HEPlaR drives

[TJP]

I'm not quite sure I understand how HEPlaR drives are supposed to work. So far I've come up with two theories:

1. HEPlaR drive is a fusion reactor that has been designed to leak in a controlled fashion. This leaking fusion plasma is the reaction mass that provides thrust (that can be accelerated further magnetically or gravitically to provide higner exhaust velocity). It uses either deuterium or "simple" hydrogen (can't remember what it was called...protium?) as fuel/remass. In other words, more or less a glorified fusion rocket.

2. HEPlaR has a fusion reactor to heat reaction mass (that can be almost anything, water's good) and then it is accelerated and expelled to provide thrust. This differs from version 1 above, in that the remass does not enter into the reactor but is only heated by it.

Now, I don't think either of the above explanations are correct. For starters HEPlaR drives didn't have an internal fusion reactor, but required power from an external source. They also seemed to consist only of a "thruster unit" that was recombining plasma (or something). Et cetera.

Neither the TNE rule book nor T4 FFS really explain the HEPlaR drive, even though both mention them. I recall that T4 FFS gave HEPlaR an incredible performance (the exhaust velocity was tremendous). However, that's not the issue here, I'd just like to know if any of you out there in cyberland know what HEPlaR is about.

PS. I suspect HEPlaR was just another example of technobabble, even though an elegant one (trying to pose as hard SF). I'm not scientifically educated enough to know the difference, though. I can only spot (as technobabble) stuff like delta-wave boron inducers and subspace radiation inverter coils. Trek anyone?

 

[DaveShayne]

From FFS1 (the original for TNE) page 70:

"HEPLaR: The other thrust agency, high efficiency plasma recombustion (HEPLaR), becomes available at tech level 10. It my (sic.) be added to any power plant by adding a heat exchanger recombustion chamber to the plant. Hydrogen is injected into the recombustion chamber and the power generated by the engine heats the hydrogen to a plasma state. The plasma is then released as a high velocity stream of reaction mass, providing thrust."

Does this answer your question?



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I am increasingly of the opinion that RPGs are by the nature of their creation subjective phenomenon. due to the interaction between game designers, game masters, and game players all definitions, rules, settings, and adventures are mutable in acordance with the uncertainty principle as expounded by Heisenburg. This is of course merely my point of view.

David Shayne

 

[Christopher Jennings]

So in other words its one step away from the old Fusion Torch drives. OK for vacume, but I have say that IMTU all developed worlds with any kind of ecology ban the operation of such drives inside the atmosphere. That would imply that ships with those kind of drives either stick to vac worlds or use the orbital facilties. If they came down under power they probably would face prosicution and/or hefty fines, and they certainly wouldn't be allowed to take off under their own power. So profits on that trip would probably be nill.

 

[DaveShayne]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Christopher Jennings:
So in other words its one step away from the old Fusion Torch drives. OK for vacume, but I have say that IMTU all developed worlds with any kind of ecology ban the operation of such drives inside the atmosphere. <HR></BLOCKQUOTE>

Two things to bear in mind. First, the hydrogen plasma of HEPLaR doesn't fuse so no radiation. Second, TNE contra-grav is described as able to lift a ship to orbit (something about boyancy) so you wouldn't have to engage the HEPLaR (or Fusion Rocket also described in FFS1) untill out of the planets atmosphere. Third (Cue Python joke), the big problem with HEPLaR is the game problem of having to worry about all of that fuel consumption. I don't wanna have to keep an eye on the fuel gage when I play.



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I am increasingly of the opinion that RPGs are by the nature of their creation subjective phenomenon. due to the interaction between game designers, game masters, and game players all definitions, rules, settings, and adventures are mutable in acordance with the uncertainty principle as expounded by Heisenburg. This is of course merely my point of view.

David Shayne

 

[TJP]

Yes, that answers it, thank you. Was the original FFS any better than the T4 FFS (which, IMHO, is a disaster)?

I'm not overly fond of watching the fuel gauge either. I'm just putting together a new campaign which tries to be more of hard SF than space opera. Therefore I've been looking for a good reaction drive for starships as I try to avoid reactionless drives and gravitics altogether. However, those reaction drives do give me a mathematical headache.

Speaking of mathematics, are there any mathematically gifted people out there who could tell me how to calculate the interior volume of a torus (donut-shape) and its surface area? Without gravitics I need rotating habitat rings for space stations, you see.

(Yes, I was the guy in math classes who sat in the back row drawing pictures to the math book, I confess, I should've listened...)

 

[bgueldner]

I'm not a mathematical genius, but I was intrigued by your question regarding the surface area (S) and interior volume (V) of a ring torus and found this:
http://mathworld.pdox.net/math/t/t200.htm

I think this should answer your questions.

- Brian


[This message has been edited by bgueldner (edited 02 September 2001).]

 

[DaveShayne]

<BLOCKQUOTE>quote:</font><HR>Originally posted by TJP:
Yes, that answers it, thank you. Was the original FFS any better than the T4 FFS (which, IMHO, is a disaster)?<HR></BLOCKQUOTE>

I supose it depends on what you like. The original book has a lot more alternate technologies than FFS2 but it also is much easier to read and has far less errata. So if you are looking for a usable game supplement then you want FFS1. If on the other hand you want to curse loudly about what total and complete incompetent weenies Imperium Games were then you need FFS2.

OK that's a little harsh. FFS2 has some cool stuff in it but it really needed one more trip through playtest and two more trips past the editor. Personally I'm glad I have both but I wouldn't go back into a burning building for FFS2.



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I am increasingly of the opinion that RPGs are by the nature of their creation subjective phenomenon. due to the interaction between game designers, game masters, and game players all definitions, rules, settings, and adventures are mutable in acordance with the uncertainty principle as expounded by Heisenburg. This is of course merely my point of view.

David Shayne

 

[TJP]

Thanks again! That site was very helpful. Found lots of useful formulas to help me in my design efforts. My old math teacher would not belive that I'm actually voluntarily seeking geometry formulas. My level of gearheadedness is starting to reach critical levels...

Now to just find that FFS1 somewhere.

 

[Spinward Scout]

Hopefully Marc will take the good points from each book if he ever does a FFS3 for T5 - or if there's something in mind for T20. I like all the alternate technologies - makes the aliens seem more individual.

later,

Scout

 

[rtartis]

So Can a HePlar drive be added to ANY engine (even my old pickup trucks IC engine?)

 

[GypsyComet]

Sort of. The equivalent for an IC engine would be an unmuffled sparker in the exhaust pipe, on the theory that the flames shooting out the pipe will provide more acceleration...

 

[rtartis]

True, But where in the FF&S book does it say hePLar must be attached to a Fusion Engine.

Also How can there be TL 12 HePlar Missiles since the Minimum Volume for a Fusion plant exceeds the 7 kton size of the missile?