Explosive Firearms Cargopods

[SandJ]

Usually, if I scoop a cargo pod with illegal goods in it, I just jettison it again. I actually shoot the cargo pod if it contains firearms or drugs.

That sounds dangerous. If a one tonne cargopod contains 500Kg of TNT, the save standoff distance on Earth is 125m when in a building or 550m when outdoors.

(Project ECHELON now has some interesting data on me based on the search results I went through trying to find that information.)

So that gets me thinking, you don't want to be too near an exploding firearms cargopod - it might go BOOM!

Assuming Elite-era explosives give more bang per buck kaboom per Credit than TNT, should firearms cargopods, when shot up, explode with force equivalent to, let's say, a missile times (0% to 100%) ?


(I would expect a firearms cargopod filled with Quirium Bombs would, if shot at, come to bits and leave a rapidly dispersing cloud of fuel in the sky, rather than going off like a huge bomb.)

[Commander McLane]

What if the firearms cargopod just contains a collection of ancient  muskets?

[JensAyton]

That sounds dangerous. If a one tonne cargopod contains 500Kg of TNT, the save standoff distance on Earth is 125m when in a building or 550m when outdoors.

The primary destructive effect of conventional explosives is a shockwave, which travels through air (or other media). This is nullified in a vacuum, leaving only radiated heat and shrapnel.

[SandJ]

The primary destructive effect of conventional explosives is a shockwave, which travels through air (or other media). This is nullified in a vacuum, leaving only radiated heat and shrapnel.

Those safe distances are to cover the distance bits of stuff will travel - it is the shrapnel I was thinking off. A solid cargopod door coming at you propelled by an explosion is going to be akin to ramming another ship at full speed - it should at least knock out a shield.

Anyway, I am probably thinking too much. Having such specific logic as: only one cargo type, only sometimes, under certain circumstances, may cause a random amount of damage, depending on distance...

Not worth coding up. I retract my rambling.

[JensAyton]

A solid cargopod door coming at you propelled by an explosion is going to be akin to ramming another ship at full speed

I think not. Regardless of scale issues, I think it’s safe to say ships move very fast, and cargo pod doors are quite small. To get the same sort of momentum as a whole ship, you’d probably be looking at thousands of LM (whatever an LM is).

[Staer9]

A solid cargopod door coming at you propelled by an explosion is going to be akin to ramming another ship at full speed

I think not. Regardless of scale issues, I think it’s safe to say ships move very fast, and cargo pod doors are quite small. To get the same sort of momentum as a whole ship, you’d probably be looking at thousands of LM (whatever an LM is).

No... not really, in space those laws are seriously flawed, once when a spaceship went up (I cannot remember the name offhand) a fleck of paint peeled off and smashed a window (because it was traveling so fast) a cargo pod door would not only destroy the shield it would also destroy the ship... which makes you wonder about missile damage...

[Lone_Wolf]

it's the speed difference and vector that matters for such situations, not the absolute values.



Case A .
cargopod door speed = 50 LM
ship speed = 49.9 LM
Both are moving very fast in same direction.

Case B.
cargopod door speed = .6 LM
ship speed = .3 LM
both are moving in opposite directions towards each other.

which ship has better survival chance, A or B ?

[JensAyton]

No... not really, in space those laws are seriously flawed, once when a spaceship went up (I cannot remember the name offhand) a fleck of paint peeled off and smashed a window (because it was traveling so fast) a cargo pod door would not only destroy the shield it would also destroy the ship... which makes you wonder about missile damage...

This is basically irrelevant. You were comparing to the damage caused by two ships colliding. We can test this, and you’ll note that ships can collide at moderate speed without vaporising. To cause as much damage as another ship, a small object would need a very much higher closing speed. This tells us that Oolite ships are ridiculously robust, which is hardly surprising (and goes some way to answering that other thread about explosions).

