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Pentagon: No more death rays

jec10

SOC-13
http://blog.wired.com/defense/2008/02/pentagon-report.html

The Defense Science Board, an influential advisory panel, has a new report on directed energy weapons that finally injects some realism into the laser debate. Instead of inflated, sci-fi-esque claims and giant laser projects, the Board wants to see a more measured tone -- and smaller, more practical applications for military energy weapons. "The Department needs a concerted education effort to replace the 'death ray' myth of directed weapons with a comprehensive understanding of the potential benefits and limitations of their applications."

This is realism, not pessimism, and the Defense Science Board has it right. They're not saying that a "death ray" is impossible, or that it will never happen, but that wildly unrealistic expectations for death rays may well have actually set back laser work in the Pentagon.

For those who closely follow the Pentagon's myriad laser efforts, much of what the panel says will come as little surprise. Chemical lasers, such as the one on the Airborne Laser, are still the only megawatt class beams around, which could be used to take out ballistic missiles. But there are serious drawbacks to the weapon, and enthusiasm in the Pentagon has declines for it. Solid-state lasers, which are being developed for use on Humvees and ground vehicles, and fiber lasers offer a promising alternative, but at lower power levels. Microwave weapons, in the meantime, have some interesting niche capabilities, such as disabling cars and electronics.

On the wonkier level, the report discusses the need for coordination of the various laser efforts, developing a coherent strategy for where and when lasers will be deployed, and protecting the diminishing U.S. industrial base for lasers.
 
<sarasm>
I fully expect the head of the DSB to be sacked any day now for trying to be too conservative with the defense of Our Great Nation©.
</sarcasm>
 
Interesting. Here's a link to another, somewhat related story on the US Navy's test of their railgun prototype.
 
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Interesting. Here's a link to another, somewhat related story on the US Navy's test of their railgun prototype.

Saw that yesterday. 10mj of power right now and 12 nautical miles, they say it has the capacity for up to 32mj and 200 nm. Very cool!
 
I was impressed by the still captures from the film. You can see the visual distortion caused by the air displacement around the slug as it approaches the target.

I guess it will take awhile before they can reduce it from building-sized to ship-sized then more time to get it down to tank turret-sized... but still cool.
 
I guess it will take awhile before they can reduce it from building-sized to ship-sized then more time to get it down to tank turret-sized... but still cool.

2020-2025 is the projected period in which they will be replacing the current 5 inch guns with these new railgun systems.
 
http://blog.wired.com/defense/2008/02/pentagon-report.html

For those who closely follow the Pentagon's myriad laser efforts, much of what the panel says will come as little surprise. Chemical lasers, such as the one on the Airborne Laser, are still the only megawatt class beams around, which could be used to take out ballistic missiles. But there are serious drawbacks to the weapon, and enthusiasm in the Pentagon has declines for it. Solid-state lasers, which are being developed for use on Humvees and ground vehicles, and fiber lasers offer a promising alternative, but at lower power levels. Microwave weapons, in the meantime, have some interesting niche capabilities, such as disabling cars and electronics.

On the wonkier level, the report discusses the need for coordination of the various laser efforts, developing a coherent strategy for where and when lasers will be deployed, and protecting the diminishing U.S. industrial base for lasers.

I smell disinformation.
 
I was impressed by the still captures from the film. You can see the visual distortion caused by the air displacement around the slug as it approaches the target.
I guess it will take awhile before they can reduce it from building-sized to ship-sized then more time to get it down to tank turret-sized... but still cool.

I can't remember where I saw it, but the US Army is working on railgun meets 120mm mortar. AFAIK, the big problem is having enough power on the vehicle.
 
The picture of the flames from the muzzle when fired and the comment of "lightning and thunder" tend to put the old Gauss guns are silent and invisible to the lie eh?

Granted the Traveller soldier's hand held Gauss Rifle or Gauss Pistol are nowhere near this powerful but, just like they will have recoil similar to their conventional arms cousins, so too will they likely have a similar associated muzzle flash and bang. Can we finally put to rest the myth of zero recoil, zero sound, and zero muzzle flash Gauss weapons in Traveller and just treat them as another firearm? One that needs electricity instead of powder to work and fires fast tiny bullets instead of slow big ones.

Of course in Traveller we DO have death rays so what the heck, maybe magic guns are ok too :smirk:
 
The flash/bang are caused by the hyper-velocity round heating the air through friction/shockwave compression effects.


