Hydrogen needs for high energy weapons

[McPerth]

Maybe this is quite a dumb question, so I apologize beforehand to anyone so thinking, but, how much hydrogen does a plasma or fusion bolt need?

Let me explain myself:

High energy weapons are told (CT:Bk4, page 37 and MT:IE page 72) to heat hydrogen to the point of producing plasma (or to the fusion point) and launch it, as bolts 2 cm in diameter, at high speeds to produce both kinetic and thermal damage, so hinting that they must have a minimum mass (otherwise no kinetic damage would be produced).

Nevertheless, no hydrogen is loaded in the weapons, and they work just on energy (as do vehicular or starship high energy weapons). I understand the hydrogen needed may be irrelevant for vehicles and spacecrafts, who carry it in their fuel tanks, but for portable weapons that have no limit to ammo due to being energy fed by micro fusion plants, there shuld be a limit also due to hydrogen needed to create the fusion bolt, as would any such vehicle or craft not powered by hydrogen (e.g. solar powered).

 

[Vladika]

Maybe this is quite a dumb question, ...

Not dumb at all! I'm surprised that it hasn't come up before.

...but for portable weapons that have no limit to ammo due to being energy fed by micro fusion plants, there shuld be a limit also due to hydrogen needed to create the fusion bolt, as would any such vehicle or craft not powered by hydrogen (e.g. solar powered).

We might need some RetCon Handwavium and say:

A) It doesn't take much Hydrogen

B) The required amount is in the carried power pack and comes through a separate "hose" along with the massive amount of energy also magically provided.

I've always liked Traveller overall penchant for old fashioned slug throwing weapons myself.

 

[samuelvss]

I thought that the kinetic energy was from the explosively vaporized in the target. I have been much more wrong about far more important subjects, however.

 

[BytePro]

Classic Reprints CT:Bk4, page 37 -

'Plasma Gun ... heats hydrogen fuel to a plasma state ... released ... along the barrel ... high initial velocity plasma jet is 2 cm in diameter but begins to dissipate immediately. Each power pack has sufficient energy to discharge 40 plasma bolts before recharging.'

Seems to answer this question pretty clearly. Other than the term 'sufficient energy' might be better stated 'sufficient fuel' what is the issue?

[The KE comes from -> very small mass x very great velocity.]

 

[Enoki]

With current technology it only takes a couple of kilowatts at high frequency (450 Khz or 2 - 4Mhz) at 480 volts to produce a pretty big amount of hydrogen plasma. Of course that is for a plasma torch so it doesn't go anywhere like a fusion or plasma weapon's does.

I'd surmise it should be possible to have a fuel cell generate the electrical power using some of the same hydrogen the weapon fires to power the plasma or fusion part. Firing it... I'd say that is PFM right now.

 

[Carlobrand]

Maybe this is quite a dumb question, so I apologize beforehand to anyone so thinking, but, how much hydrogen does a plasma or fusion bolt need?

Let me explain myself:

High energy weapons are told (CT:Bk4, page 37 and MT:IE page 72) heat hydrogen to the point of producing plasma (or to the fusion point) and lauch it, as bolts 2 cm in diameter, at high speeds to produce both kinetic and thermal damage, so hinting that they must have a minimum mass (otherwise no kinetic damage would be produced).

Nevertheless, no hydrogen is loaded in the weapons, and they work just on energy (as do vehicular or starship high energy weapons). I understand the hydrogen needed may be irrelevant for vehicles and spacecrafts, who carry it in their fuel tanks, but for portable weapons that have no limit to ammo due to being energy fed by micro fusion plants, there shuld be a limit also due to hydrogen needed to create the fusion bolt, as would any such vehicle or craft not powered by hydrogen (e.g. solar powered).

Aside from the PGMP-12, the energy weapons are hooked up to backpack portable fusion plants for power; these could also provide the hydrogen. Possibly the battery pack for the PGMP-12 also contains a hydrogen reservoir.

I recall a rather extended discussion some time back where we had a lot of trouble making the PGMP/FGMP series work. The PGMP-12 in particular was handicapped by the fact that it couldn't put out more power than, say, an elephant rifle without ending up hurting the shooter. Because the Book-4 entry described it as projecting a 2 cm diameter jet, the math ended up making it look like a very hot, very fast but rather low-density jet of plasma, like a rocket jet. It ended up looking more like a very high temperature flamethrower than a penetrating weapon. Making it work as a penetrator requires narrowing the jet down to a needle-like affair.

