Emergency Beacon Detection Range

I had read p18 of HG to mean the fuel requirement was per 2 weeks for all plants. This is not how it was in CRB and checking not how it is implemented in Small Craft so this is likely an error on my part. I think the formula was still incorrect, but my correction was also a factor of two out.

However, back at the original thread, if you get 4 weeks fuel out of a particular fuel reserve rather than 2 weeks, the Stirling plant is even more of a dog as you can double the endurance of my conventional design.
 
I had read p18 of HG to mean the fuel requirement was per 2 weeks for all plants. This is not how it was in CRB and checking not how it is implemented in Small Craft so this is likely an error on my part. I think the formula was still incorrect, but my correction was also a factor of two out.

However, back at the original thread, if you get 4 weeks fuel out of a particular fuel reserve rather than 2 weeks, the Stirling plant is even more of a dog as you can double the endurance of my conventional design.
It's the fuel storage that makes yours unsuitable. I can get 1,300 weeks of coverage from a 12 power point, 2-ton Sterling fission plant. The fuel requirements for yours is 26 tons for a 3-ton hull. It's the same for a 20-ton hull.

I'm sure that would drop as I lower the power points required. Let me look. Dropping the power requirement to .8 (.3 for the pod and .5 for the AutoBerth) I get this on the fuel requirement. 13 tons. So, not better.

1748716397504.png

The Power Plant.

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Which book is the sterling fission plant in?

I ask because someone who knows a bit about nuclear fission reactors should be asked about the fuel use rates of fission reactors in MgT.
It's in The Spinward Extents. Here is the writeup.

And this also mentions batteries used for jump. I missed that. ;)

1748716592614.png
 
So yet again technology is hidden in supplements rather than being in the core shipbuilding or vehicle book. This is getting a bit repetitive now.

Also note the author can not spell "Stirling", which I copied and didn't edit until I looked it up on wiki. Nor does the author understand half life.

The power output will decline over the lifetime of the engine, if it can maintain 3EP for 10 years then start degrading then it should take a lot longer than one year to lose the next EP. (note its half life is 17 years and is should drop from 3 to 2.9 and so on over time)
 
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So yet again technology is hidden in supplements rather than being in the core shipbuilding or vehicle book. This is getting a bit repetitive now.
Agreed. It's an intent to make a compendium to consolidate what's out there. And of course, this was written for HG'16, so it might need tweaks.
Also note the author can not spell "Stirling", which I copied and didn't edit until I looked it up on wiki. Nor does the author understand half life.
My bad on the spelling. Hard enough to keep my brain switching between American and British English, and then dealing with the Scottish...
but that's no excuse.
As for half-life, the half-life of the fuel is not the issue; it's not a plutonium RTG. Thorium-232 has a half-life longer than the current age of the universe. It's a degradation of the sealed operating unit that eventually causes it to become less efficient. In theory. Nobody has actually ever built one. Or at least not an unclassified one.
The power output will decline over the lifetime of the engine, if it can maintain 3EP for 10 years then start degrading then it should take a lot longer than one year to lose the next EP. (note its half life is 17 years and is should drop from 3 to 2.9 and so on over time)
See above.
 
This is now getting ridiculous, all of those options should be in High Guard or at the very least included in JTAS as HG updates until the next revision of HG is necessitated by the sheer amount of supplementary rules hidden away in adventures and supplements.

Or better still made available in a free pdf HG update as these new rules are released into the wild.

I know I am never going to see a time where Traveller authors have to use the rules as written, but it makes it very difficult to have discussions on these forums when you lack vital rules.
 
My bad on the spelling. Hard enough to keep my brain switching between American and British English, and then dealing with the Scottish...
but that's no excuse.

@Arkathan now knows to use the right spelling in the updated sheet.

As for half-life, the half-life of the fuel is not the issue; it's not a plutonium RTG. Thorium-232 has a half-life longer than the current age of the universe. It's a degradation of the sealed operating unit that eventually causes it to become less efficient. In theory. Nobody has actually ever built one. Or at least not an unclassified one.

So, adding in self-maintenance enhancements would increase the life of the unit? That could be a thing.
 
Agreed. It's an intent to make a compendium to consolidate what's out there. And of course, this was written for HG'16, so it might need tweaks.

My bad on the spelling. Hard enough to keep my brain switching between American and British English, and then dealing with the Scottish...
but that's no excuse.
As for half-life, the half-life of the fuel is not the issue; it's not a plutonium RTG. Thorium-232 has a half-life longer than the current age of the universe. It's a degradation of the sealed operating unit that eventually causes it to become less efficient. In theory. Nobody has actually ever built one. Or at least not an unclassified one.
Why would this sealed unit degrade any faster than real world sealed units? Many radiothermal generators have been built, and successfully utilised in spacecraft. It is the half life of the radioisotope that reduces efficiency until the critical threshold of operation is passed.

