HG 2e Small Craft requiring 4 weeks of fuel

Power plant fuel gets rounded up.

Say power plant size for 4 weeks is 1.2 tons, that gets rounded to 2 tons for 4 weeks of operation, so 4 tons would be 8 weeks of operation and so forth.

If it's .4 tons, that gets rounded up to 1 ton for 4 weeks of operation.
 
Morning PST AndrewW,

AndrewW said:
Power plant fuel gets rounded up.

Say power plant size for 4 weeks is 1.2 tons, that gets rounded to 2 tons for 4 weeks of operation, so 4 tons would be 8 weeks of operation and so forth.

If it's .4 tons, that gets rounded up to 1 ton for 4 weeks of operation.

Thank you for the clarification could you please provide the source that requires fractional tank sizes over 1 d-ton are rounded to the next size.

The formula of Power Plant Size x 10% calculates the fuel tank sized needed for 4 weeks of operation.

TL-12 1 d-ton Fusion Power requires 1 x 10% = 0.1 d-ton of fuel to operate for four weeks. Unfortunately, the minimum fuel tank size for a power plant of 1 d-ton indicates that the same power plant installed in a small craft consumes ten times fuel as a 10 d-ton power plant.

The above does not make sense to me especially for small craft like the light fighter that are designed to operate 24 hours. Heck 1 d-ton of fuel for a 6 hour round trip for a planet's surface to orbit does not make much sense either.

I will admit the in some ways the MgT HG revision appears to have a lot less impact than the one for CT so I guess I will live with the current rules when I submit something to Mongoose Publishing.

Thank you again AndrewW for your time.
 
Hello Andrew,

AndrewW said:
snrdg121408 said:
Thank you for the clarification could you please provide the source that requires fractional tank sizes over 1 d-ton are rounded to the next size.

Other power plants require fuel tankage equal to 10% of their size (rounding up, minimum 1 ton).

Again thank you for the clarification my understanding is that when the calculated fuel tank size is < 1 d-ton round to 1 d-ton.
 
snrdg121408 said:
Again thank you for the clarification my understanding is that when the calculated fuel tank size is < 1 d-ton round to 1 d-ton.

One ton is the minimum, but it's always rounded up to the next ton.
 
You can commingle power plant(s) and jump capacity fuel requirements, so it's really only an issue for smallcraft, especially light fighters.
 
AndrewW said:
One ton is the minimum, but it's always rounded up to the next ton.

For the most part, I really really like the HG design sequence. But this annoys me.
I house rule it to allow decimal fuel tonnage. In fact I allow 1 week increments instead of the relatively coarse 4 week chunks.

I haven't designed any small craft yet, so not sure of the implications, but I can imagine i could find a better use for that fractional ton...
 
Morning PST AndrewW and Condottiere,

For a bit more clarification from my side of things AndrewW the text of "Other power plants require fuel tankage equal to 10% of their size (rounding up, minimum 1 ton)." does not suggest that all power plant tank sizes are being rounded up. Had the text been "Other power plants require fuel tankage equal to 10% of their size rounding up (minimum 1 ton)." I would have understood that power plant size calculation rounds the fractional amounts.

Condottiere reminded me that my main focus about small craft requiring 4 weeks/1 d-ton of fuel does not make sense was started over the TL-12 10-dton Light Fighter use of a cockpit that has only 24 hours of life support requiring a fuel tank size of 1 d-ton.

I can understand star ships being required to carry a minimum fuel requirement since the vessel travels interstellar distances and upon arrival in the next star system transits from were it dropped out of jump to a gas giants and/or the local star port.

System ships traveling between points within a planetary system having a minimum fuel requirement also makes sense.

Small craft operational endurance is usually shorter than either a star ship or system ship and having a minimum fuel requirement again makes sense.

What does not make sense is that they all have the same minimum fuel tank size that provides an operational period four weeks.

I agree with four weeks or 1 d-ton of fuel for a star ship since they spend an average of one week in jump space and then have a variable amount of time to transit between points in the destination planetary system.

A system ship on the other hand is traveling within a planetary system and at 1G requires 7.3 days to cover 1,000,000,000 km. Why does the system ship require 1 d-ton or 4 weeks of fuel?

The light fighter's cockpit has life support equipment that has a maximum duration of 24 hours That is extended by the crews vac suits to 32 hours. Adding extended life support pushes the fighter's endurance another 12 hours for a total of 44 hours. Why does this spacecraft need 4 weeks of fuel?

Why does a small craft that is shuttling passengers and cargo between the High Port and Low Port require 4 weeks of fuel?

I recognize that one reason for the 1 d-ton power plant requirement for all spacecraft is make the design system less complex while making individuals like me wonder why a small craft or system ship needs the same fuel requirement as a star ship.
 
Morning allanimal,

allanimal said:
AndrewW said:
One ton is the minimum, but it's always rounded up to the next ton.

For the most part, I really really like the HG design sequence. But this annoys me.
I house rule it to allow decimal fuel tonnage. In fact I allow 1 week increments instead of the relatively coarse 4 week chunks.

