House Rules - Fixing Ship Fuel Operational Times

[Egil Skallagrimsson]

Fusion power plants would still be able to produce variable output. Increased demand for when the power is needed, for instance to operate the big weapons, and reduced demand when the ship's just coasting in sublight, running on basic life support with passive sensors.

They'd be able to intensify or loosen the pinch field - presumably a combination of grav and MHD fields - to increase or decrease the efficiency of the ongoing fusion reaction, a bit like the choke in an internal combustion engine. And if they needed to get a bit more out of the plant - a bit of overclocking, as it were - they could inject some deuterium and lithium ions into the mixture. The equivalent of activating a shot of pressurised nitrous in a performance internal combustion engine.

Good bit of handwaving , and you may be proved right sometime in the next three centuries, or perhaps not. Assumptions of easily variable, and controllable, output from small fusion plants, which so much of this thread has been based upon, are just guesses as to how a fictional technology may work.

Like some of our other game assumptions, e.g. controllable grav plates, FGMPs and psionic powers, there is nothing necessarily wrong with the ideas in MgT, which is where I tend to part company with posts which argue for greater "realism" based on their, unprovable, assumptions. Especially when those assumptions seem to need more book keeping to support them.

Egil

 

[Egil Skallagrimsson]

I don't honestly believe they thought of scenarios where the ship would have to spend extended periods in-system, or where the ship was at risk of running out of fuel before it could reach planetside.

The CRB author would have to comment on his thinking regarding your first point above, but as it is quite clear that there will be a large number of spaceships using m-drives that are not jump capable, and are likely to be hauling cargo and passengers in-system, then perhaps he was happy with the fuel consumption figures for ships which would only travel in-system.

Regarding the second point, "inaccurate jumps just dump the ship somewhere I the inner system requiring a long space flight", I am always used this to mean a space flight of a few days, so the typical ship with 14 days fuel will still be ok, 7 days in jump, if inaccurate, you still have 7 days fuel to get to the starport or GG.

Egil

 

[Egil Skallagrimsson]

Nor that so many people would obsess over the issue so much.

:lol: :lol:

 

[alex_greene]

The whole thing can do with being reviewed anyway. It's not just the issue of fuel: there could be commercial fusion plants, designed to power ships with a heavy thrust output such as tugs, as well as fusion plants designed for endurance operations - such as the Watchdog-class picket ships designed to hang around at the edge of blockaded solar systems scanning for in-system activity.

There could be fusion plants built to power up performance M-drives, for instance in sublight racing yachts built for in-system races and regattas.

And then there could be power plants intended for use in vessels such as police cruisers, where sheer power is needed for thrust and manoeuvrability.

 

[phavoc]

It's not about logic, it's about playability. I don't see the supplements you list as adding "complexity" at all, just different options.

Background and explanation isn't a bad thing. I think a number of people have agreed that isn't the case with them.

For those who feel their gaming will be enhanced by more book keeping, then there are other versions of trav, or write your own.

Why does it seem that whenever somebody questions the order of things the response of "go away - we don't want your stinking questions" come up? It would be just as rude (but totally applicable) to tell you to go away too with your response if you don't like the thread.

Just another thought about fusion power plants in MgT, we seem to be working on the assumption (and, of course, these are fictional assumptions about a technology which doesn't exist and may never exist in this form, or even at all) that they run a bit like petrol engines, and the more power we need, the more fuel we burn. What if they are much more binary, essentially off, no power, no fuel consumption, or on lots of power (much of which might have to be vented if there is not immediate use for it), steady fuel consumption?

Today, with fission power, you can adjust the power output and extend/reduce the life of your fuel, right? It's true for civilian power plants as it is for military ones. The book just plain got it wrong with the explanation of nuclear power as it exists today. Since we don't have working fusion tech, contragravity, jump drives, or are flying amongst the stars, I'm sure most players are well aware that this is a science-fiction game we are playing. I'd like to point out that 1/3rd of that label is "science". So any person wanting to apply science to their game is perfectly within the defined context. "Fiction" comes around when you start talking about uplifted dolphins, ancient beings and kitty-cats and doggies with nukes and starships. The "game" is where you want to combine the former two and still have fun.

