_Jester]

I thought Honorverse radiation shielding just got overwhelmed by the sheer amount of radiation they hit at over .8c.

Do the math on radiation flux from flying through interplanetary space at .9c; it works out to something like 500 kW per square meter of the ship's bow.

That's bad, very bad by modern standards, but it's not totally unmanageable- and the ability of ships to fly through hyperspace, with its higher particle densities, at speeds of .7c or so, suggests that the intensity isn't really the dominating factor.

If it were, top practical speed would be controlled by distance from the primary and local conditions; some bits of space have more hydrogen atoms per cubic centimeter than others.

The fact that there's such a sharp, well-defined cutoff speed for ships whose shielding must protect them from being damaged by radiation exposure suggests, to me at least, that there's a speed cap: that the radiation shields are quite effective against even a relatively intense flux of charged particles at .8c, but of only limited value against charged particles at .9c.

I can think of a number of reasons why this might be true. Maybe I'm wrong according to Weber, but I feel it's about as sound an explanation of his ships' performance envelope as we're likely to see, with a relative minimum of technobabble.

[Whiskey144]

...I didn't write that. Or anything else in this thread, until now.

My bad. I think I confused the guy who did write it with you, by virtue of intending to quote something you wrote in another thread.

[doom3607]

Do the math on radiation flux from flying through interplanetary space at .9c; it works out to something like 500 kW per square meter of the ship's bow.

Because of course grade 11 physics is enough for me to be perfectly able to do that.

[Simon_Jester]

Actually, it is. You can at least get within shouting distance of a right answer if you care enough.

As an exercise for the student ( ), why don't you try to come up with a method for solving the problem? Where would you begin, what numbers or variables would you need to know, things like that?

[doom3607]

I got a seventy-seven becuase I didn't pay too much attention. And the only stuff on radiation we covered is that it disperses acording to an inverse square law and a couple types of the stuff.

[Ahriman238]

Well, there a large number of fictional shield types, each with it's own limitations, which could be curcumvented in a number of ways. Some are magnetic, or use cold plasma, many are Langston Fields that absorb and disperse large quantities of energy but can be brought down if the rate of incoming energey exceeds dispersal rates, and a fair few are powered by "fuck knows!"

Atomic Rocket has a pretty good summary on the harder side of things:
http://www.projectrho.com/rocket/spacewardefense.php

Aside from battering your way in or finding shield frequencies, you can employ 'smart' projectiles that will move slowly enough to penetrate the shield and then drastically speed up. Or specialized weapons that use an exotic particle/energy the enemies shields will not defend against, or focus much brute power on a relatively small point to drill through.

One idea that has always appealed to me is the "skipper." a missile (or starfighter) that bypasses a shield with an FTL micro-jump. See "Mutineer's Moon" by David Weber or "Fallen" (SG-1 Season 7, episode 1) for more.

If momentum is conserved, throw something very big, very fast or ideally both at it.

[doom3607]

Ah, Mutineer's Moon...

So Dahak's hiding on the moon?
No. Dahak is your moon.

And the third book said they had ~10 million planetoid-class ships before they all died... And they were 25% bigger than Dahak. Methinks even the GE would stand no chance at all, even though Fourth Empire ships can only pull a couple thousand c.

[Ahriman238]

So Dahak's hiding on the moon?
No. Dahak is your moon.

And the third book said they had ~10 million planetoid-class ships before they all died... And they were 25% bigger than Dahak. Methinks even the GE would stand no chance at all, even though Fourth Empire ships can only pull a couple thousand c.

The 2nd book, I believe. And ~200 million.

[avatarxprime]

One idea that has always appealed to me is the "skipper." a missile (or starfighter) that bypasses a shield with an FTL micro-jump. See "Mutineer's Moon" by David Weber or "Fallen" (SG-1 Season 7, episode 1) for more.

If momentum is conserved, throw something very big, very fast or ideally both at it.

Along those lines also exist any kind of teleportation based weapon. The best way to deal with a shield is to just ignore it. Whether that means teleporting beam shots into cockpits ala Turn A Gundam or using alternate dimensions like the Culture. This would of course force a new kind of arms race where you need standard shields to actually protect against weapons and then other defenses that ensure that the weapons hit your shield in the first place.

[Eleventh Century Remnant]

What about the closest thing we have to real world shielding? This is a BAE press release;

BAE Systems achieved an industry first in February 2005 by successfully defeating incoming threats during live-fire testing of an Electromagnetic Armor (EMA) package fully integrated onto a hybrid-electric drive combat vehicle demonstrator.

This effort, using an EMA package fully integrated with the hybrid-electric drive system, was accomplished through a Cooperative Research and Development Agreement with the U.S. Army Research Laboratory and the Army's Tank Automotive Research Development and Engineering Center (TARDEC) in Warren, Mich.

The successful completion of live-fire testing of an EMA package on a hybrid-electric vehicle demonstrator illustrates the type of multi-hit capability that can be integrated into vehicle systems at significantly lower weight to provide a level of protection similar to reactive packages.

The EMA package successfully defeated a shaped-charge threat during live-fire testing earlier this year at Aberdeen Proving Ground in Maryland.

EMA technology can significantly enhance the survivability of vehicle systems as part of a layered approach ultimately aimed at increasing soldier protection.

EMA uses electricity to defeat shaped charge warheads such as those from Rocket Propelled Grenades (RPGs).

Research in reliable power management and delivery at lower volumes and weights for Pulse Forming Networks (PFNs) allows the system level integration, experimentation and demonstration of EMA on a combat vehicle.

I've quoted essentially all of it, but http://www.baesystems.com/ProductsServi ... armor.html anyway. Not sure whether the program still exists, but if it does then there is shielding just round the corner.

Of course, there's always the other definition- planks at right angles, rawhide rim, steel dome to protect your hand and punch grip, painted in group or unit colours. In both cases the solution may be the same- just hit it harder.