The Bridge, Ship Size, and Hull Size
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mike wightman
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I agree with Another Dilbert, here is what it says in HG80 page 22
And on page 27
The only point of discussion is if you can mix them. I don't see why you wouldn't use Book 2 m-drives on every ship up to 2000t.
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Liked for this.
And on page 27
How much fuel should a LBB2 maneuver drive use?
Edit to add: I'm referring back to LBB2'77 where the power plant existed solely to support the maneuver drive (give or take Double-Fire capability). The maneuver drive handwave changed in '81 (from rocket exhaust to grav drive) but the characteristics of it did not.
Edit2: Post #104 beat my edit.
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Varies by which LBB2... 77 is some fraction on 10Pn; 81 is none...
Which wasn't quite my question -- or rather, kind of was, after my edit-while-you-were-posting. '77 rules had the fuel used by the power plant and maneuver drive in tandem since there was an implied integration of the two components.
Oh, wait. This gets weird.
HG'80 changed the HG M-Drive to a grav drive before LBB2'81 came out, so for a while there the controlling system for LBB2 was still the '77 rules*.
Rules that included fusion-rocket maneuver drives.
Which is to say, LBB2 maneuver drives (rockets using the power plant exhaust) would have been incompatible with HG powerplants (that only supply electric power to a grav drive along with everything else) when HG'80 came out.
This didn't change until LBB2'81.
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*plus the optional accessory jump governor component.
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True. On the other hand, they did fix the LBB2 jump governor issue in HG1 (I think -- or was it in an issue of JTAS?)
AnotherDilbert
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As Mike showed, it's explicitly allowed.
Allowed, not mandatory.
I can't pretend that S9 ships are very efficient or fit for purpose.
Wouldn't have worked (due to technobabble incompatibility) when they wrote HG'80, and the writers would have known that. It might have after LBB2'81, to the extent that the writers thought about it.
AnotherDilbert
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As much as in LBB2, which is negligible, even LBB2'77.
The "reaction drive" in LBB2'77 uses power from the power plant, but no propellant.
Only HG'79 talks about "fusion drive", not specifically fusion rocket. Still doesn't use any measurable propellant.
The "reaction drive" in LBB2'77 uses all of the fuel the power plant uses, because the power plant doesn't appear to supply significant power to any other ship system (yet). And it does so at rates explicitly defined as analogous to (but not identical to) LBB2'77 small craft fuel consumption.
AnotherDilbert
SOC-14 1K
HG'80 didn't require any specific version of LBB2. HG'80, p17 refers to a specific page in LBB2'77.
Fuel worked the same in all versions of LBB2 and LBB5: No fuel consumed by the M-drive.
AnotherDilbert
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The power plant consumes fuel to produce power for all ship's systems:
That fuel is enough to accelerate for weeks on end, see p1.
Ship's fuel consumption is no-where near small craft consumption.
Power is consumed by other systems (of course):
LBB5¨79 expanded to say:
You may want to imagine a big rocket on Traveller ships, but that is not what Traveller actually says, even in '77.
No. It's "at least 288 turns" worth, and the entire allocation is used every trip (typically 9 days, though there's no reason a trip couldn't be longer -- especially when not accelerating constantly).
If it's just 288 turns, it's at slightly more than triple small craft rates. It's clearly lower than that, but not likely less than the small craft rates.
Condottiere
SOC-14 5K
One assumes nuclear reactor and jump drive engineering requires a rather qualified and experienced crewman.
On the other hand, maybe all you need is to watch a couple of dials, and adjust some levers, in the fifty sixth century, for twenty tonnes worth.
On the other hand, maybe all you need is to watch a couple of dials, and adjust some levers, in the fifty sixth century, for twenty tonnes worth.
Which require so little power that the '77 version of the XBoat didn't actually require a power plant.
AnotherDilbert
SOC-14 1K
The combat chapter says:
The travel time chart says:
Constant acceleration for 9.6 days is a "typical travel time".
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(... and setting aside the preposterous '77 fuel burn rates that ignored the mass of the craft.)
1 billion miles is not typical. 100D for a Size 8 world is 16.2 million miles (21.6 million km). Each end of a jump between two such worlds requires about one day at 1G for the transit to Jump Limit, assuming a jump at zero velocity wrt the origin world and arrival with zero velocity wrt the destination world.
In other words, that's the "at least 288 turns" (2 days) of fuel right there. Enough for a typical trip, but implying enough of a margin to cover trips with refueling at gas giants (and their much greater 100D limits) at each end -- basically, "enough that you don't have to worry about it, just call it all burned-off each trip and it'll balance out over time".
In context, "typical travel time" as used in the infobox means the typical time needed to travel that distance, not that it is a typical distance traveled.
(It's interesting that they used 1G for that infobox, rather than the table provided in the '80 version that covered the range of 1-6Gs.)
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AnotherDilbert
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It's a game, it has to be simplified. The rocket equation isn't simple enough...
LBB2'77, p1 disagrees:
109 miles is the rough region of a trip to a gas giant for a quick refuel.
