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Old 09-13-2018, 11:23 PM   #51
ak_aramis
 
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Default Re: Collapsibles and Drop Tanks

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Originally Posted by ak_aramis View Post
The prior canon is that jump fuel is used in under 20 minutes, and is spent whether or not the jump happens; you don't have time to drain empty and eject, as you finish using it as you enter jumpspace.

I don't have time at the moment to dig the T5 answer out accurately, but...

IIRC, the JDrive is actually an overdrive on the PP, coupled to the astrogation and initiator; the fuel has to be fed steady rate, and once started, there's no delay.
The T5.10 answer... (and the T5.09 one, as well)
The triggering of the drive, the burning of the fuel, and the entrance (or failure to enter) are all in the same, single step; there's no provision for cancellation, and all of the skill rolls are made BEFORE this step, save the engineering one.

The fuel is used to power the jump drive. Only 3 power plants can power a jump drive: Fusion, Antimatter, and Exotic Particle Collectors.
Fusion uses the standard hydrogen fuel. AM uses AM slugs. Collectors directly collect the needed exotic particles that the others use massive power to generate... taking a week to do so.
Any one of them, once you trigger the fuel, it's all used immediately to generate the singular power pulse.

Given that "any interference" results in an automatic misjump and/or failure... once you trigger, I suspect you cannot voluntarily abort, but that's not explicit (it's pretty strongly implied, however.)

Neither T5.09 nor T5.10-Draft tell how long the fuel takes to burn. I've sent this issue to Marc for his consideration.
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Old 11-27-2018, 06:51 AM   #52
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Default Re: Collapsibles and Drop Tanks

Zero velocity, in reference to what?
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Old 11-27-2018, 09:00 AM   #53
hal
 
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Default Re: Collapsibles and Drop Tanks

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Zero velocity, in reference to what?
Table Top ship movement...

;)

See the problem is - if you have zero movement relative to the star system the ship is within, gravity of the star will cause the ship to begin to fall "inwards" towards the start itself.

But if you're at zero movement relative to the star your at - then what of the relative movement of the star that you're jumping to?

If you're at zero movement relative to the entire universe - then you won't be at zero movement relative to any of the stars that are moving within the universe.

So the correct answer truly is, despite my answer being meant as a "teasing joke" - relative to all motion on the table top that you're moving the ship counter on.

Frankly, I've had to ignore some of the stuff being put out today for Traveller rules simply because they largely make the whole thing worse (In my opinion) than they do make it better. I've even gone the route of asking "does time pass one for one in jump space as it does in normal space". Why? Because if people in jump space experience 604,800 seconds while the universe also experiences 604,800 seconds (1 week in jump space), then why is it, that if a ship takes 10% less time in jump space, that the planets themselves haven't moved 10% less than what the astrogator originally plotted for when he plotted his jump? Ditto with if the jump takes 10% longer, why isn't his ship at least 60,480 seconds distant from the planet that he was trying to aim for, or the star that he was trying to aim for?

If a star is moving say, 135 miles per second - a miss by 60,480 seconds results in being off target by 8.165 million miles (let alone how much you missed a specific planet due to its internal orbital speed relative to the sun it orbits).

So - it is a can of worms that can be difficult to deal with - one that I've tried so that I could write a VB.NET program that would handle much of the issues involved.

Step 1: Establish a frame from which to establish relativity (ie relative to what).

Step 2: Establish a direction value that is the same no matter what. If it always points to the so called "Center of the universe" when mapping, you can always say that Galactic Center is to the Universe, what the North Pole is to mapping.

If everything rotates around something as a result of gravity, and the math involved works whether that source of gravity is a planet with its moons, a star with its planets - then might not the same hold true of stars around the center of its galaxy? Makes you wonder what the gravitational mass has to be at the center of the Galaxy to keep in thrall, so many star systems. It also makes you realize, that the further from the center of the Galaxy, the slower the stars can go relative to the center of the universe, but the faster the star systems have to be closer they are to the center of the galaxy. That alone means that matching velocities when you're in one star system to that of another star system can be brutal when talking of speed in excess of 100 miles per second overall (and yes, I googled the speed of our sun in our galaxy, which tend to all be in excess of 100 miles per second based upon how long it takes to complete one full revolution within the galaxy we inhabit.

