Travelling Across the Great Rift

I am not a Classic Traveller LBB purist but I do still like the idea that there are both basically modular starships that can be assembled relatively quickly and somewhat more cheaply from parts on a very large shelf and money and time no object bespoke starships.

Anyway having now actually looked at the 2 x Jump-4 scoutship that sort of initiated this discussion my fundamental problem with it is that it is a legal design thanks to MGT2 HG's reduced fuel option which chips away significantly at what I see as a key feature of the Traveller universe - Jump fuel as a rigid percentage of the ships tonnage.

Also so much for 'Great Rifts' when the smallest possible starship can cross 8 parsecs in two weeks...
 
a legal design thanks to MGT2 HG's reduced fuel option which chips away significantly at what I see as a key feature of the Traveller universe
Though legal and technically functional it looks to me like a rich mans toy. A one of just so the "adventurer" can say "I did it". Other than that it is useless. If anything it demonstrates how Jump beyond 6 is useless. ~47 MCr no passengers and 1 ton of cargo not exactly game unbalancing. Maybe an escape craft for a villain/dictator.
 
Anyway having now actually looked at the 2 x Jump-4 scoutship that sort of initiated this discussion my fundamental problem with it is that it is a legal design thanks to MGT2 HG's reduced fuel option which chips away significantly at what I see as a key feature of the Traveller universe - Jump fuel as a rigid percentage of the ships tonnage.

Also so much for 'Great Rifts' when the smallest possible starship can cross 8 parsecs in two weeks...
It isn't a legal design, the author has not applied fuel reduction correctly.
 
I put the Riftbreaker design into @Arkathan's spreadsheet.

The fuel, as previously stated, isn't correct. Using 1 J4 and 1 J2 with 12 weeks of operations took 5 tons less fuel than the designer calculated. In addition, cabin space isn't qualified as crew housing for longer term. Once again, we have someone who either didn't check the rules or their work. It also comes out to 101 tons as done by the design they published, so math is hard.

I corrected the fuel storage and changed the crew area to two double occupancy middle staterooms (because the original design had crew spaces for three). I had to chop 1/2 ton of cargo space, though that could be more than recovered if one of the cabins and one ton of common space came back out.

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I can get it to 1 J4 and 1 J3, but no better. Sadly, Mongoose has once again served up a broken design that doesn't follow their own rules.

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Yeah, you really have to stuff them in barracks and undercut their common area in order to get it to work.
Unless they REALLY like being intimate together, after two weeks, you might run into a Highlander trope...
There can be only one!
 
Yeah, you really have to stuff them in barracks and undercut their common area in order to get it to work.
Unless they REALLY like being intimate together, after two weeks, you might run into a Highlander trope...
There can be only one!
There should be a rule that there has to be common area equal to the crew count rather than the stateroom count. Or even 1 ton per single stateroom and 3 per double. ;)
 
3 per double doesn't seem to scale for crew, since it isn't an issue if they are used to it, but something along those lines, and tied morale. Amount and quality of the common area.
 
3 per double doesn't seem to scale for crew, since it isn't an issue if they are used to it, but something along those lines, and tied morale. Amount and quality of the common area.
I figure that long term cohabitation would require more space than normal to keep them from murdering one another.
 
Thought the fuel calculation looked dodgy.

Also begs the question of why not just keep the standard J2 drive and use fuel/cargo compartments that would let you do the 7 parsecs in 4 rather than 2 weeks but at half the cost of the ship.

As for the cabin fever problem that is what medical slow drug is for.
 
Last time I calculated out a rift cruiser, assuming appropriate infrastructure at either end, the sweet spot was a jump drive factor/three.

Include drop tanks, and sixty percent jump fuel tanks.

You won't need Nostradamus as your astrogator.
 
3 per double doesn't seem to scale for crew, since it isn't an issue if they are used to it, but something along those lines, and tied morale. Amount and quality of the common area.
My back-of-the-envelope musings seem to settle in at 2.5 tons per person between cabin and common space for professional crews in the current rules. The tentative break seems to be 1.5 tons for 'daily space' plus 1 ton for living/sleeping, mix-and-match for degrees of privacy. 1.25 tons seems to be the common threshold for cramped living, while 0.5 seems to be a minimum for stand-up/lie-down space.

Double standard staterooms provide 2 tons personal space, and the recommended common area is an additional 0.5 tons per person.
Cabin space (for short term durations) is 1.5 tons per person. while an additional 0.375 tons of common space is suggested, cabins are intended for short durations and a counter-argument they are intended for "stay here, don't wander" use is also available. The 1.5 tons is not comfortable living space, but enough for short-duration trips measured in hours.

Notably cramped accommodations:
Barracks permit 1 personal ton, and recommended common area is 0.25 tons.
SOL Blocks (per Arkathan's file, I don't have this book (yet)) provide 1 ton of personal space and recommend .25 tons of common area

Restricted movement:
Brigs at standard occupancy technically provide 2/3 of a ton per person, but if we stretch the description so that 1 of the 4 tons per 6 person block is needed for the security apparatus, we can adjust to a familiar 0.5 ton per person. As brigs are intended for containment, and any crew or 'standard' guests will already have space calculated for, there is no additional common area.
 
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