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MGT Fuel

Jame

SOC-14 5K
Now let's see if we can do this calmly.

I also dislike MGT's rule about fuel lasting only 2 weeks, but I did write up a retcoon about it - fuel efficiency would go up with TL. My other way around it would be to say that it's two weeks manuever fuel, and calculate it by the M-Drive type.
 
Now let's see if we can do this calmly.

I also dislike MGT's rule about fuel lasting only 2 weeks, but I did write up a retcoon about it - fuel efficiency would go up with TL. My other way around it would be to say that it's two weeks manuever fuel, and calculate it by the M-Drive type.

I'm not sure this is really a valid way to do it - not because of any R00LZ, but sheer logic: you're not necessarily continuously "maneuvering" (running the M-Drive) - you could simply be accelerating to a 'comfortable' speed, and then 'going ballistic' for the middle part of your trip, and then accelerating again to match velocity with your destination. Admittedly, this isn't actually a LIKELY scenario; you'd want to spend as little time in transit as possible, and that will probably be accomplished by accelerating for half the trip, flipping, and accelerating to match destination velocity. Nevertheless, it IS a valid scenario, and that means that your "one week of maneuver fuel" is going to last longer than that.

On the other hand, power/fuel for OPERATIONS (life support, keeping the computers running, et cetera) IS something that is used continuously, and reasonably measured in terms of duration. About the only way you can reduce this is to shut down the ship and go into low berth (or emergency low berth) and just drain parasitic power to maintain the berths and maybe the computer in standby mode. A good move if you come out of misjump, or if your jump targetting turns out to be so poor that you end up in the outer Kuyper belt or the Oort cloud for your destination system.

(note: I use acceleration/accelerating in the physics sense of a change-in-velocity. Common usage would use 'decelerate' in the contexts that I have you matching the velocity of the destination.)
 
IMO, the "two weeks" is simply a standardized measure of fuel consumption. I lived in Germany for a year. While there, they didn't talk about fuel economy in terms of miles per gallon (or even liters per km). It was how much fuel the car used after travelling 100 km. Same thing, just multiplied by 100.

I think of Traveller's fuel notation as the same concept except that is measuring how many tons of fuel are used after 2 weeks at max speed. If the players are traveling slower or landing on a planet, I'd say the players should get a break and be allowed to consume fuel at a much lower rate of speed.
 
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Simplest fix is to realize that not every single aspect of Classic Traveller is superior to later editions, and that power plants would use kiloliters per year, not dTons per week. Just take your ships and convert power plant fuel tankage to cargo space.


Hans
 
I would suggest ignoring the issue completely. Assume the ship has enough fuel to power it for years. After all, it has a fusion power plant, and the M-drives are powered by the power plant, and a single dton of hydrogen fuel should (if using real-world physics) power the plant for decades. Otherwise for the jump drive, assume that a ship has enough fuel for two jumps.

Fuel should only be an issue, in my opinion, if the GM wants to make it an issue for plot purposes.
 
I did consider having PP fuel as coolant, but I think you can reuse coolant, can't you? So in the end I ditched fusion pps and instead used fission ones for my reaction drive campaign, all fuel is reaction mass, the fission drive replaces fuel at the annual maintenance.

All very real world, but not solving the issue, just ducking out ....
 
IMO, the "two weeks" is simply a standardized measure of fuel consumption. I lived in Germany for a year. While there, they didn't talk about fuel economy in terms of miles per gallon (or even liters per km). It was how much fuel the car used after travelling 100 km. Same thing, just multiplied by 100.

I think of Traveller's fuel notation as the same concept except that is measuring how many tons of fuel are used after 2 weeks at max speed. If the players are traveling slower or landing on a planet, I'd say the players should get a break and be allowed to consume fuel at a much lower rate of speed.
Assuming that the fusion drives in Traveller are efficient enough that the fusion reaction releases more energy than is put in (something we haven't been able to achieve IRL as yet) it still wouldn't consume so much LHyd so rapidly. The hydrogen is not being combusted in a chemical reaction like rocket fuel: it's a fusion reaction, which ought to release a million times more energy per gram consumed than if you were attempting to simply burn it in an oxygen atmosphere.

Robert L Forward once calculated that one would only require about a milligram of antimatter to make it to the stars. Fusion is not that efficient, but it's close. I'd really not worry about refuelling the P-plant and M-drive every two weeks: IMTU, a couple of dtons of LHyd storage should keep a P-plant and M-drive going for years, with breaks only for maintenance - going over the containment system with a nuclear damper, periodic replacement of the beryllium casing and so on.
 
IMO, the "two weeks" is simply a standardized measure of fuel consumption. I lived in Germany for a year. While there, they didn't talk about fuel economy in terms of miles per gallon (or even liters per km). It was how much fuel the car used after travelling 100 km. Same thing, just multiplied by 100.