Now, if the Jump drive automatically has the ability to compensate for the disparate velocities involved between two star system (by imparting extra velocity to the ship or bleeding off extra velocity as it enters into the second system from the first) - then we'd not have to worry about it.

In the end? The simplest answer to your question is "relative to the frame of the table upon which the game is played"...

;)
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Old 11-27-2018, 12:38 PM   #54
Fred Brackin
 
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T

In the end? The simplest answer to your question is "relative to the frame of the table upon which the game is played"...

;)
Einsteinians please note:Why Yes! this does mean that the table top in question is a privileged frame of reference! It's also why the Traveller galaxy is flat. :)
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Old 11-27-2018, 01:07 PM   #55
hal
 
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Default Re: Collapsibles and Drop Tanks

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Einsteinians please note:Why Yes! this does mean that the table top in question is a privileged frame of reference! It's also why the Traveller galaxy is flat. :)
*snickering like crazy here*
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Old 11-28-2018, 10:20 AM   #56
SteveS
 
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Default Re: Collapsibles and Drop Tanks

I would rule that getting a ship's velocity to something between the departure world's velocity and the destination world's velocity, both in the galaxy's frame of reference, is a standard part of astrogation.
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Old 11-28-2018, 02:50 PM   #57
hal
 
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I would rule that getting a ship's velocity to something between the departure world's velocity and the destination world's velocity, both in the galaxy's frame of reference, is a standard part of astrogation.
care to expand on that statement in another thread? *teasing grin*

I'm not certain if you meant it simplistically, as an acknowledgement of what I pointed out regarding different stars have different velocities where the velocity of a star can be measured in the vicinity of 100 miles per second etc.

If the Galaxy is a frame of reference, is there a singular frame of reference that all other Galaxies refer to as their point of origin or their point of orbit?

Proponents of the Big Bang theory suggest that there was a single point of origin, where the big bang originated and all matter etc - is expanding away from that point. Problem is - according to some observations, it appears that rather than moving at a constant pace away from us, certain galaxies are actually accelerating away from us. Be as that may be - this is all stuff that was not dreamed of when Traveller was First invented/created.

In the end? Moons orbit planets. Planets orbit Stars. Stars orbit something - a gravitational source at the center of a galaxy. If galaxies rotate around a common center, then it would seem that THAT location would be the ultimate point of reference. If galaxies do not rotate around a single point of reference, then it may be there is no single point of reference that all locations can be based off of.

Sooooo


Expand your statement?

:)
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Old 11-29-2018, 07:21 PM   #58
malloyd
 
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Default Re: Collapsibles and Drop Tanks

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Einsteinians please note:Why Yes! this does mean that the table top in question is a privileged frame of reference! It's also why the Traveller galaxy is flat. :)
Nonsense. It's clear that in the Traveller universe the stars and planets are all rigidly pinned to the plane that defines the galaxy and don't move relative to each other in the first place.

Honestly, there's a fair amount of stuff in pretty much any SF game or film that makes more sense if you assume that. In Traveller starting with the rules for interplanetary travel times that totally ignore the motions of the planets - admittedly a somewhat justifiable approximation given that ridiculous accelerations Traveller Maneuver Drives are able to generate, but still.
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Old 12-03-2018, 03:21 PM   #59
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Default Re: Collapsibles and Drop Tanks

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Zero velocity, in reference to what?
Per the fluff, relative to the target world.

T5 notes that the relative vector can be adjusted by non-gravitic thrusters while in jump, but gravitic thrusters don't work in jumpspace.
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Old 12-03-2018, 03:32 PM   #60
hal
 
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Default Re: Collapsibles and Drop Tanks

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Nonsense. It's clear that in the Traveller universe the stars and planets are all rigidly pinned to the plane that defines the galaxy and don't move relative to each other in the first place.

Honestly, there's a fair amount of stuff in pretty much any SF game or film that makes more sense if you assume that. In Traveller starting with the rules for interplanetary travel times that totally ignore the motions of the planets - admittedly a somewhat justifiable approximation given that ridiculous accelerations Traveller Maneuver Drives are able to generate, but still.
Ok - tongue in cheek time over...

If you had to pick THE best game that best handled reasonably decent planetary motion and acceleration rules etc - what would it be?

Just curious.
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