This thread was started to discuss the never-ending discussion regarding the apparently huge fuel consumption that entails powering a Traveller ship's fusion reactor. Exactly why this is a big deal has to do with one thing - tonnage. A different fuel burn rate means you have more tonnage to play with with which to do other things.

If you (or anyone else - I don't want you feel I'm singling you out, just using your quote of my quote) are fine with the rules as they are, then feel free to ignore the thread. If you would like to be a useful contributor, please share with the rest of us your thoughts. But if you only want to tell the rest of us to "just accept it or go find another game", kindly don't respond. Or start your own thread where you can discuss why exactly the game is perfect just the way it is and there should never,ever be a discussion about a rule, a deckplan or the underlying reasoning for such things.

And do please keep in mind the "you" is the euphemistically "you" - NOT any one individual.

 

[Condottiere]

I see starship travel and maintenance as one of the central features to Traveller. much as you should keep track of how many bags of oats you plan to take along on a D&D outing to feed the ponies.

 

[Condottiere]

1. A thought occurred to me: continuously adjusting the power plant to generate the electricity needed to run the ship systems that are currently active, may cause a faster component failure rate, and therefore be more expensive to maintain.

2. Speaking of failure rates, when do starships need to be docked for an overhaul?

 

[leopard]

Even back 20 odd years ago when I was designing ships on a semi regular basis (high detail if a player would ever get near the bridge, less so for NPC type ships where I didn't care how many staterooms they had, just drives and weapons) I used a basic spreadsheet - not during the game but during the design phase.

Ships then had several power levels, often in the end slightly fudged so they became simple multiples of endurance, you had a 'cruise' power setting, 1-2G from the drives (even on craft that could do more), all non combat systems - that was the baseline, you had 30 days of that. Maybe 1-2 days of 'all systems at the red line' on top of that, a 'hotel' loads setting with the drives shut down, used in jump space or on a planet. Aimed for circa 90 days of that as a minimum, so 1 day of cruising gave you three days of hotel. Worked out your 'emergency' endurance, basically life support and radios, that tended to be a very long time. And if you only power life support to part of the ship (and turn the gravity off) you can run that on emergency batteries for a while.

Point is, you know this when you build the ship, so when the players end up in the middle of nowhere they have a rough guide from how many days cruising to how long they have to solve the problem - e.g. thrust for a day or so then power down and cruise the old fashioned way.

Exact details are up to the GM, as the GM decides exactly where they are, if you want it to be 'close' to running out by the time they find safety then by a miracle thats what happens. If the players get lucky with an ingenious plan there will be just enough fuel left for it to work..

I like the level of detail MT brought, Hard Times especially, but never let it get in the way of the story. If the players needed to be short on fuel then the power plant started to play up and burn more than usual, just enough more for the story to work. Most players get used to this and see whats happening, so on occasion you throw a spanner in without a specific plot point - if nothing else its a good way to grow engineering skills investigating and a way to burn excess cash fixing things.


As for the practicalities of the design.. in a spreadsheet have a column for "power level" as a percentage, multiple fuel or power by that for that power setting and you have an easy way to turn the ships weapons into dead weight. I had four such settings, easy to have more.

 

[Reynard]

Here's a slightly relevant question; do modern nuclear powered vessels, namely ships, run at full power? Does the power plant generate a certain amount of that goes to the engine to move the ship and it's the engine that determines how much power is needed for various speeds while the power plant also sends energy to other systems.

Naval vessels have an optimal cruise speed which, I believe, is the most energy efficient and runs at this level of power the majority of time.

No up on it too well but I think any nuclear power plant adds and subtracts control rods to respectively lower and raise power generation but that is fission. I am assuming a fusion plant adjusts power output by the rate of injected fuel so it too doesn't run binary - full power or no power. Both types probably run at an optimal level during the task the majority of its operation time and emergency conditions don't last long enough to be sufficient drains on the fuel supply without also damaging the plant.