I think of Traveller's fuel notation as the same concept except that is measuring how many tons of fuel are used after 2 weeks at max speed. If the players are traveling slower or landing on a planet, I'd say the players should get a break and be allowed to consume fuel at a much lower rate of speed.

The European "Standard fuel use" isn't a simple "run 100km" it is a normed test including so many km in the city (50km/h top), overland (100km/h top) and autobahn (130km/h top) with a bit of start/stop cycle. The test is run on a static test stand, not on the real streets. Getting a car to match that number IRL is as likely as winning the german lottery (6 out of 49 + 1 out of 10 = 140 Million to 1). So hopefully that's not the way Traveller handels it. You can't stop over at a fuel station in space.
 
I did consider having PP fuel as coolant, but I think you can reuse coolant, can't you? So in the end I ditched fusion pps and instead used fission ones for my reaction drive campaign, all fuel is reaction mass, the fission drive replaces fuel at the annual maintenance.

All very real world, but not solving the issue, just ducking out ....

You can only reuse it if you can cool it down again. And even then it only makes sense if the gear necessary is rather small. IRL power plants use a secondary open cycle cooling system to cool down/condense the primary operating water (that is heated in the boiler) venting the head as water steam. Ship diesels also use an open cylce cooling system (at least on smaller pleasure boats) dumping the warm water out the side

So dumping the coolant may very well be an option.
 
I would suggest ignoring the issue completely. Assume the ship has enough fuel to power it for years. After all, it has a fusion power plant, and the M-drives are powered by the power plant, and a single dton of hydrogen fuel should (if using real-world physics) power the plant for decades. Otherwise for the jump drive, assume that a ship has enough fuel for two jumps.

Fuel should only be an issue, in my opinion, if the GM wants to make it an issue for plot purposes.

Classic problem: That's a house-rule. Game rules shouldn't need house rules. That's even more true if the rules are the fifth incarnation of a game universe like MGT is. And house rules are the most common reason for endless discussions at the game table. Book rules are less debatable.
 
The European "Standard fuel use" isn't a simple "run 100km".

Just sharing what I experienced. I fully admit that I might not have been fully informed since I was a high school student at the time and everyone considered me less intelligent, since I wasn't perfectly fluent when I arrived. Most of the time, however I was able to understand what they were talking about, even if I could not communicate my thoughts readily.

Game rules shouldn't need house rules.

Yes and no. A game company can come up with a standardized set of rules. But a company cannot anticipate the needs of your exact group vs another group, nor should they. Any company should aim to make the most number of people as happy as possible. Customization to the individual group's needs should be the responsibility of the group. In an ideal world, there would be no need for customization, but we do not live in an ideal world.

Book rules are less debatable.

You have never played Dungeons and Dragons with my friends. I stopped gaming with them because we were unable to spend less than 1/2 our time arguing about something in the rules.
 
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Classic problem: That's a house-rule. Game rules shouldn't need house rules. That's even more true if the rules are the fifth incarnation of a game universe like MGT is. And house rules are the most common reason for endless discussions at the game table. Book rules are less debatable.

I am an intelligent, imaginative person, and I see no reason to be bound to what a book tells me. If you prefer to do something differently to how I would do it, then feel free to do so.
 
I was always under the impression the two weeks was under full power. so jumpwoudl be close to being a free week.
Logically it would be. However, CT rules overlooks this aspect of the situation and require new power plant fuel every four weeks regardless. At least, I think it does; I can't actually recall where, though.

For an armed ship it's even worse. Fuel consumption is effectively based on the assumption that you're firing the weapons 24/7! ;)

EDIT: Firing the energy weapons, of course.


Hans
 
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For an armed ship it's even worse. Fuel consumption is effectively based on the assumption that you're firing the weapons 24/7! ;)

Isn't that what everybody else does? :confused:

And not just energy weapons, I fire full salvos of missiles 24/7 as well from my HG missile bays of infinite reloads...

...but that's another topic entirely :)
 
JTAS # 14, page 25 has an optional HG rule about powering down. A ship can power down to Pn 1 (in which state it can't fire energy weapons and manuevers at 1-G). It consumes fuel as a normal Power Plant 1 would.
 
I am an intelligent, imaginative person, and I see no reason to be bound to what a book tells me. If you prefer to do something differently to how I would do it, then feel free to do so.

Question: If I have to change the book/don't need the book, why buy it in the first place? I pay a company so I DON'T have to spend time house-ruling. Otherwise I could have stopped buying Traveller stuff after MegaTraveller (The German variant of Clunky was even worse than the US version and that was baaad IMHO)

And as soon as you play at a convention etc. House rules will come back and bite you in the lower back. Same with new players in the group, new groups etc. "By the book" is the way and a game should deliver if the company want's my money (Obviously Mongoose does not get mine)
 
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