When missiles and bullets COLLIDE!, A question for people who know guns Options

[nezumi]

Alright, a quick question I'm not sure how to address...

A player plans on spraying a GMC banshee with his ingram valiant (loading EX Explosive rounds). Knowing the banshee is armored to no end (how does something with that much armor fly again??), he's calling shots on the front turret and the side loaded missiles.

So what happens when a missile or rocket (or grenade, for that matter) is sprayed with automatic fire, especially when using explosive bullets? I assume missiles have something to prevent them from going off accidentally, which means they're inert until active. I also assume the missile doesn't have any ammo worth mentioning. So the bullet spray would simply destroy tracking computers and firing pins in the nose of the missile, and otherwise make it non-aerodynamic and unworthy of flight. This means that, with sufficient machine gun fire, all the missiles will be incapacitated and the t-bird will be left with the nose turret only, but will otherwise be largely safe from anything the gunner might attempt to do.

Thoughts or comments on this? Am I completely misunderstanding the nature of explosives?

[Foreigner]

nezumi:

Others will probably contradict me but, as I understand it, you are essentially correct.

Missiles and bombs are THEORETICALLY inert if they haven't been armed.

However, there's always a possibility that the proverbial "lucky shot" might hit a bomb's/missile's detonator, which could trigger the explosive charge even if the weapon itself hasn't been armed.

Another possibility would be damaging the parent vehicle through intense heat, which might happen if a missile's fuel supply was compromised by a bullet--some rocket fuels start to burn if they come into contact with the air, or if the separate fuel and oxidizer compounds come into direct contact with each other anywhere outside of the controlled environment of the missile's fuel intermix chamber.

For example, several Iraqi SS-1 "Scud" missiles were destroyed by long-range precision rifle fire, using Barrett M107 .50 BMG rifles, during the First Gulf War. The fuel and oxidizer combination used in those weapons is VERY unstable. What happened was that U.S. and Coalition snipers punched several holes in each missile at strategic points--in and around the fuel tanks.

When the chemicals involved in the fueling process mixed, they burst into flame, causing the missile to burn/explode, and most likely destroying ancillary equipment, such as the missile launcher truck, the fuel truck, and the vehicle carrying the control equipment.

Let's face it; when you're dealing with a missile that's roughly the size of an average municipal cell-phone tower (the SS-1 was basically a two-stage V-2, developed using captured German (World War II) technology), a few one-half-inch-diameter holes aren't going to be noticed, unless you have the time to do a REALLY thorough inspection.

Food for thought. :)

--Foreigner

This post has been edited by Foreigner: Jul 3 2006, 11:23 PM

[hyzmarca]

There is no such thing as an explosive that is completely inert, the conditions of being explosive and being inert are mutually exclusive. The actual probability of an missile being prematurely detonated by a bullet depends very much on the design of the missile itself. There are so many different types of missiles that it is isn't possible to give a single answer that would be true in all cases.

[Frag-o Delux]

Most portable missiles from what I have read use solid state engines, basically a solid stick of fuel in the tube of the missile body. Only really huge rockets/missles like ICBMs and possibley Scud type missiles use liquid fueled engines. I dont know the cook off temperature or how voilitale these fuels are for the solid state fuels, I have to suspect they have been made to resist accidently cooking off from incoming fire. Solid state engines can and do cook off, but not nearly as easily as liquid fuled engines.

Most high level exsplosives, such as the ones used in warheads are made of pretty robust chemicals like RDX, which need a smaller explosion to make go off. From reading, RDX is pretty hard to set off on its own, so you need a much easier to detonate explosive to set them off such as nitrocellulose. Not arming the missile is to keep these easier to detonate fuses from accidently setting off the much more powerful explosive.

Missiles are generally made "unsafe" before the platform takes them out into combat, but they still arent armed. They dont arm till the weapon is designed to arm them, sometimes in mid flight, sometimes just before impact.

Either way, shooting at a stack of missiles may not give the desired effect of blowing the roof off a Banshee, but there is certainly a cook off factor.

In fact even if he does set off the warhead chances are itll still do nothing. High exsplosive missiles and rockets will generally just go around a heavy armored vehicle. Were anti vehicle weapons need to hit pretty close to nose to body like a 90 dgree impact, to work since theyll be using a shaped charged warhead to penatrate the vehicles armor. Since the missile is on the mount and not aimed directlly at the Banshees the molten core of the AP missle will shoot off into nowhere (well not nowhere, but not at the Banshee.)

But thats my take on missiles and my limited research in missiles and rockets.

EDIT: It maybe in better interest for your friend to shoot at the parascopes an other viewing/sensor equipment to blind the tank.

[Kagetenshi]

[mfb]

many missiles use explosives that require detonation to go off--eg, a blasting cap, or hot lead smashing into it. C-4, for instance, can generally be lit on fire or stomped on with no explosion, but not both. so, while i'd generally rate the probability of a missile exploding because you shot it as low, it's not impossible.

