Sand as a weapon?

[ravells]

From here
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Sand would be an excellent weapon to use in outer space.

On board a spacecraft? Select the most delicate piece of machinery you can find and throw a handful of sand into the works. They'll never get it all out, never ever.

Fighting another ship? Lob a missile full of sand on an approximate intercept course and have it detonate halfway. Detecting and avoiding a grain of sand at a thousand kilometres' distance? Impossible. Odds of being hit by at least one grain while passing through the region? Near certainty. Destruction caused by collision with a single grain at several hundred km/s relative speed? Total.

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If this is correct (and I don't know enough physics / mechanics to know if it is) then those sandcasters might be quite good offensive weapons? Would sand also be able to stop a missile?

 

[aramis]

assuming a grain size of 0.1mm, SG=5, that's 0.000001g, so the 6G-turns of acceleration of 1500s =1500x60=90000m/s, and mv^2=8100J - about a large caliber rifle bullet. (slightly better penetration, due to smaller size)

Now, assuming spreading them to cover a 100km square (a tiny bit of a hex)... and using the 20kg of capacity typical per SS3... that's 20E9=2E10 pieces. in 1E10 square meters. 1 grain per 5 square meters. If you need to hit the covered space of a single hex...
1500^2=(150+75)E4=225E4=2.25E6 per side; going square, that's (2.25*2.25)E12=(4.5+.45+.1125)E12=2.0625E12 square meters... or one grain per 2.06E12/2E10=(2.06/2)E(12-10)=1.03E2... 1 per 103 square meters...

Not really enough to do much damage to a ship. that's a rifle bullet per 10m square of cross section.

Now, in countermissile fire, yes, that sand, if it can be dumped into a smaller area, say, 1km on a side, (1E6 sq meters... 1E6/2E10=0.5E-4=5E-5= 0.0005m^2... or 1 per 5 square cm... still not an assured hit, but close enough. Fired at an incoming missile, this means probably getting 2-10 hits, as if by a big rifle.

So, plausible anti-missile? yes, barely. Plausible anti-ship? no. Note that a similar hit on the Shuttle, at orbital velocity, merely chipped a windshield and startled a crewman.

 

[ravells]

Thanks Aramis. The way I saw it, ships are probably micro-meteorite proof anyway in which case a grain of sand would not present a problem.

 

[sabredog]

In High Guard sand canister fire is on par with lasers for anti-missile defense. It might be in Mayday, but I think it was in the first edition of LBB2 also that sand helped intercept missiles, but there wasn't a -DM per se since in LBB2 combat is resolved with tracking vectors and intercepts.

 

[Selandia]

got my mind going

"minefield": 500,000 bulk carrier that loose its cargo of 400,000 t dwt. Said cargo is made of 100,000 boulders of approx 4 t. Of course, to acheive an interesting density, the field would be small and therefore spread on something like the known orbital trajectory of a Starbase. Of course some will try to just use the bulker as kamikaze but raming is an other discussion.

Selandia

 

[aramis]

got my mind going

"minefield": 500,000 bulk carrier that loose its cargo of 400,000 t dwt. Said cargo is made of 100,000 boulders of approx 4 t. Of course, to acheive an interesting density, the field would be small and therefore spread on something like the known orbital trajectory of a Starbase. Of course some will try to just use the bulker as kamikaze but raming is an other discussion.

Selandia

That would be roughly 80kTd of cargo space - we've not seen any canonical designs with that kind of hold space. Still, the spread numbers make that less than improbable to avoid.

 

[Dragoner]

On board a spacecraft? Select the most delicate piece of machinery you can find and throw a handful of sand into the works. They'll never get it all out, never ever.

Two words: compressed air.

 

[Carlobrand]

Sand would be an excellent weapon to use in outer space.

On board a spacecraft? Select the most delicate piece of machinery you can find and throw a handful of sand into the works. They'll never get it all out, never ever. ...

