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Vote Your Canon #5: Fusion Rockets / HEPlaR (consensus: Yes)

Are fusion rockets and/or HEPlaR canon?

  • Total voters
    27
  • Poll closed .
robject

robject

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1977 and HG1 used terms like mass when referring to starships, and suggested that ships could use their fusion rocket drives as weapons.

For the sake of hasty generalization I will refer to this as HEPlaR.
 
Does Marc still talk to Frank? Has he read any of Frank's interviews about TNE?

LBB5 79 m-drives are fusion rockets
TNE m-drives have always been fusion rockets/HEPlaR as a deliberate change to move away from the electrically powered thruster plates of MT and back to the original intent of a reaction drive as m-drive (according to Frank Chadwick).

But as Another Dilbert has pointed out there is no putting the grav based reactionless thruster back in its box (MgT, T5)
 
I have used them as such, even to go as far as posting tables for conversion from either LBB2 or CE. Just thought about writing up a more comprehensive version of LBB2 with them for play.
 
AnotherDilbert said:
Yes, of course, they are even in T5.

But why would anyone use them when "reactionless" M-drives are available?
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Sure. But as AD points out, why bother?

As a counterpoint, much of Traveller-related art (and a vast amount of SF -- particularly from the era that inspired Marc to write Traveller) depicts spacecraft with what appear to be reaction engines. So, in practice you end up with propulsion systems that look and feel like reaction engines, but which are played as reactionless drives for simplicity.
 
I rather like the idea that HEPlaR or Fusion Rocket is standard from about TL9/10 to Tl11/12, and then the M-Drive replaces it for higher TL. That nicely showcases the increase in technical sophistication and capability with increasing TL - especially in settings like Milieu:0 where Sylea can show the flag with its sophisticated new TL12 stuff compared to the colonials and pocket empires.

Just like when repeating rifles and brass casings became available for firearms, people got rid if their black-powder percussion revolvers and muzzle-loaders almost overnight.
 
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HePLAR is simply too obvious (and useful) of a technology to discard completely, even if it isn't that necessary for pre/post-jump maneuvering.

I figure that even with Thruster Plates, HePLAR is still used as a backup option for truly deep space maneuvering beyond 1000 diameters to the nearest gravity well.

Spoiler alert ... HePLAR is going to need to come back into use once Hop Drive technology is discovered.
Jump points are (beyond) 100 diameters distant.
Hop points are (beyond) 1000 diameters distant ... and M-Drive Thruster Plates basically reach their useful limit at (wait for it...) 1000 diameters.
So having a reaction drive that works beyond 1000 diameters, when the reactionless drive stops working at 1000 diameters, is going to be A Thing™.
 
mike wightman said:
Does Marc still talk to Frank? Has he read any of Frank's interviews about TNE?

LBB5 79 m-drives are fusion rockets
TNE m-drives have always been fusion rockets/HEPlaR as a deliberate change to move away from the electrically powered thruster plates of MT and back to the original intent of a reaction drive as m-drive (according to Frank Chadwick).

But as Another Dilbert has pointed out there is no putting the grav based reactionless thruster back in its box (MgT, T5)
Click to expand...

Book 2 '77 p22:
3. Thrust: Ships maneuver using reaction drives, referred to as M-Drive or maneuver drive.
Click to expand...

But, it was just pointed out to me that, regardless of what the "original intent" was, said intent never explained itself sufficiently in CT'77. In effect, the maneuver drive has always been the maneuver drive, no matter what you called it... a "reaction drive" had no consequences.

*with the exception of using it as a weapon in HG1.


I mean, a few tons of fuel were good for a month of maneuver operations (on starships). That's certainly not HEPlaR, and the reaction mass is so small that there's nothing really going on that's worth calling it "reaction" for.
 
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robject said:
*with the exception of using it as a weapon in HG1.
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Which is why I think it looks like a fusion rocket in LBB2 '77. Well, that and the maneuver drive being something with a 1Td hole in the middle (it's sized at 2%Td MINUS 1Td) that's bolted onto the fusion reactor -- a fusion reactor that in '77 isn't used for anything else.

Again, though, until HG '77 it's unspecified, and in general the consequences of the exhaust plume get handwaved away so it may as well be a magic grav drive as far as the game (but not its artwork) is concerned.
 
Anyway, proves my point that 'canon' based on CT is not necessarily a reliable standard. You still have to pick and choose.
 
The fuel on a ship is not good for 4 weeks maneuvering, at the fuel use rate of LBB2 a ship has 48 hours of continuous thrust available not 4 weeks. Enough that an few hours of combat doesn't need you to track fuel. But if you are going to be moving around a system for a while fuel use becomes an important factor, hence the more detailed rules of Beltstrike.

The design intent behind TNE was to make fuel a resource you had to manage rather than have a ship that is just point and go.

Oh, and the power plant is used for something other than powering the m-drive - page 11 it provides internal power for the ship.
 
mike wightman said:
The fuel on a ship is not good for 4 weeks maneuvering, at the fuel use rate of LBB2 a ship has 48 hours of continuous thrust available not 4 weeks. Enough that an few hours of combat doesn't need you to track fuel. But if you are going to be moving around a system for a while fuel use becomes an important factor, hence the more detailed rules of Beltstrike.

The design intent behind TNE was to make fuel a resource you had to manage rather than have a ship that is just point and go,
Click to expand...
It was 48 hours in '77. In '81, that changed to "four weeks" of undefined use.

Players and refs who hadn't seen the '77 rules would have no idea that it was supposed to only cover 48 hours of full-power maneuvering over the course of those four weeks, though it's quite reasonable to read that intent into the revised rules.
 
I use them in my games (mostly MT), but as described in "One Small Step" rules (HT), as an alternative.
 
mike wightman said:
LBB2 a ship has 48 hours of continuous thrust available
Click to expand...
Grav_Moped said:
It was 48 hours in '77.
Players and refs who hadn't seen the '77 rules would have no idea that it was supposed to only cover 48 hours of full-power maneuvering
Click to expand...

Interplanetary Travel Distance by Time and Acceleration
1G2G3G4G5G6G
48 hours (2.0d)74,649,600 km (0.499 AU)149,299,200 km (0.998 AU)223,948,800 km (1.496 AU)298,598,400 km (1.996 AU)373,248,000 km (2.495 AU)447,897,600 km (2.993 AU)

You can't get anywhere useful in 48 hours of power maneuvering using 1-2G drives a lot of the time.
Simple fact of the matter is that 48 hours of powered maneuvering just isn't enough for useful interplanetary adventuring.
 
mike wightman said:
Accelerate - coast - decelerate. You can get anywhere in the solar system with a 1g drive, it just takes a bit longer.
Click to expand...
It doesn't quite feel like post-HG '79-Traveller where everything goes brachiostochrone , but it's a perfectly valid way to get around!
 
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