 

[Kaeto]

Well if you were to use the description of the Hellbore in the novel Bolo Rising. The ammunition for a FGMP or a PGMP could be a sliver of hydrogen slush of a few grams of mass, coated in super dense that has been compressed to a metallic state. It is held suspended in a magnetic field until the moment of firing, then the plama is launched down the barrel of the weapon a split-second after a laser fires to clear the bore and the firing path of air.

Of course Hellbores are in the 20 cm or better range an they launch the plasma bolt at .6 lightspeed.

 

[McPerth]

Classic Reprints CT:Bk4, page 37 -

'Plasma Gun ... heats hydrogen fuel to a plasma state ... released ... along the barrel ... high initial velocity plasma jet is 2 cm in diameter but begins to dissipate immediately. Each power pack has sufficient energy to discharge 40 plasma bolts before recharging.'

Seems to answer this question pretty clearly. Other than the term 'sufficient energy' might be better stated 'sufficient fuel' what is the issue?

[The KE comes from -> very small mass x very great velocity.]

Same quote than you, just some lines below:

Recharging requires four hour's connected to a high energy source (such as a ship's power plant).

As the ship's power plant is used just as example, I guess other power sources would also work (such as the planet's power gird, akin of RL electric cars).

This would recharge the power of the weapon, but the issue is: where does the hydrogen to be heated and released come from?

Same happens if you (using as example MT rules, as I don't know striker's) build a bunker (in fact an inmobile vehicle) armed with a Plasma/fusion gun (anything from a PA-10 to a RFY-15, all in MT:RM page 78). You can fed the power for them by connecting it to the power gird, or by using solar array/batteries, but, again, what about the hydrogen needed to be heated and fired? (and this time I guess you'll need a little more per shot than for man portable weapons, and the RP/RF weapons have quite high ROF).

And last example (at least in this post) would be a solar powered defense satellite armed with a FG turret/bay. The power needs are clear and accounted for, but again, what does it heat and fire if it has no hydrogen on it?

 

[Fritz_Brown]

I was under the impression the plasma was generated by "incomplete" fusion?

 

[McPerth]

I was under the impression the plasma was generated by "incomplete" fusion?

As I understand it, it stops heating the hydrogen before it reaches the fusion point.

My guess is that it's done because if it reaches fusion point it could not be controlled, and so it's released before it. As TLs advance, it can be controlled and so it's heated to the fusion point before releasing it.

 

[Dragoner]

Because the Book-4 entry described it as projecting a 2 cm diameter jet, the math ended up making it look like a very hot, very fast but rather low-density jet of plasma, like a rocket jet. It ended up looking more like a very high temperature flamethrower than a penetrating weapon. Making it work as a penetrator requires narrowing the jet down to a needle-like affair.

Usually after doing the KE = 1/2mv^2, the kg/ms is converted to joules; big penetrators effectively burn through armor, though it is far more complex than that.

 

[BytePro]

...
Nevertheless, no hydrogen is loaded in the weapons, and they work just on energy (as do vehicular or starship high energy weapons).

That is only valid for the PGMP-12, keep reading the other weapons listed on pg 38 -
'refueling: CR 20 ... refueling: CR 50 ... refueling: CR 70'

The description and all the other weapons specify hydrogen fuel.

The PGMP-12 is the only one that doesn't explicitly state the cost for fuel. The 'commercial cost to recharge: CR 50' can either include 'recharging fuel' or one could add it separately (Cr: 20 or less) - as obviously it was missed or not clarified. <Shrug> No shocker with LBB4...

(P.S. - have you checked the errata?)

 

[BlackBat242]

As the ship's power plant is used just as example, I guess other power sources would also work (such as the planet's power gird, akin of RL electric cars).

This would recharge the power of the weapon, but the issue is: where does the hydrogen to be heated and released come from?

The same place as the hydrogen the power plant is running on does... the ship's power-plant fuel tank.

The connection would include both a high-power electrical contact and a quick-disconnect hose for hydrogen replenishment.

 

[Fritz_Brown]

and a quack-disconnect hose

So.... this is what you would repair with duck tape?

 

[BlackBat242]

No, no need for that here... just better proof-reading. :rofl:

 

[McPerth]

That is only valid for the PGMP-12, keep reading the other weapons listed on pg 38 -
'refueling: CR 20 ... refueling: CR 50 ... refueling: CR 70'

The description and all the other weapons specify hydrogen fuel.

The PGMP-12 is the only one that doesn't explicitly state the cost for fuel. The 'commercial cost to recharge: CR 50' can either include 'recharging fuel' or one could add it separately (Cr: 20 or less) - as obviously it was missed or not clarified. <Shrug> No shocker with LBB4...