Uh, why are the people operating the ship giving you access to the guts of their delicate machinery? It's a bit like saying you can bring down an airplane by tossing sand in sensitive equipment. You are either: 1) a hostile invader, or 2) there at their consent (crew, passenger, etc.). If 1, then it seems to me that if you've got that kind of access you can find a lot worse things to do than running around tossing sand in things. If 2, then you might want to consider the wisdom of throwing sand in the machinery of a ship that you're currently riding in - and, unless you're crew, you've still got the question of how to get access to the guts of delicate machinery.

It's not like every Joe Passenger's going to have unrestricted access to the bridge or the drive room. If you DID land a position that gave you unrestricted access, then it isn't just the sand that's damaging; it's your ability to penetrate their security arrangements. Without that, the sand is harmless.

As to the latter claim - you do understand we're talking about a futuristic vessel in a zero-g environment that has the technology to simulate gravity fields? Turn off the gravity and employ vacuums or pressurized air; manipulate the gravity field and compel the sand to fall "up", or sideways, or any other desired direction; send in nanobots to find and retrieve the individual sand grains; or just replace the affected part.

 

[saundby]

Actual strikes:
http://www.nasaspaceflight.com/2012/06/cupola-minor-mmod-strike-shutter-closed-evaluations/

As Aramis says, it's an annoyance, not "Total Destruction."

It's part of routine design to deal with debris of this sort..

There are also ways to defend against it if you know/suspect it to be there. And as to detectability, you don't have to detect one grain, you detect the presence of many grains through an area. Lidar scan would turn it up in a heartbeat.

An abrasive warhead is a possibility, there are complications to it, but it's an idea that's been kicked around IRL. But it wouldn't simply distribute a field and let it hang there, it would put it on target in a relatively small area.

 

[aramis]

pretty much anything but internal doors, air and water filtration is going to be pretty much sealed when not under active maintenance. And air and water systems will be designed for particulate capture.

And, few, if any, Traveller ships will be spending much time in 0-G except for TL 8 & 9 designs (where there's no AG/IC systems) or seriously alternate ATU's.

Even then, a hand vacuum and some time under acceleration, and any sand thrown about is easily settled and sucked up.

In microgravity, fluid corrosives are much more a threat than sand (tho' silicosis is a long-term issue from sand in hab spaces). In part because it will eventually hit something, and it will only spread on the surface if it's on the "down" face during accelerations.

 

[Hyphen]

To round things off, under HG, MT & Striker, sandcasters can be used as a weapon against _ground_ targets.

"Sandcasters may be used as a sort of giant shotgun. They have a diverging danger space (or "footprint"): C=1m; S=1.5m; M=4.5m; L=24m; VL=48m; D=90m; 2km=120m."

Pen 20/2, Dam 10 (MT stats).

 

[Burocrate]

Type S Scout VS TL 5 Steam Ship

My Referee knew of this 'shot gun' use of sand against ground targets and ran with it when my Pilot tried to run off an ocean vessel that was attacking another ocean going vessel when

Lessons learned:
1. Have the skill you are using if you want to succeed (Pilot did not have Gunnery)
2. Stock more than one re-load if you intend to fire your weapons
3. Sand canisters do bad things to unarmored personnel on the open deck of an ocean freighter

 

[aramis]

Let's see... a 50kg container per "sand" shot.

Silica is SG 2.65 or so... we'll use SG 2.7, for the trace whatever...

So, that's 2.65 g/cc for 18868cc (~18.9L) ÷ 0.7 (packing efficiency) ~25954cc - 26L

Per 26L, 50KG canister, spherical particles
At 0.1mm particles, that's 3.6E10 spheres 3.4E-7 g each (0.3µg)
at 0.5mm, 2.9E8 particles (290M), 1.7E-4g each (0.17mg)
at 1mm, 3.6E7 particles (36M), 1.4E-3 g each (1.4mg)
at 3mm, 1.3E6 particles(1.3M), 3.8E-2 g each (38mg)
at 5mm, 2.9E5 particles (290K), 1.8E-1g each (0.176g)
at 1cm, 3.6E4 particles(36K), 11g each

Just some numbers for y'all to play with.