Whether that will be as dramatic with an infantry rifle-sized projectile remains to be seen.
 
If you watch as they insert the round you can see a weight chalked on the side of it of something like 3.27kg, which looks about right given the size.

That's a tad larger than the rounds fired by a gauss pistol or rifle.
 
The anticipated range of the eventual design highlights the unfortunate mistake in CT/MT of making mass driver guns not have either increased range or increased penetration over ordinary CPR guns.
 
The anticipated range of the eventual design highlights the unfortunate mistake in CT/MT of making mass driver guns not have either increased range or increased penetration over ordinary CPR guns.

it seems to me that increased range and penetration is more a result of increased muzzle energy. CT/MT must assume mass drivers have same muzzle energies as comparable CPR guns and not allow for pumping higher energies into the round. Alas, I don't know of a good way to take that into account prior to FFS.
 
The flash/bang are caused by the hyper-velocity round heating the air through friction/shockwave compression effects.


Whether that will be as dramatic with an infantry rifle-sized projectile remains to be seen.

It is mostly caused by the plasma arc of the railgun. A coilgun would be much more subdued.
 
Re: U.S Navy Railgun testing
Reportedly, they've also been testing said weapon at a British Ministry of Defence test facility in Scotland....
 
Gauss Rifles simply don't put out the energy that these things do.

I don't think they've ever been considered recoil free. There is most likely some kind of report from a gauss rifle (a camera flash has a quiet report for example), but it's not as loud as, say, a 30-06. The majority of the sound from a GR would be the hypervelocity round cracking the sound barrier.

However, if you can tune the velocity down to around 1000FPS, then it should be not much louder than a air rifle.
 
Gauss Rifles simply don't put out the energy that these things do.

I fully realize that, hence my comparison to other personal firearms, which do use about the same energy. I never said that a Gauss rifle should sound like a howitzer.

I don't think they've ever been considered recoil free.

I'm sure this came up before and was answered more completely but iirc every rule set except TNE has treated them as insignificant or no recoil. All I have handy for cites are CT, MT and T20.

In MT they were Low recoil, meaning no zero-g penalty. Just like snub pistols and lasers, which were also the only ones in CT that had a reduced zero-g penalty. So one could argue that Gauss weapons are also low recoil in CT.

In T20 (which is CT for D20) Gauss weapons are listed as No recoil. So again the perception is that CT treats Gauss weapons as no recoil.

Oh, and Mongoose Traveller too, when I was following the development, started with (based on CT) that Gauss weapons had no recoil. I pointed out the fallacy there as well (maybe that's where the more complete answer was) and don't think I changed the developer's mind if they even noticed it.

There is most likely some kind of report from a gauss rifle...

That's all I'm saying, that they have significant felt recoil, that they make some noise, and that they probably have at least a small muzzle flash. While the long held perception and rule has been they are without significant (or any) recoil, completely silent, and have no visible flash.

However, if you can tune the velocity down to around 1000FPS, then it should be not much louder than a air rifle.

Sure, and with about the same armor penetrating ability, range, and damage. Only far less because the round itself is so light. Gauss weapons only work as well as they do because the rounds go so very fast.

But again, the perception and rules seem to be that Gauss weapons are "magic" and able to break the sci rule of sci-fi, in most of Traveller anyway, and I'd like to see that changed.

I will grant that a coil-rifle may well have less arc flash, but may have other problems to overcome.
 
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My (no doubt imperfect) understanding of the gauss rifle was that the slug being accelerated by magnetism rather than an explosion gave rise to a push rather than a kick, and hence the recoil was equivalent but more manageable.

Also, having no burning chemicals exiting the barrel, there should be no muzzle flash, unless the round exits so fast that it heats to incandescence?

I've always figured on a gauss slug being heavier than an airgun pellet (never weighed one) and having a hard core and soft jacket to increase penetration and damage, so even a slow needle should do more than pellet damage. This may be how gauss pistols work, but I agree gauss rifles should have high muzzle velocity, and will therefore be noisy.
Heading off at a tangent, maybe sound could be modified by needle aerodynamics and/or active sound suppression, where an inverse waveform is emitted simultaneously.
 
Re: Muzzle Flash
Some have argued that any muzzle flash, is due to the the round exiting so fast, the air around the muzzle briefly is turned to ionised plasma, due to compression heating caused by the shockwave the round creates...
 
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