And that is why I didn't talk about TL13+ PGMP/FGMP, though, being fed by a micro fusion plant, the hydrogen may be for either, and see that they have no limits on shoots, but on time, regardless you fire it only once or every round for 24 hours, so hinting that no hydrogen is spent by firing, just by fueling the fusion plant.

(P.S. - have you checked the errata?)

Nothing there about that issue (neither in CT nor in MT errata)

The same place as the hydrogen the power plant is running on does... the ship's power-plant fuel tank.

The connection would include both a high-power electrical contact and a quick-disconnect hose for hydrogen replenishment.

That would be true if you use a ship PP, and even there I guess there are not many connections to take hydrogen from the fuel tanks on it, so it would need some modifications in the ship itself to have this hydrogen line instead of a simple power take, but if you use a solar array/batteries (this is quite posible, in MT at least) or just connection to the planetary power gird (as in the examples I gave)?

 

[DangerousThing]

That would be true if you use a ship PP, and even there I guess there are not many connections to take hydrogen from the fuel tanks on it, so it would need some modifications in the ship itself to have this hydrogen line instead of a simple power take, but if you use a solar array/batteries (this is quite posible, in MT at least) or just connection to the planetary power gird (as in the examples I gave)?

I suspect that this is one of those things that are simplified because it is a game.

When I used a version of these in a game, I used a smaller version that used lasers to turn a small packet of lithium into plasma. I didn't have a fusion version in that game. And in my current game they don't exist, at least for the characters.

 

[McPerth]

I suspect that this is one of those things that are simplified because it is a game.

Sure, but this would allow you to have a PGMP 12 armed unit out of supply just recharging their weapons on power (again, imagine a solar array), and so keeping ammo supplied while out of supply. Curiously enough this makes the PGMP-12 less ammo dependent than the latter versions, that have to refuel (and maintain) their micro-fusion plants...

While I undertand this to be posible if armed with laser weapons, as they just need the power, but high energy weapons shoot hydrogen, and so must need it.

And this could also explain why Zhodani Consular Guard units, being TL 14 units, are depicted as laser armed, instead of using the more powerful high energy weapons, as they are thought to fight behind enemy lines, so many times out of supply.

 

[CosmicGamer]

Sure, but this would allow you to have a PGMP 12 armed unit out of supply just recharging their weapons on power (again, imagine a solar array), and so keeping ammo supplied while out of supply.

Perhaps it assumes that water is available for multiple reasons. Drinking? How long can troops go without any water at all?

Maybe they didn't want to go into the gross details of troops opening the port for the weapons built in filtering and H reclamation system and pissing into it. :rofl:

 

[BytePro]

And that is why I didn't talk about TL13+ PGMP/FGMP, though, being fed by a micro fusion plant, the hydrogem may be for either, and see that they have no limits on shoots, but on time, regardless you fire it only once or every round for 24 hours, so hinting that no hydrogen is spent by firing, just by fueling the fusion plant.

Sorry, you might have meant to talk only about PGMP12, but that's not clear in what you posted.

The wording for the higher TL guns is, of course, very poor - 'The power pack is a small fusion reactor with effectively unlimited fuel for combat purposes (but requires periodic refueling and routine maintenance every 24-36 hours, depending on amount of use).' But, this is consistent with the writing and mechanics in the rest of the book. I.e. - effectively unlimited, but with the following limits...

Obviously, all of this poorly written fluff is about coming up with in-game rationalizations for a bunch of meta-game rules designed to put limits on these munchkin style weapons. It is done just as poorly as the 2d6 curve breaking mechanics in this book whose complexity broke with the flavor of the original 3 books. IMO, LBB4 demonstrated a fundamental weakness with basic math and fully thought out logic. Its a mish-mash of high/low level details that clashes with the original works. Its descriptions contain a lot of unneeded information (prone to contradiction or outdating) such as munition velocities. IMO, this is because it wasn't designed by Marc, but Frank Chadwick.

In this particular instance, aside from not clearly qualifying fuel and power usage - the 40 bolt limit is laughable given the mechanic supported damage dice and the fact this covers 80 combat rounds given the other limit placed on this weapon. For the intended meta-game effect - and maintaining the balance of LBB1-3, while differentiating the weapons - it should have been more like 4 bolts before refueling and recharging. Recharging of the PGMP12 should have stated the inclusion of fuel - though that is the least of the needed fixes... <shrug>

It may be apparent - but I was not a fan of LBB4. I was 12, but my math and analytical skills already exceeded what this book had to offer. One read of the chargen and I laughed and never considered it again. Aside from the idea of mercenary tickets, PGMP/FGMP were about the only thing I actually adopted from this book, but with significant fixes. Ironically, LBB4 was the first book I actually could find to buy back in the day!