 

[leopard]

Did wonder on adding an efficiency curve, sort of like running at half power uses 75% of normal fuel etc. the nominal output level being the most efficient for that drive. you can then get +10% power for +25% of fuel etc, for a while

 

[Egil Skallagrimsson]

For those who feel their gaming will be enhanced by more book keeping, then there are other versions of trav, or write your own.

Why does it seem that whenever somebody questions the order of things the response of "go away - we don't want your stinking questions" come up? It would be just as rude (but totally applicable) to tell you to go away too with your response if you don't like the thread.
....
If you would like to be a useful contributor, please share with the rest of us your thoughts. But if you only want to tell the rest of us to "just accept it or go find another game", kindly don't respond.
....
And do please keep in mind the "you" is the euphemistically "you" - NOT any one individual.

Well, as the euphemistic "I", or not, while this is still on a public board, then there is no reason for me not to post. You seem to have got rather tetchy about some responses, but they were meant with good intentions, I don't think anyone has suggested your questions "stink", to quote you, or have been as negative as you suggest. The mentions of other systems were not intended to affront, but to point out that, while one of the advantages of MgT is its simplicity, there are other alternatives which will meet the interests and enthusiasms of different players. And that is no bad thing.

It is interesting that in one sense you feel you are correcting what you see as errors in the game system, but you don't want people who don't share your perspective to respond. The title of the thread really says everything, "fixing", but you seem unhappy when it is suggested that not everyone sees this as "broken".


Egil

 

[CosmicGamer]

Why does it seem that whenever somebody questions the order of things the response of "go away - we don't want your stinking questions" come up? It would be just as rude (but totally applicable) to tell you to go away too with your response if you don't like the thread.
....
If you would like to be a useful contributor, please share with the rest of us your thoughts. But if you only want to tell the rest of us to "just accept it or go find another game", kindly don't respond.
....
And do please keep in mind the "you" is the euphemistically "you" - NOT any one individual.

It is interesting that in one sense you feel you are correcting what you see as errors in the game system, but you don't want people who don't share your perspective to respond. The title of the thread really says everything, "fixing", but you seem unhappy when it is suggested that not everyone sees this as "broken".

As I've said before, when comments lean toward "it's broke" then it implies that the author, Mongoose, Mark, and anyone who plays by the rule is wrong. It's natural for people to want to explain their positions.

There shouldn't be issues when someone says they don't like a rule, or don't understand a rule, and suggest alternatives and look for feedback and suggestions. People should be able to play any way that's fun for them. I'm open minded and can jump right in and help with an alternative set of rules even if I'm fine with the original and would never use the alternative. I'd still question why the changes were needed. The reason for the change helps determine what needs to be done. Often I can come up with options that still fall within all the rules.

For example, if the main issue is that someone wants ships to have longer operational range then simply consider the standard ship designs as standard are more for the core worlds where there is lots of ship traffic and AAA ship services. Ships on the raggedy edge may be more likely to use custom designs that include larger fuel capacities or modified standard designs.

For example, if the main issue is that someone wants to reflect a more realistic, but more complicated and detailed power consumption it is probably a waste of time discussing the Mongoose rules and seams good advice, to me, suggesting alternative rules that may be more suitable or a better starting point for reference when creating custom rules.

 

[Condottiere]

My opinion on this particular issue is that you have to thread a path between over complicated and handwavium. We're living in a technological society, and Traveller is an extrapolation of that, so we tend to be a bit more skeptical when certain aspects don't quite make sense from our current perspective, which hurts our ability to immerse ourselves to enjoy that universe.

It's also human nature to try to go for a solution that is validated by an authority; which tends to mean for me I'd try to adapt an existing rule from a published product, rather than just make one up.

 

[Jame Rowe]

I would call this house-rules-MGT but I use a variation on the fuel rules in Compendium 1, where the power plant endurance times are for TL 8 plants and doubles-or-so per TL. I'm starting to think of triples-or-so per TL instead, but it's the same concept.