[DaddyHoggy]

Isn't KE given by 1/2 m x v^2

Let's go for some completely arbitrary numbers, lets say a Cobra Mk3 weighs 1000 units (since we don't know other than Kgs and gs what any masses in Oolite are), let's say the cargopod door (I'm presuming you mean the door which protects the internal cargo bay from the elements) is 1% of the mass of the ship, 10 units.

Let us also normalise the maximum velocity of the Cobra Mk 3 to 1, since we don't know what an LM is, in relation to m/s and it makes the maths easier.

KE of a Cobra Mk3 = 0.5 x 1000 x 1^2 = 500 units.

Therefore for the cargo pod door to have the same KE as "another ship":

500 = 0.5 x 10 x v^2

1000 = 10v^2

100 = v^2

v=sqrt(100)

v = 10

So, very crudely, if the cargo bay door makes up 1% of the mass of the entire ship it would have to be travelling at least 10x as fast as a ship at max chat to have the equivalent KE...

A fleck of paint breaking some glass is probably not so unbelievable.

a 1g fleck of paint travelling at what say 1000m/s, compared to a 1000g head of a hammer travelling at only 5m/s swung by a human arm (and a 1kg hammer head is a heavy hammer, although 1g would be quite a lot of paint) = both will break the window.

[JensAyton]

I'm presuming you mean the door which protects the internal cargo bay from the elements

An actual piece of an exploded cargo pod is my understanding, so 1 % is kinda extremely high. :-) (Actually, it would be high for a cargo bay door too.)

[Eric Walch]

Case A .
cargopod door speed = 50 LM
ship speed = 49.9 LM
Both are moving very fast in same direction.

Case B.
cargopod door speed = .6 LM
ship speed = .3 LM
both are moving in opposite directions towards each other.

which ship has better survival chance, A or B ?

I assume case B. Ships are better protected against debris hitting them in front than from the back. So an object hitting it at a speed of 0.3 LM in the front will probably do less damage than the same object hitting it at 0.1 LM at its unprotected back.

(Or was it not it a trick question?)

[CommonSenseOTB]

What's missing from the equations is the effect of the shields. It is a science fiction invention and it is not known exactly how it works. What does matter is what makes sense to the average joe pilot. If I shoot an explosive cargopod I expect, based on how close it is, that the shield will take damage, but not much unless super close(short, point blank range). Would probably make sense that it would be under half the normal blast range of a missile. Maybe less than 100m distant from the exploding pod you would start to take damage. And colliding with it would be like getting hit by a low yield missile.

Here's a new tactic for you. Run from pirates. Dump a firearms cargopod and when the pirate goes to scoop it or comes near it you tag it with the rear laser. Would be cool if npc's did that too.

[Lone_Wolf]

Case A .
cargopod door speed = 50 LM
ship speed = 49.9 LM
Both are moving very fast in same direction.

Case B.
cargopod door speed = .6 LM
ship speed = .3 LM
both are moving in opposite directions towards each other.

which ship has better survival chance, A or B ?

I assume case B. Ships are better protected against debris hitting them in front than from the back. So an object hitting it at a speed of 0.3 LM in the front will probably do less damage than the same object hitting it at 0.1 LM at its unprotected back.

(Or was it not it a trick question?)

Nope, it's a real question with a valid answer.

I won't give you the answer, but unless front protection is atleast 81 times as good as back protection, your answer is wrong.

[Switeck]

We do not know what actual fraction of the speed of light in a vacuum these objects are traveling, which can thoroughly mess with their apparent mass. Nor do we know if ships travel partially or almost entirely by bending space around them so that from their point of view inside the bubble their speeds are only a tiny percent of the speed of light. Such might serve to mitigate impact speeds.

[DaddyHoggy]

I'm presuming you mean the door which protects the internal cargo bay from the elements

An actual piece of an exploded cargo pod is my understanding, so 1 % is kinda extremely high. (Actually, it would be high for a cargo bay door too.)

I thought 1% was very high too - but I chose it to show that even with such a large percentage - the velocity required by the piece of shrapnel was extreme to say the least.