Double Jumping

[fredofmars]

Originally posted by Sir Dameon Toth:
This is an idea I came up with for my universe:

JUMP MULTIMPLEXOR DRIVE

<snip>
The cost is calculated similarly: Ship Tonnage x Jump Multimplexor x 20 (modify the .02 and the 20 in the calculations if you want to make this more rare in your campaign). Using the example above, 200 x 3 x 20 = Cr12,000. It takes 12 man-hours per ton to install properly.

Since ship costs are typically listed in megacredits, the above example of a JM would be MCr12,000 (12 billion credits). A JM for a 500,000 dton capitol ship that does jump-4 (the IN standard) would cost MCr40,000,000 (40 trillion credits). At least that's how it would be IMTU.

While MCr12,000 is possible for something the size of the Imperium to absorb a few of in its ship building activities, it would put it out of the range of PC purchase. If they wanted one, they would need to acquire it through extra-legal methods in all likelihood. It would also not be a major factor in a Trillion Credit Squadron battle IMTU, since it would eat up much of the budget to equip even a fairly small ship (a TCr1 budget would buy a JM for a ship of 12,500 dtons without anything left over to buy the actual ship).

If I used JMs IMTU I would have them be experimental at TL16 (thus being barely possible for the most extreme of the Imperial research stations to make a small number of "breadboard" JM-2 level machines). Once they became more readily available at TL17, the JM-2 level machines would drop in cost by perhaps a factor of 10. A JM-3 would be experimental at TL17 and more available at TL18, etc.

Like black globes, I would have JMs be a fortuitous find at an Ancient site, that the IN has been able to copy sufficiently well (at this extreme TL16 research station) to make a handful of JM-2s.

I would also apply the ship refitting times from TCS for putting a JM into an existing ship. The rules on p34 say that a major change (such as to the engines) takes a quarter as long as building a new ship. A B2 standard hull of 100 dtons takes 9 months to build, so a refit to accomodate a JM would take 2.25 months.

 

[Whipsnade]

Originally posted by RainOfSteel: Except that the exact exit point is not determined until exit.

Chris,

Not exactly correct.

The where of your jump exit point is known within 3000 km per parsec jumped. That's straight from Marc W. Miller himself. The trouble arises in not knowing what the when you'll arrive at that where. All that stuff around that where point moves during the 33.6 hour window your when can occur. That's the real problem.

Back to Horatius' questions:

- First; canonically you can not re-engage the jump drive during jump because the jump drive is working throughout jump. Destroy the jump drive while a ship is jump and you'll destroy the ship. Turn the jump drive 'off' while the ship is in jump so you can re-engage it and you'll destroy the ship.

- Second; as others have already posted, there are examples in canon of what you are suggesting. None worked and most ended in disaster.

- Third; the descriptions about and limitations of jump drive found in canon mean ABSOLUTELY NOTHING in Your Travller Universe unless you wish them to. If jump drives can re-engaged to create longer jumps IYTU then so be it. It certainly sounds like a lot of fun!


Have fun,
Bill

 

[JAFARR]

Warp Factor 5 Scotty! Oops wrong Si-Fi universe! From what I have been able to discover warp drives are the one area of starship technology where the Star Trek universe is more capable than the Traveller universe.

 

[parmasson]

I had imagined a jump as being like this . . . J-space diagram
The limit of J-space is not unlike our speed of light. It is a limit that cannot be passed because of natural laws. The ship is "sunk" into J-space and pops out like submarine or object thrust under the water at great speed some time later.
Each line on the graph represents one jump "level" deeper into J-space. IMO the vessel literally skips from one location to the next as if you were jumping through the air. You cannot push off again while in mid jump because you are already in transit and have nothing to push off from. What I mean is that if you were to launch yourself out of a playground swing into the air you could not re-launch until you hit the ground. Perhaps this is a bad analogy but I hide behind the fact that it is fiction.

Respectfully Submitted

 

[Chaos]

I can think of two other uses for having two Jump Drives in the same vessel...theoretically at least.

1. the ship is propelled through Jump Space twice as fast as with only one Jump Drive, so that a Jump only takes 3.5 days on average
2. the second Jump Drive can prematurely propel the ship from Jump Space to normal space, so that a Jump over less than maximum distance takes less than a week to complete.

 

[Flynn]

All of this was explored in an article called Project Farstar, from Challenge #33, IIRC. I'd highly recommend it, as it's a good read and presents a number of entertaining options based on the thought exercises pursued here.

Hope this helps,
Flynn