I haven't designed any small craft yet, so not sure of the implications, but I can imagine i could find a better use for that fractional ton...

One implication is a small craft with life support for 24 hours running around with 1 d-ton of power plant fuel allowing the plant to operate 4 weeks.

MgT HG 1e copyright 2008 p. 59 has rules concerning small craft & fuel requirements which HG 2e left out. In this case evoking the HG 1e rules in my opinion would not be a house rule.
 
But it's also not official HG2e. HG1e had it's day, HG2e went through extensive beta and somehow no one seem to question the minimum rule and it is now 2e canon. Anything outside the 2e rulebook is house rules which Traveller Rule Zero says is all right. Now go build that fraction fuel tank fighter.
 
The issue is less about house rules, rather that it illegalizes such a design if it's openly presented.

And there seems to be no rational, game or otherwise, compared to engineering, where economy of scale is relevant.
 
Hello Reynard,

Your are correct that MgT 1e rules are not valid in MgT 2e anymore than MgT 2e rules are valid in MgT 1e. Every MgT 1e design is pretty much invalid in MgT 2e. Yeah, I know go with one or the other rule set.

According to MgT HG 1e fractional fuel tank size for star ships and system ships round up. Small craft fuel tank size on the other hand took into account that they did not need to function for 4 weeks in HG 2e or 2 weeks in HG 1e.

I repeat that designs being submitted to Mongoose Publishing with the intention of having them as a standalone or part of another product or a publication like Freelance Traveller should follow the published rules.

Material being used and approved by the Referee and players can be modified to suit the game setting.

I hope that this discussion may persuade the Powers That Be to re-introduce the HG 1e Small Craft & Fuel Requirements as an option in some future product.

If at some point, which does not look to be any time soon, I think I have a good handle on the design rules I might submit a design to Mongoose or even Freelance Traveller.

Thank you and everyone here that has provided a response to this and other topics I have submitted.
 
Hello all,

Here is the recap for Power Plant fuel requirement as I understand them from this discussion.

Power Plants
Spacecraft using Chemical power plants require 10 d-tons of fuel per ton power plant for an operational period of 2 weeks

Spacecraft using a Fission, Fusion, or Antimatter power plant calculate fuel tank size using the formula of round up(Power Plant Size in d-tons x 10%,0) which provides an operational period of 4 weeks.
 
1. I'd want a tonne of lead surrounding fissionable material.

2. There's no caveat that says you'd need more than a tonner tank for chemical fuel.

3. There's no reason given you couldn't have a milk carton sized fuel container for a fusion plant; it may even simplify refueling.
 
Condottiere said:
1. I'd want a tonne of lead surrounding fissionable material.

2. There's no caveat that says you'd need more than a tonner tank for chemical fuel.

3. There's no reason given you couldn't have a milk carton sized fuel container for a fusion plant; it may even simplify refueling.

Lead? A few centimeters of collapsed matter would do a much better job. Lead is so 21st century!

You'd have to calculate the operational time of your chemical power plant using a single D-ton of fuel. If it was of any size it would be a very short duration.

The rate Traveller power plants consume fuel, the milk carton of hydrogen wouldn't last very long.
 
Morning Condottiere and phavoc,

Condottiere said:
1. I'd want a tonne of lead surrounding fissionable material.

The Traveller Universe technology apparently has developed material that is much lighter and more effective than lead.

2. There's no caveat that says you'd need more than a tonner tank for chemical fuel.

MgT HG 2e p. 17: "Chemical power plants require 10 tons of fuel per ton of power plant for every two weeks of operation."

If spacecraft with fission, fusion, and antimatter power plants require a 1 d-ton as established in this discussion then the text above clearly states that the standard chemical power plant fuel tank is 10 d-tons or modified by the Primitive & Advanced Spacecraft Options for fuel efficiency or inefficiency modifiers to be a legal design in MgT HG 2e.

3. There's no reason given you couldn't have a milk carton sized fuel container for a fusion plant; it may even simplify refueling.

To be legal under the MgT HG 2e rule set the minimum size power plant fuel spacecraft require at minimum a tank of 1 d-ton. and there are no fractional amounts per the text of Power Plant Size x 10% (rounding up, minimum of 1 ton).

phavoc said:
Condottiere said:
1. I'd want a tonne of lead surrounding fissionable material.

2. There's no caveat that says you'd need more than a tonner tank for chemical fuel.

3. There's no reason given you couldn't have a milk carton sized fuel container for a fusion plant; it may even simplify refueling.

Lead? A few centimeters of collapsed matter would do a much better job. Lead is so 21st century!

Depends on TL but collapsed matter is advanced material technology.

You'd have to calculate the operational time of your chemical power plant using a single D-ton of fuel. If it was of any size it would be a very short duration.

A 1 d-ton Chemical power plant fuel tank I think would operate for approximately 33.6 hours producing maximum power output.

The rate Traveller power plants consume fuel, the milk carton of hydrogen wouldn't last very long.

I do not have a milk carton handy to extrapolate/interpolate how much in fractional d-tons could be stored, but I feel the duration would be very short also.
 
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