Here's another take:

I always imagine a ship travelling through J-space as being in a bubble that protects it from a space that is very different from realspace (and likely very bad for realspace ships and sophonts). I imagine the field ideally keeps any of the stuff of J-space contacting the stuff of realspace - much like Trek's 'matter/antimatter' separation.

To that end, I imagine the lanthanum grid being the field generator for the bubble. If the grid is damaged, small amounts of damage are likely no fuss - there's enough edge effects around small breaches to not let the field get penetrated. If the grid has some major damage, you might get some intrusion of J-space into the ship's damaged area and, given the perverse nature of J-space, you could have people nearby having nightmares/visions, you could have damage to the ship's systems or structure, you could have all sorts of creepifying effects.

That assumes an ongoing source of power to the grid. If you ever completely lost power, the entire grid would cease to generate the bubble and the entire ship would be engulfed with J-space and ... that would be VERY bad. I'd expect most of the time, that scenario means loss of ship and crew. In odd cases, I might be tempted to have it create something stuck between both spaces, echoing back and forth for short times (aka "Flying Dutchman").

Because the grid generates a field, there is no need (in my view) for the field to be 'supported' by hydrogen.

That said, the field takes a modest bit of ongoing energy to maintain and that produces a fair bit of heat. So The hydrogen is pumped out of the ship as coolant to keep the inside cool. That means as the ship travels, heating occurs (as the field contains the hydrogen) to the outside.

So when a ship emerging from jump:
a) The ship could have a brief flash if the fuel ignites (sort of like a flaming Sambucca)
b) The ship's thermal signature is significantly higher than normal (helps to prevent people sneaking up on planets unaware if they have thermal scanning...)

Could a ship contain its heat? Sure, there's some ways for a short period of time. You could avoid the 'flash' or the warm signature if you could contain the heat until you could duck behind a planet or something and blow your heat off after emergence sometime. 

Ahead of time, you could also have frozen some Hydrogen in tanks and let the heat from the heating from the generation of the jump bubble gradually melt this hydrogen (or you could install some other sort of frozen coolant) and thus you might not have to dump heat on exit....

This theory also explains the loss of some ships that may well have a very long time in J-space as their J-space mishap..... they overheat and cook from the outside (too much hot coolant to deal with) or the ship gets hotter inside until the systems feeding the hull grid malfunction... in either case, long periods of hanging out in J-space are a lethal event.... (not just +10%... I'm talking about multiple weeks or months).

Lots of ways to envision a J-drive. (Non-canonical of course)



On Fri, Jun 26, 2020 at 4:10 PM Greg Nokes <xxxxxx@nokes.name> wrote:
I have always been in the “you need a bubble if Stuff(tm) to keep the nasty jump space out” coupled with “The JDrive needs to keep the grid charged or Bad Things(tm) happen". Early experimentation showed that pure Hydrogen (being very simple Stuff(tm)) did not have strange interactions with jump space. The more impurities the higher chance of Bad Things(tm) happening.

The jump initiation flow is:

Navigator plots initial jump vector
Engineer uses small amount of fuel to charge Jump Field using Jump Drive or external PP (or black globe with out the fuel)
Navigator runs final plots
Engineer charges the Jump Field
Navigator hits the button
Engineer puts Jump Drive into “idle” keeping a trickle of energy into the field, and a flow of Hydrogen into the bubble.
Some time later, you pop back into real space.

Black Globes or external PP’s can provide the initial charge - but you still need the fuel for the bubble and for the field maintenance. Possibly less fuel, but still most of it. 

Is it cannon? Mostly, I guess ;D
It is realistic? ¯\_(ツ)_/¯ 






On Jun 26, 2020, at 12:22 PM, xxxxxx@gmail.com wrote:

This is my question too.

If the fuel is simply to run the ship for a week (give or take), then a much smaller amount of fuel is required.
If the fuel is the jump fuel, do the capacitors only need enough to run the basics of the ship for a week? Or ... what is that energy doing if the fuel powers the jump?

It's not that I want to argue about what Marc might have had in mind at the time, I just don't understand.

If the capacitors have to be charged with power from a plant or from weapons fire into the black globe AND you also need the fuel, is that what is supposed to be the normal case?

Just fuzzy stuff wherever you look.

On Fri, Jun 26, 2020 at 12:06 PM Phil Pugliese - philpugliese at yahoo.com (via tml list) <xxxxxx@simplelists.com> wrote:
On Thursday, June 25, 2020, 07:03:05 PM MST, Thomas RUX <xxxxxx@comcast.net> wrote:


Hello again Phil,
On 06/25/2020 6:33 PM Phil Pugliese - philpugliese at yahoo.com <xxxxxx@simplelists.com> wrote:

On Thursday, June 25, 2020, 01:16:51 PM MST, Thomas RUX <xxxxxx@comcast.net> wrote:

Hello Kelly,

> On 06/24/2020 8:21 PM Kelly St. Clair < xxxxxx@efn.org> wrote:
>
> 
> On 6/24/2020 7:36 PM, Rupert Boleyn wrote:
>
> > Gah. What a mess.
>
> Yyyyup.
>
> My take on that is that someone thought that a ship with a black globe
> being able to soak up hits and then jump out with that stored energy was
> Cool(tm), and then someone(s) else looked at that and realized it opened
> the door for "battle rider"-style starships being charged up by
> tanker-tenders rigged to fast-disconnect their cables while one or both
> move to minimum-safe-distance.

In MT "If a ship absorbs enough energy to make a jump and is supplied with sufficient fuel, it may jump at the end of the turn."

The battle rider would have to have fuel to make the jump.

Using the CT Annic Nova's jump drive you can probably put jump drives on battle riders. One negative is that once in system the battle rider is not capable of charging the jump drive to leave if things go south. Another negative is that the space devoted to the jump drive takes away weapons and armor.

Tom Rux
--------------------------------------------------------------------------------------

But exactly what does 'sufficient fuel' mean?
If it means the normal amount of fuel required to make a jump then nothing is gained from the external 'charging'.
Or does it mean enough fuel to provide a weeks worth of power to the ship while it transits thru j-space?
My interpretation is that when the diverted energy from a black globe has charged the capacitors and there is the correct amount of fuel, (sufficient fuel) for the selected jump the ship can make the jump. The only question I've had is has the navigator/astrogator plotted a jump destination and is the ship outside the 100D limit?


Tom Rux

----------------------------------------------------------------------------

But, but, that really doesn't make any sense as, if the ship had enough fuel to jump already that means that black globe charging of the capacitors is irrelevant, doesn't it?
If the ship already had enough fuel to jump what difference does it make if the capacitors were or were not charged at all? Or even partially charged?
I guess I don't see why all that fuel has to be present if the capacitors are fully charged. 
After all, in the usual routine operation, when the capacitors are fully charged, all the fuel is essentially gone, isn't it?

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