 

[phavoc]

It is interesting that in one sense you feel you are correcting what you see as errors in the game system, but you don't want people who don't share your perspective to respond. The title of the thread really says everything, "fixing", but you seem unhappy when it is suggested that not everyone sees this as "broken". Egil

Yours was the, I think, third comment in relation to "if you don't like MGT rules, go find another ruleset". Since yours was the last in that thread I quoted you.

I responded to a thread about fuel operational times. I have no issue with someone arguing a different perspective. That's what we're here for right, sharing our opinions? But I did (and do) take issue when someone suggests that the rule isn't broken (an opinion, no issue there) AND essentially tries to shut down the argument by suggesting they leave the game system alone and go find another that better suits their ruleset desires. That's not an argument at all.

And you are quite correct to state that for some it's not an issue at all. Good for them! It's easy enough to state that, and some did.

I don't always agree with others, but I never tell them to go find another game. Heated discussions? Fine. Disagreements? Fine again. But there's no reason to try and shut down the discussion by telling those who disagree to go and find another game.

 

[phavoc]

Here's a slightly relevant question; do modern nuclear powered vessels, namely ships, run at full power? Does the power plant generate a certain amount of that goes to the engine to move the ship and it's the engine that determines how much power is needed for various speeds while the power plant also sends energy to other systems.

Naval vessels have an optimal cruise speed which, I believe, is the most energy efficient and runs at this level of power the majority of time.

No up on it too well but I think any nuclear power plant adds and subtracts control rods to respectively lower and raise power generation but that is fission. I am assuming a fusion plant adjusts power output by the rate of injected fuel so it too doesn't run binary - full power or no power. Both types probably run at an optimal level during the task the majority of its operation time and emergency conditions don't last long enough to be sufficient drains on the fuel supply without also damaging the plant.

There isn't a naval ship built that runs continuously for it's reactor's lifetime. The Nimitz class carriers are expected to have a 50 year lifespan. The reactors (two of them, putting out about 200Mw) are expected to last for about 1 million miles. To the best of my knowledge a RCOH (refueling and complex overhaul) is only supposed to happen once in a lifetime for each of the Nimitz class. Since the reactors have a mileage associated to them, they could conceivably come in for the 3-4yrs process earlier than necessary, but the Navy typically tries to only have one carrier undergoing RCOH at a time, since it's totally out of commission. The rest of the time they would go through standard repairs or heavier refits.

Carriers run at higher speeds more often since they need to launch aircraft. Submarines on the other hand, don't need to run at full speed as much. Though their reactors are smaller, and the length of time the fuel can last can be tinkered with by increasing the enrichment levels.

RTG's are a different beast though. They can last for decades (and have) on deep-space probes. The longest lasting ones use plutonium and the heat they generate is converted by a thermocouple into electricity. But RTG's put power out in the watt range, far too small to be useful industrially. Plus they decay at a regular rate, so their effective lifespan can be calculated before you put it together. I suppose you could have hundreds, or thousands of the buggers for power, but you can't ever turn them 'off' without destroying them. So what works well for a beacon or something you rarely ever need to maintain doesn't work so well for ships or vehicles.

 

[Egil Skallagrimsson]

But I did (and do) take issue when someone suggests that the rule isn't broken (an opinion, no issue there) AND essentially tries to shut down the argument by suggesting they leave the game system alone and go find another that better suits their ruleset desires. That's not an argument at all.

I honestly don't believe that anyone was trying to shut down the discussion. It is simply the case that these issues have been discussed, and rules created for, in other versions of Trav. Personally I see no reason why a GM could not use those parts of MgT which they think work well, and bolt on parts of MT, T4, whatever which they think are better, to cover particular aspects of the game (e.g. fusion fuel usage in different circumstances). When some of us are suggesting other systems, it is not to shut down the conversation, it is just to be helpful, trying to assist in re-inventing the wheel.

Egil

 

[alex_greene]

Everyone, can we focus on the rule, please, and not the name calling and muck slinging?

 

[Condottiere]

We know options are available, including Mr. Fusion.