Stavatti TIS-1 (Tactical Infantry System-1) Gasdynamic Laser Weapon

[rogermccarthy]

SF writer Charlie Stross has this quote from Defence Review on his blog (http://www.antipope.org/charlie/blog-static/2007/03/anachronisms.html):

a "white paper" proposal that was submitted to the U.S. Army for the Stavatti TIS-1 (Tactical Infantry System-1) Gasdynamic Laser Weapon. The TIS-1 is a laser rifle that utilizes a hypersonic jet of gas to create photonic energy in the form a very powerful laser. Thus the term "gasdynamic". The Stavatti TIS-1 was submitted as a possible technology for the U.S. Army's LFLAN requirement. "LFLAN" stands for "Light Fighter Lethality After Next". LFLAN involves small arms technology proposals that would not be implemented until 15-25 years down the road. In other words, truly futuristic technology.

[end DR quote - Charlie's comments next]

The laser itself looks pretty reasonable, in an if-we're-talking-about-laser-weapons way ("laser" and "weapon" belonging in the same sentence in the same way as "automobile" and "rubber-band powered"), but the power supply is what makes this one special. In search of the ultimate in infantry-portable enemy-slaying goodness, Stavatti have one-upped all previous attempts by proposing to use a radioisotope generator containing 750 grams of Polonium-210. This would, of course, provide the necessary 100 kilowatts to power the man-portable death ray. It would also provide 125 petaBecquerels of radiation (as compared with the 100 pB of Cesium-137 spewed out by the B reactor at Chernobyl), and the need to pressurize it to 4000psi leads me to agree with my military informant's summary that "it might actually achieve the near-impossible feat of making Project PLUTO look environmentally benign by comparison."

I will also confess that my suspension of disbelief took a slight knock when I got to the bit about the TIS-1 also sporting a bayonet lug.

Anyway, I'd just like to say that I fervently hope the Pentagon's planning and procurement folks give this proposal the attention it undoubtedly deserves. As Polonium-210 is accounted for (when you can buy it) at a market price of roughly $12 million per gram, this weapon system will cost roughly $54Bn per rifle per year to run — the US Army could afford almost an entire squad, and thus might have to scale back their other projects accordingly.

(PS: 100 kilowatts is, in automobile terms, about 130 horsepower. So if you were to ditch the Dr Strangelove power supply the gadget could plausibly be mounted on a HMMV or Land Rover. But I find that idea somewhat disappointing ... and anyway, what would be the point of sticking a bayonet on a vehicle-mounted laser cannon?)

[end Charlie's comment].

Any views?

 

[selunatic2397]

I think this sounds like something my player "Mr. Wizard" would come up with....

By the way...He's still working on his manportable 1 MW beam laser...

Nothing is worse than a determined munchkin.

 

[mbrinkhues]

Man-portable: In military parlance the equivalent of "somebody welded a handgrip on it and/or made it splitabel in parts and it can be transported by 2-3 humands without a forklift over long distances".

Like the 60 and 81mm "man portable" mortars or the MILAN ATGM....

 

[Uncle Bob]

Hmm, solid-state (LED pumped) lasers are near-term. IIRC, there was one deployed last year as an anti-IED device. That implies 10kw+ and it was mounted in a HMMWV.

 

[Todg]

A man porpable laser still doesn't really offer much in improvement over projectile weapons. It still suuffers from having linear danger space, which means that it can't defeat intervening cover.

This is the reason the military is interested in things like smart projectiles (XM-25) that have an area effect and can be used on targets behind cover. It also compensates for aiming errors, which a laser does not.

Lasers rifles are a neat idea from science fiction, but don't really offer any significant advantages over conventional weapons when it comes to real combat - unless the power gets really high. And that will create other issues.

 

[Blue Ghost]

I think the Stavatti was shown to be a pracical joke; i.e. not a real proposal, or so I recall. From what I recall it's been discussed on this board in years past.

 

[Andrew Boulton]

Originally posted by Corejob:
A man porpable laser still doesn't really offer much in improvement over projectile weapons.

No moving parts, flat trajectory/zero flight time, no muzzle flash/sound. A good sniper's weapon, perhaps.

 

[Anthony]

Realistic laser weapons have all sorts of problems, which generally make their role (other than blinding weapons) rather limited.

A penetrating wound with a laser weapon (something to get immediate lethality) requires on the order of 100 kJ/cm^2 if you're simply burning through flesh, somewhat less if you're using a train of steam explosions to clear the path. Either way, you probably want a 1-2mm spot with a discharge energy of 1+ kilojoules. If delivered properly, that will have lethality on a level with a conventional firearm (if for some reason laser energy is very cheap, you can use more power in a bigger spot size, but it's fairly wasteful).

A 500 nm visible light laser with a 150mm lens (which is not small, if you've ever used a 150mm telephoto) can focus down to a 1cm point at a range of 150m. It will also be visible to the naked eye, due to scattering off of atmosphere. A 1 micron IR laser would be nearly invisible but has half the range.

Within that range, it does have some advantages: specifically, you have no measurable time of flight, and your crosshairs can easily show you exactly what you're going to hit (you can basically have a SLR laser rifle). It also has a side benefit of being a 6" telescope. All of this might have some applications to, say, police work. As a military weapon, it seems very limited.

 

[Straybow]

So, perhaps using UV wavelengths and a little TL10+ handwaving you could get focus down to 1mm at 1000m+. Added bonus: scattering photons are not visible to the naked eye.

Vehicle mounted weapons can make use of very large aperature emitters to minimize diffraction of the beam. For man-portable weapons using a tripod mount you can get away with a rather bulky emitter.

You simply aren't going to end up with a sleek, pulp fiction "rifle."