[Edward]

It occurs to me that the EX Explosive ammunition may be sufficient to detonate relatively stable explososives (such as those used in weapon warheads) where other ammunition would almost certainly fail.

Edward

[Ryu]

ExEx:
That would depend on the speed of the shrapnel, as the explosion would not occur "inside" the warhead. Only the kinetic energy of the shrapnel might cause the explosion (a missile trigger should only arm after a few meters of flight).

A massive bullet fired at a right angle to the surface of the warhead should fare better.

[Birdy]

It is far easier to disable a missile than to explode it.

A hole through the solid fuel engine will give the gases an other way to escape, changing the trust balance and send the missile of on a wild trajectory. A hole through a fuel tank that uses either very cold or quite agressiv fuel is not something that can be easily patched on the spot.

As for "cooking off" a missile: The propellant charge of tank canons can and do explode if hit be the jet of a HEAT round. That is actually the main damage mechanism of the beast (The hole punched is rather small). Bombs/Missiles on the other hand can be build to withstand a jet fuel fire for IIRC 15 minutes, i.e on a carrier. So chances are small that an ExEx will fire them of

And finally the missiles are most likely not "out in the open" but rather in transport/launch containers inside a starter with at least the barrier rating of sheet metal. Think M2 "Coke can" IFV with the external TOW launcher

[Austere Emancipa...]

[nezumi]

Thank you for the replies. So it sounds like, barring an absolutely awesome success, even EX Explosive ammo will not set off the rockets. It's good to be right now and again : )

As for the rockets being out of LOS, I'm going off the pictures like this:

http://static.flickr.com/77/179594055_3af4dab5ed.jpg

Where there are at least two obvious missiles. The Banshee is listed as "scout" sized vehicle, so I assumed there were no dedicated missile bays.

[Austere Emancipa...]

I believe Birdy meant having a rocket/missile launcher encased in light armor, like the one on the M2/M3 Bradley, seen here in firing mode and here disengaged. Such mounts are less common on aerial vehicles because aircraft are not normally expected to take withstand large significant amounts of non-armor piercing projectiles like ground vehicles are -- but the extremely heavy armor on Shadowrun "thunderbirds" imply quite different design principles, which might make the Bradley a more likely comparison.

[Foreigner]

A.E.:

I'm probably way off-base here, but i've always pictured a T-bird as similar in design and/or appearance to the dropship in ALIENS.

Am I anywhere close to being correct?

Pardon the brief OT excursion. :)

--Foreigner

[Austere Emancipa...]

They do share several characteristics: thick, rather unaerodynamic body, often of very blocky design, with short stubby wings. Of course the dropship is massive, and designed for different kind of flight than T-birds. I'm not familiar enough with any other aspects of the Aliens dropship to compare those, but the aesthetics are certainly similar.

[Frag-o Delux]

I think I seen a Banshee picture in one of the later 3rd edition books, but it seems no one knows what it looks like.

Sorry about the bad scans, but the Riggers Blackbook I have is really old and in rough shape, I was trying to be gentle with it.

GMC Banshee

And because it was on the next page over

CAS/GD "Stonewall" MBT

[Rock]

There's a Banshee picture in SR1 page 131. It's the page with a Mitsubishi Nightsky as well and is a page behind the Eurocar Westwind 2000 (pg 130) and a page before the Yamaha Rapier (page 132).

I knew thumbing through my 1st Edition this morning would come in handy for something other than a trip down memory lane.

[nezumi]

Holy carp, that's it? Boy, it's awfully phallic shaped. So whats the little thingy I linked to? A baby?

[Frag-o Delux]

Yeah thats the Banshee, and I guess if you want to call it phallic shaped, you can, I mean it is meant to penetrat into opposing territory and possibly deliver troops.

The problem with a lot of art in SR is its made up. I know its all made up, but in general a lof of the vehicles in the art are not things described by the books. That picture you linked to could just as well be a LAV from a rival corp.

[ShadowDragon8685]

That art looks like they described Shadowrun to the Battletech art guy in about four sentances, gave him an additional sentance about the Banshee, and said "We need a picture of it in about ten hours. Good luck."

If you want a REAL vector-thrust aircraft, you can do no better than to look to the Pelican, from Halo.

http://www.france-fps.com/images/halo/pelican.png

[Frag-o Delux]

Well actually if you want to look at REAL vectored thrust vehicles youll have to look at the F35B and the AV-8B.

If you want to see another persons idea of what futuristic vector thrust vehicles will look like. Look at the Pelican.

[Birdy]

The "Hovertanks" from 2300AD are an other (and pre SR-1) example of Vector trust Armored fighting vehicles. Despite the Hover and the Skirts they are actually jet-driven using the skirt as an additional means of generating lift. Some Target practice for the germans can be seen here.

And there's always the original article the "Blowers" from David Drakes excellent "Hammer's Slammer's" universe. The second best tanks in existence. Right after the ones that introduce themselfs with words like "This is unit LNE of the Dinochrome Brigade"