Thorium as a nuclear fuel must be converted into uranium by neutron bombardment, which means you need a plutonium or uranium component along for the ride.




 
Why would this sealed unit degrade any faster than real world sealed units? Many radiothermal generators have been built, and successfully utilised in spacecraft. It is the half life of the radioisotope that reduces efficiency until the critical threshold of operation is passed.
The intent was to makes something more powerful than an RTG, which would have minuscule power (0.01??) on a starship scale.

It was supposed to be a niche thing for a niche star system, and would probably be replaced by a basic fusion plant at TL8. And I see I wrote in 'charging jump drives with batteries', which may or may not be a thing. Oh well. Probably just deprecate that whole thing. The main point was to bypass the vague clarity on whether a fission drive needed fuel every 4 weeks, which... needs to be finessed. There are pre HG'22 solar power rules in there too that are essentially deprecated
 
The intent was to makes something more powerful than an RTG, which would have minuscule power (0.01??) on a starship scale.

It was supposed to be a niche thing for a niche star system, and would probably be replaced by a basic fusion plant at TL8. And I see I wrote in 'charging jump drives with batteries', which may or may not be a thing. Oh well. Probably just deprecate that whole thing. The main point was to bypass the vague clarity on whether a fission drive needed fuel every 4 weeks, which... needs to be finessed. There are pre HG'22 solar power rules in there too that are essentially deprecated
To be clear, I like this niche power source. It does need a place in High Guard. Unless the fuel requirements for a fission/fusion plant go down.
 
The intent was to makes something more powerful than an RTG, which would have minuscule power (0.01??) on a starship scale.

It was supposed to be a niche thing for a niche star system, and would probably be replaced by a basic fusion plant at TL8. And I see I wrote in 'charging jump drives with batteries', which may or may not be a thing. Oh well. Probably just deprecate that whole thing. The main point was to bypass the vague clarity on whether a fission drive needed fuel every 4 weeks, which... needs to be finessed. There are pre HG'22 solar power rules in there too that are essentially deprecated
I completely agree on the need to revisit a lot of these things with real world science and engineering being the starting point and then the science fictional advances up the TL scale.

One of the goals of the kilopower system is to provide the power needed for manned missions. A big issue with MgT is the lack of a clear definition of what an EP is.

As to power - 5W per kg - a 14 cubic metre or one ton unit is going to mass ~140,000kg, which mans a ship ton of rtg is generating ~700kW
the kilopower stirling/uranium fission generator is 1kW is 130kg, while 10kW is 1500kg.

Using those as ship scale you are looking at ~1MW per ship ton.

So how many MW is an EP in MgT?
 
To be clear, I like this niche power source. It does need a place in High Guard. Unless the fuel requirements for a fission/fusion plant go down.
The fuel requirements for fission power plants as they stand are several orders of magnitude beyond realistic. In this case real world fuel use is much less than in MgT (need to go check AEH for 2300...)
 
So how many MW is an EP in MgT?
There isn't and probably won't ever be an official answer for that, but my back of the envelope working assumption, carried forward from MT days and made even vaguer by time, is ~10-15MW per power point.

But using that sort of number causes all sorts of problems. Might be more of a logarithmic value below 1 PP to 'account' for solar, but that causes an entirely different scaling headache. So, no. I don't think there will ever be an official MgT2 answer to that question.

It's easier to work with power at robot scales, sort of possible at vehicle scales, but without being built from ground up like your tag line says, any number we pick will break something. And as soon as you pick something, you have to consider that some smart ass (probably me) will build a 'perpetual motion' machine by using grav plates and the guts of a hydroelectric dam to generate more energy out of a system than what it takes to run it (which, of course is exactly what a fusion plant is (because, fusion), but the grav-bootstrap-turbine is essentially a primitive.. gravitic power plant? - Yes, you could probably carefully construct the power inputs, field strength and other limitations of grav plates and thrusters to make it infeasible, but you'll probably make it infeasible to make the spaceship fly using as a result of those constraints. Consistency is not a requirement for Space Opera... which is essentially what Traveller's historical tech landscape derives from.
 
It's the fuel storage that makes yours unsuitable. I can get 1,300 weeks of coverage from a 12 power point, 2-ton Sterling fission plant. The fuel requirements for yours is 26 tons for a 3-ton hull. It's the same for a 20-ton hull.

