Reduced Fuel consumption by Tech Level

[BrianSmaller]

Just a question chaps. Forgot the Universal constant, C and all that crap. The real constant in the Traveller universe is that at any tech level from the introduction of Jump Drives right up to maximum Imperial, drives still use the same amount of fuel. 10% per Jump right? So has anyone done any work on a reducing fuel volume by Tech level chart or some such thing? I mean apart from being a bit smaller, a TL15 Jump1 drive still gets the same mileage as a TL10 Jump 1 drive.

[ShawnDriscoll]

10% per Jump right?

That's the fuel usage you're aiming for?

Anyway, did you look at this rule yet? http://www.freelancetraveller.com/featu ... eakjd.html

[BrianSmaller]

10% per Jump right?

That's the fuel usage you're aiming for?

Anyway, did you look at this rule yet? http://www.freelancetraveller.com/featu ... eakjd.html

Sorry - I meant 10% of ships mass per jump number was what it is now - so somewhere between 10-60% of the ship. I just cannot see the advantage of plonking a tech level 15 J-drive into a ship when apart from J6 the older tech ones do the same job at the same fuel consumption. The difference in j-drive engine size is not all that great - it is the fuel.

Anyways - off to read that link you posted Shawn - many thanks.

[Condottiere]

Depends on how hydrogen interacts in the transition process, and why you need so much of it.

Tech level fifteen jump drives with lower capabilities could be a little bit cheaper.

[simonh]

I just cannot see the advantage of plonking a tech level 15 J-drive into a ship when apart from J6 the older tech ones do the same job at the same fuel consumption.

It's the 'apart from J6' bit that's the kicker. For some applications, that an extremely valuable capability.

It might help to understand why you want to change the way this works. In what way do you want to change the setting? How would making higher tech ships even more capable and performant than they are now enable you to do with the game that you can't do now? What effect are you aiming for?

Simon Hibbs

[Reynard]

Ever think the fuel consumptions for Jump and Power Plants have already factored in tech related efficiencies and they just happen to hit those particular formulas otherwise fuel consumption would be higher? Next step to fuel efficiency is tech 17+ anti-matter fuel.

[atpollard]

High Guard presents differences between the TL 9 Jump-1 drive and the TL 15 Jump 1 drive.
IIRC, they get smaller and more expensive for a few TLs and the drop in cost at each higher TL ... [going to look it up] ...

... [Here it is: High Guard, p.52-53]

So from the Core Rulebook, J-Drive A is 10 dTons and MCr 10.
From High Guard, that would be TL 9 for a Standard J1 capable J-Drive A (10 dTons, MCr 10).
From High Guard, I could "improve" that up to a TL 12 J1 capable J-Drive A (7.5 dTons, MCr 20).

High Guard (pg 52) also states:

There is a 5% price discount per TL for older technology devices if bought new at the source, to a maximum of –30%.

Therefore, from High Guard, I could purchase a TL 12 version J1 capable J-Drive A manufactured at TL 15 at a 15% discount (7.5 dTons, MCr 17) or a TL 9 version J1 capable J-Drive A manufactured at TL 15 at a 30% discount (10 dTons, MCr 7).

It has been suggested that the "JD Fuel" is not fuel in the traditional sense, since the energy released by fusing tons of hydrogen is staggering and would melt the ship at anything below 100% efficiency, so a bubble of hydrogen around the ship to insulate it from Jump Space is a common technobable explanation. If this is the case, then jump fuel is more like displacement in a wet navy ship ... a 100 displacement ton wooden ship in 1800, displaces exactly the same volume of water as a 100 displacement ton racing boat in 2015. Displacement does not change with TL, and neither does the Jump Bubble. [shrug ... at least that's the common argument].

If you want to change JD fuel volume, I suggest really shaking things up and swapping MD Fuel for JD Fuel.
JD Fuel = 1% per Jump Number (to power a JD)
MD Fuel = 10% per Gee (reaction Mass for a fusion torch)
It is still all handwave magic technology, but it is a step closer to reality.

[Rikki Tikki Traveller]

Since the very first days of using the Traveller rules back in 1977 (yes, I am that old), I have had a house rule that reduced Jump fuel costs with TL.

I dropped it 1% per TL. Yes, that makes TL15 ships VERY spacious compared to their TL9 counterparts but that was the point wasn't it. Why would anyone spend more credits to save a couple of tons in drive size? FUEL that is what.

I also used a House Rule that had an additive to fuel (creatively called Tylium after BSG) that cut fuel usage in half. So you had Unrefined Fuel, Refined Fuel and Enriched Fuel. Enriched Fuel.

[Condottiere]

You could make it:

Tech level manufactured-9(0.1%)(jump)

[F33D]

Just a question chaps. Forgot the Universal constant, C and all that crap. The real constant in the Traveller universe is that at any tech level from the introduction of Jump Drives right up to maximum Imperial, drives still use the same amount of fuel.

"Fuel" is a bit of a misnomer for this in MGT. The H2 used by the J-dive is not used as fuel. It is used to form a bubble outside the ship. This bubble is needed to enter, remain and be protected from jump space. The further you travel the larger the bubble needed. So, no matter the TL of the drive, it is Jump space itself that sets the amount needed...

As much of MGT was derived from early T5, that rule set may go into more detail.

[Subzero001]

what about ship parts bought outside of the imperium for instance the zhodani or darians? etc...

like j drives and m drives with this incorporated in to them: from the psion book pg 68

DRIVE AUGMENTATION
This power enables a psion to augment the capabilities of a conventional J or M drive. He does not fold space but provides psionic power to increase the ship’s speed whilst the conventional drives are used, resulting in reduced fuel usage. Every 2 Psi points used to augment an operating drive increases the ship’s jump range by 1 or its Thrust by 1. Every 200 tons of hull displacement imposes a –1 DM to the Ship Integration roll, which must be made to successfully augment the drive in use. When used with a Jump drive, the amount of time spent in jump space is not decreased by the Effect of the roll; only the range is influenced. The same DMs as those used for Fold Space are applied when augmenting a drive.

Ship Integration, Psionic Strength, 10-60 minutes, Average (+0).Costs: 2 per Jump or Thrust 1 equivalent.

from my understanding all beings have a little psion energy in them so a small hidden storage device that taps the passengers / crew on ship to provide the necessary energy reserve shouldn't be an issue or really noticed by the "normal" beings.

this would fall under your "Reduced Fuel consumption by Tech Level" idea

[Condottiere]

Some passengers in a Zhodani low berth might be permanent residents.