 

[Selandia]

If "sand" canister were intended to be used against infantry, the specific "anti-personnel" canister loaded for the task would likely be designed not as the Shaff pod that come to mind when thinking Sandcaster, but as something intended to cause harm as its main effect (rather than as a welcome colateral damage). Likely either as a flechettes (real shotgun effect) or air bursting shells. While Shrapnells shell went out of fashion when properly fragmenting High Explosive shell with reliable time fuze became available, it is possible (to contrive something that preserve the shotgun like zone of efficiency) that a "flying shotgun shell" reminescent of the Shrapnell might be in use in that TU.

Selandia

 

[aramis]

If "sand" canister were intended to be used against infantry, the specific "anti-personnel" canister loaded for the task would likely be designed not as the Shaff pod that come to mind when thinking Sandcaster, but as something intended to cause harm as its main effect (rather than as a welcome colateral damage). Likely either as a flechettes (real shotgun effect) or air bursting shells. While Shrapnells shell went out of fashion when properly fragmenting High Explosive shell with reliable time fuze became available, it is possible (to contrive something that preserve the shotgun like zone of efficiency) that a "flying shotgun shell" reminescent of the Shrapnell might be in use in that TU.

Selandia

Real shotgun shells nominally use literal round balls as the default; flechettes are not used that much. (They tend to have better penetration, but you get FAR fewer of them in the round.) Solid slug is also available. (So also are HEAP, tear gas, flare, and even "dragon" rounds - powdered magnesium incendiary "flame thrower.")

 

[Spinward Scout]

Oooh, I like this. Just think if a ship is surrounded by sand when a missile detonates, would the people/ship take damage from both the missile and the sand?

 

[jappel]

I seem to recall someone (Mssr. Whipsnade, perhaps?) mentioning the use of sandcasters to great effect in the Chamax Plague.

 

[aramis]

Oooh, I like this. Just think if a ship is surrounded by sand when a missile detonates, would the people/ship take damage from both the missile and the sand?

Missile? Yes.

Sand? Not much, if at all. There's very little shockwave. Sure, you get a VERY fast moving wall of gas - but it's rapidly losing density. Some of it is slowing down due to backpressure from the front, some is pushing forward...

As the pressure in the sphere drops, so does its ability to push the sand. Likewise, the pressure is moving that gas pretty damned fast, so there isn't much time to act on the sand and accelerate it.

The sand close enough to be pushed is mostly going to be moving in the wrong direction - the warhead needs to be pretty close to do much of anything.

Even in atmosphere, missiles have to be right close to do much. without the Atmosphere to carry the shockwave, the explosives have far less impact at distance.

 

[ShapeShifter]

Moving up in scale, to, say, marble sized, and if one were to pack enough into a missile -- vaguely similar the 7YW/Nap canister rounds for howitzers -- I'd imagine that they would really be more effective. Now all I have to do is get those little buggers up to near-c. Then, goodbye cozy environment, hello hard vacuum.

 

[aramis]

Moving up in scale, to, say, marble sized, and if one were to pack enough into a missile -- vaguely similar the 7YW/Nap canister rounds for howitzers -- I'd imagine that they would really be more effective. Now all I have to do is get those little buggers up to near-c. Then, goodbye cozy environment, hello hard vacuum.

3 G-Hours should do nicely - 108000sec at 10m/s/s= 1.08E6 m/s

Given E=MV^2 ...
1.08*1.08=1.16E12*Mass Joules

So those 1cm spheres, at 1.4G each (I misplaced a decimal before) hit 1.64E12J - roughly 0.4kilotons each.

This is why we don't want to go burning away for too long - a single little rock like this can do serious damage to a high-speed craft.

that's also 3.8E9m/hr, or 3.8E6km/hour - 3,888,000km/hour or 0.026 AU/hour - or 1 AU every 1d14:28:37

Mars would be 4 days away at that speed right now... and each bit of silica buckshot is a carbomb's worth of explosive force.

Oh, and they're small enough that, even at that speed, they're gonna be glowing streaks, not imactors, should you smack a habitable world.