I'm sure that would drop as I lower the power points required. Let me look. Dropping the power requirement to .8 (.3 for the pod and .5 for the AutoBerth) I get this on the fuel requirement. 13 tons. So, not better.

View attachment 4991

The Power Plant.

View attachment 4992
Terry, please stop using the flawed spreadsheet (the fuel consumption is definitely out of whack) to refute my point.

Please look at the words in the rule books and use a pencil and paper instead. The statement that the fuel requirement for a 3 ton vessel is the same as a 20 ton vessel shows that the spreadsheet does not work for this low power use case.

For this low end usage the rounding errors introduced in the spreadsheet swamp the actual numbers. It is rounded to 2 decimal places this is an artifact of the spreadsheet not a rule in the game. You are permitted to have fractional tons of power plants.

Tell me which specific statement below that you disagree with once you have looked at the book and done the math.

a) 2 low berths in a 3 ton non-gravity hull on emergency power uses 0.35 power.

b) 0.35 power can be generated by 0.0175 DTons of TL15 fusion plant.

c) 0.0175 DTons of fission power plant uses 0.00175 Dtons of fuel per 4 weeks.

d) 1 DTon of fuel will therefore last 43 years.
 
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Terry, please stop using the flawed spreadsheet (the fuel consumption is definitely out of whack) to refute my point.

Please look at the words in the rule books and use a pencil and paper instead. The statement that the fuel requirement for a 3 ton vessel is the same as a 20 ton vessel shows that the spreadsheet does not work for this low power use case.

For this low end usage the rounding errors introduced in the spreadsheet swamp the actual numbers it is rounded to 2 decimal places so the lowest you go is 0.02 this is an artifact of the spreadsheet not a rule in the game. You are permitted to have fractional tons of power plants.

Tell me which specific statement below that you disagree with once you have looked at the book and done the math.

a) 2 low berths in a 3 ton non-gravity hull on emergency power uses 0.35 power.

b) 0.35 power can be generated by 0.0175 DTons of TL15 fusion plant.

c) 0.0175 DTons of fission power plant uses 0.00175 Dtons of fuel per 4 weeks.

d) 1 DTon of fuel will therefore last 43 years.

Math is hard, he whines...

a) 1 AutoBerth = .5 power, 3 tons no gravity = .3 power. Total= .8 (I'm powering it all)

b) .8 power (what the sheet is using) can be done with .04 tons of TL15 Fusion.

c) .04 tons of TL15 fusion power requires .004 tons per 4 weeks.

d) 1.3 tons of fuel for 1300 weeks (which was my comparison point. My belief is that the small craft rules for fuel only removed the 1 ton minimum, so I think this is correct.

Well, it sure seems like the math is wrong in the sheet. Damn.
 
But using that sort of number causes all sorts of problems.

I’m struggling to understand why defining a point of Power is such an issue. It needn’t be real-world compliant- although that would certainly be cool - but really it only needs to be internally consistent.

And then Time/Duration/Working Life, whatever.

So, for an overly simplistic example, let’s say the Voyager TL6 RTG creates 0.001 Power per week. It’s been operating for 50 years - 2,600 weeks. It is now approaching the end of its useful life cycle. It weighs 10kg (does it? I don’t know).

So there’s your metric. A Standard TL6 RTG can output 0.001 Power per week for 50 years and displaces 0.01 dtons. After that it must be replaced.

So a Standard TL6 RTG displacing 1 dton can supply 0.1 Power per week. Normalize shipboard Power costs to be weekly and things start to make sense. Weapons and Screens could be single-use costs or part of the weekly overhead.

TL7 Fission = 0.1 Power per ton per week, 50 years then replace
TL8 Early Fusion = 1 Power per ton per week, 1 year then refuel
Whatevs, you get the point.

For the record, Geir, I’m a huge fan of yours, from all the way back when you were posting Aslan ship designs built in spreadsheets. Please don’t take this as argumentative but rather… a prod to the imagination. 🙃
 
Math is hard, he whines...

a) 1 AutoBerth = .5 power, 3 tons no gravity = .3 power. Total= .8 (I'm powering it all)

b) .8 power (what the sheet is using) can be done with .04 tons of TL15 Fusion.

c) .04 tons of TL15 fusion power requires .004 tons per 4 weeks.

d) 1.3 tons of fuel for 1300 weeks (which was my comparison point. My belief is that the small craft rules for fuel only removed the 1 ton minimum, so I think this is correct.

Well, it sure seems like the math is wrong in the sheet. Damn.
Yep a quick dip test shows it seems to be a factor of 8 out (at least some of the time). All the hidden values are correct until that massive formula in D11 and that just screws everything up.
 
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