Deep Space Jumps

A thread of 3 messages, 11 May 1994 to 12 May 1994, in the order they were sent.

#7530 Deep Space Jumps

 [email removed] writes:

 > There is nothing in GDW's current (or past) Traveller series technology
that
 > requires a celestial body for jump.

 and Gerald S Williams <[email removed]|> replied:

> Except the background, that is.  Many of the supposed barriers
> to travel would not exist without this as at least a practical
> requirement (for example, you can do it, but you waste fuel and
> it adds an element of danger).

{specific examples deleted}

The major problem as I see it is the loss of cargo space where you
have to carry the extra fuel.  Any of these deep space refueling
stations would be expensive to operate.  I would guess that a
constant stream of tankers would be necessary to support a busy
deep space station.

The few imperial ships that are meant to function by using a deep
space stopover, usually carry a fuel bladder in their cargo hold,
or would have the extra fuel capacity built in.  The Imperiallines
Type TJ Frontier Transport is a ship that comes to mind with it's
jump 6 capability as opposed to the Type TI Frontier Transport
with its J-2 capablility.  The TJ is meant as a special courier
and is designed as such. The TJ even looks like the TI for
security reasons.

The one problem I have is with the TNE ship designs.  Now that we
are back to somewhat realistic thrusters, I find that I need more
fuel for my M-drives than for the J-drive.  So if you are willing
to sacrifice maneuverablity when you exit from jump, most TNE ship
already have the capability to do a deep space stopover without
carrying extra fuel.

CT and MT ships however would need to carry extra fuel.  I agree
that a deep space stopover is allowable, however it should be a
MAJOR problem to do so.  Either the refueling problem, difficult
piloting (or rather navigation) task, or something.  It is
allowable as it is the way the Aslan bridged the Riftspan Reach
gap (commercial ships are still only J-2 or J-3).  See GDW Alien
Module 1 for details.

I disagree that it creates a big problem with the Virus and the
Regency blockade.  The Virus doesn't have the refueling capability
to move a large fleet by the way of a deep space stop, and knowing
that the regency is watching for them, they wouldn't put
themselves at such a tactical disadvantage. (Less than 20 G-turns
of fuel remaining as opposed to the 40+ G-turns fully fueled)

It makes even less sense for merchantmen to use smaller J-drives
as this increases the travel time and decreases the profit.

One last point, In Arrival Vengence the ship rendevous with a deep
space comet for refueling on the way back to the regency.  This
allowed them to cross the Great Rift through the Gushemege,
Corridor, and Deneb sectors.  But the location and orbit of the
comet was a state secret for such an emergency.

John Bucsek
[email removed]

#7540 Deep Space Jumps

[email removed] (David Johnson) says:

>I've always considered that jump calculations use gravity wells as
>`targets'.

I think that instead it's calculations based on charted positions,
etc.  While your idea is interesting, how do you locate the
targets?  Also, this seems to be against the 100 diameter idea: you
want to be far away from gravity wells, not close to them.

I think that you target your ship towards a coordinate in space,
not towards a gravity well...

If I were a player in your campaign, I would want to know how my ship
is targeting gravity wells parsecs away: that would indicate alot of
interesting possiblities ;-)

Matt

#7548 Re: Deep Space Jumps

John Bucsek writes:

> The major problem as I see it is the loss of cargo space where you
> have to carry the extra fuel.

Perhaps it is no longer true, but it used to be that you GAINED
cargo space by doing a number of smaller jumps (the fuel usage
can be recalculated based on a smaller ship's mass--if you base
fuel usage solely on hull size, use inflatable or drop tanks).
In addition, you saved space by using a smaller jump drive.

> I disagree that it creates a big problem with the Virus and the
> Regency blockade.  The Virus doesn't have the refueling capability
> to move a large fleet by the way of a deep space stop, [ ... ]

Without TNE, I am at a disadvantage.  It occurs to me that a
large fleet action would not be necessary, though.  Why not
penetrate to the center of the Regency where they are not so
vigilant and "infect" them from the inside out?

> It makes even less sense for merchantmen to use smaller J-drives
> as this increases the travel time and decreases the profit.

This is a reasonable argument, although I believe that most
merchants will not have large jump drives.  They are far too
expensive, and less of your ship is dedicated to cargo.  They
will likely restrict their trade to nearer stars, except in
special cases, which would justify either the extra expense
or the extra time.

Again, things may have changed, but it used to be that a
large jump drive (and equipment to support it) overwhelmed
the cost of a ship, to the point where it was generally not
profitable to use one in a trader.

> CT and MT ships however would need to carry extra fuel.  I agree
> that a deep space stopover is allowable, however it should be a
> MAJOR problem to do so.  [ ... ]

> One last point, In Arrival Vengence the ship rendevous with a deep
> space comet for refueling on the way back to the regency.  [ ... ]

and David Johnson writes:

> I've always considered that jump calculations use gravity wells as
> `targets'. [ ... ]

I think we are all in agreement.  The background states that jumps
to deep space are possible, but indirectly implies that they must
not be easy.  We already know gravity affects jumps, why not use it
as a 'target' as David Johnson suggests (perhaps even a mandatory
one)?  This is consistent with the Arrival Vengeance using a comet
(it has it's own gravity well, even though it is small).  Perhaps
sufficiently dense "dark matter" could even be used, but precisely
locating it might be difficult.

,-----------------.
|Gerald S Williams|
|[email removed]|
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