Ballistics of a Fusion Gun?

[whartung]

I'm assuming that Fusion and Plasma guns simply "lob" blobs of energy and are therefore ballistic weapons, where as Lasers, PA's, and meson guns are line of site, light speed weapons.

The FGMP is known for its recoil, so that suggests a rather high velocity (as I don't imagine the charge actually having that much actual mass, but I don't know).

A larger gun sends more material, all of which is rather energetic, than a smaller, and that gives it better damage and penetration. Does it give the gun more range as well? Or does the velocity die off before the material consumes itself?

Given two different guns, shooting the same fusing material, if one fires it at a higher velocity, is there any reason it should not be viable at a longer range? How much does atmosphere affect the fusion bolt, either in drag or simply degrading its power?

If the bolt it particularly light, then drag would have a reasonable affect, you need mass to penetrate atmosphere at any reasonable velocity.

They don't rely on their velocity for penetration and damage, but I am curious what the ballistic properties of a fusion gun are. If anyone knows or has put any thought in to it.

 

[Foxroe]

Think of it as opening the valve on a firehose and spitting out a stream of the Sun...

There is a tremendous amount of energy in the superheated gas that comprises plasma. I imagine that the magnetically focused beam of gas coming from an energy weapon has a great deal of velocity, and therefore produces some kick in the opposite direction. The beam itself would require continuous magnetic compression from gun to target to prevent the heated gas from dissipating over distance. A "fusion" beam is pretty much the same thing, only that the gas is hot enough to start fusion reactions, therefore producing more energy than is required to generate the beam.

At least that's how I picture it, but seeing as it's a fictional device, it would be entirely up to you as to how it operates in YTU.

-Fox

 

[Major B]

In MT, fusion and plasma guns have an attenuation factor of 5 meaning their penetration diminishes over distance, but not by a lot. A factor of 5 suggests that they are high velocity projectiles - I think the attenuation would be lower otherwise.

To me that means they are ballistic, but I think the ballistic path would be pretty flat - more like the arc of a rifle bullet rather than that of a mortar round.

 

[Andrew Boulton]

Velocity is 8000m/s, according to FF&S.

 

[far-trader]

On the face of it 8000m/s sounds positively insanely high. Even 8000ft/s would be very high velocity. Not disputing the number, just the reasoning behind it. I suspect a decimal error, 800m/s would be "reasonable" for a rifle muzzle velocity.

But FF&S is very poor at modeling extremes of conventional firearms so I wouldn't be surprised to find the modeling of fictional weapons to not compare well.

 

[far-trader]

My take on the PGMP-12 for what it's worth (similar in concept to my take on the FGMP series)

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=5007

(I really need to pull my stuff together and resurrect/continue that thread and some other ideas... )

 

[Merxiless]

I don't think 8k m/s is too fast.

It's plasma.

Maybe we can look up the speed of a solar flare...

 

[far-trader]

Fastest CME recorded was about 2,700 km/s...

But that's in a vacuum, with the power of the sun pushing it, I don't think even TL15 can pack that kind of punch in a backpack hand held rifle and still leave the trooper firing it standing after

Even the kick from firing a small ball of plasma at 8 km/s is going to (at a guess) knock the trooper firing the weapon flat on their can even if they are properly braced and wearing strength enhancing BD.

 

[Spinward Scout]

8000 meters per second is only about 5 miles per second or about 300 miles per hour. I believe Mach 1 is 720 miles per hour.

 

[whartung]

8000 meters per second is only about 5 miles per second or about 300 miles per hour. I believe Mach 1 is 720 miles per hour.

Umm..no...Mach 1 is about 1000-1100 fps.

How do I know this?

A lot of air rifle makers strive to keep their rifles down below (but just below) that mark, because when they cross Mach 1, the rifle suddenly becomes much louder due to the crack of the projectile breaking the sound barrier.

And silence is a quality that many air rifle shooters look for.

There, more trivia to bedazzle your friends and coworkers with.

 

[Merxiless]

5 miles per second is

300 miles a minute

18,000 MPH

 

[aramis]

5 miles per second is

300 miles a minute

18,000 MPH

Bloody fast for a "projectile" and somewhat slow for a particle beam.

 

[Icosahedron]

I think the general idea of plasma/fusion weapons is that they should be much faster than targets, but much slower than sensors, having an effectively flat trajectory over their feasible range, with precise details left to the GM.

IMTU, fusion gun power packs are under-unity fusion plants that fire (rather than contain) pulses of fusing plasma. I figure they stop fusing as soon as they leave the weapon, but nevertheless have a higher energy content than pulses of non-fusing plasma.

 

[Gadrin]

I believe the cover of GURPS Traveller's Ground Forces illustrates what
the fusion gun of a grav tank would look like. The guy on top is using his
personal weapon too...

http://visionforgestudios.com/jesse/traveller/ground_forces_test_shots.htm

 

[Spinward Scout]

5 miles per second is

300 miles a minute

18,000 MPH

D'oh! Did my math wrong. Sorry!

 

[Foxroe]

IMTU, fusion gun power packs are under-unity fusion plants that fire (rather than contain) pulses of fusing plasma. I figure they stop fusing as soon as they leave the weapon, but nevertheless have a higher energy content than pulses of non-fusing plasma.

I always considered that the FGMP sustained the fusion reaction until firing, the energy state of the plasma being at unity in the weapon, but then losing energy as the beam left the weapon. But I guess your explanaton works just as well, if not better: There would be less energy required to heat the plasma to a sub-unity fusion state than to unity itself.

-Fox

 

[Blue Ghost]

I'm assuming that Fusion and Plasma guns simply "lob" blobs of energy and are therefore ballistic weapons, where as Lasers, PA's, and meson guns are line of site, light speed weapons.

The FGMP is known for its recoil, so that suggests a rather high velocity (as I don't imagine the charge actually having that much actual mass, but I don't know).

A larger gun sends more material, all of which is rather energetic, than a smaller, and that gives it better damage and penetration. Does it give the gun more range as well? Or does the velocity die off before the material consumes itself?

Given two different guns, shooting the same fusing material, if one fires it at a higher velocity, is there any reason it should not be viable at a longer range? How much does atmosphere affect the fusion bolt, either in drag or simply degrading its power?

If the bolt it particularly light, then drag would have a reasonable affect, you need mass to penetrate atmosphere at any reasonable velocity.

They don't rely on their velocity for penetration and damage, but I am curious what the ballistic properties of a fusion gun are. If anyone knows or has put any thought in to it.

The recoil is from the ignition of the beam, not from releasing it from the barrel.