Fuel and jumping

[Sigtrygg]

Basically, you have to tinker around with an imperfect formula to balance out the factors of mobility, protection, and firepower, as it should be; fuel bunkerage would have to even out between jump drive and rocket consumption.

I haven't read Marc Miller's article, and I suspect that however Mongoose Two's variant of jumpspace works, it veers off from his vision.

There's the forthcoming Starship Operator's Manual that may clear things up, or obfuscate them further.

I posted the relevant bits a few posts upthread - you didn't bother to read them?
The two articles are almost word for word the same - the JTAS 24 and MgT JTAS 2 Jumpspace article.

I really hope the authors of MgT SoM do their research and consider implications a bit better than whoever wrote the rule in the core book that is contradicted by High Guard and Great Rift.

 

[Seffix]

How do folks think this works with Deeps (The Great Rift Bk 1, p.20), where more fuel is required during jumps or the field collapses?

My take would be to have the engineer woken by weird noises or smells from the J-Drive and realize what is happening (these are known, albeit not understood, phenomena), so she staggers back to Engineering and starts bleeding fuel into the system for a stabilizing burn, which she has to do every few hours till they exit the jump.

 

[Sigtrygg]

What are these heretical tomes you speak of?
It was 10% in the seventies. It is 10% now. Those others made my group not play Traveller, unless we used the LBBs... From the Seventies...
With FASA ship deck plans...

I still mostly play CT, I used to cherry pick rules from other editions but now it is almost 77 with a couple of cherries
[the 81 drive table, pulse laser -1 to hit and 2 damage rolls, crew hit inflicts 4D hits on a random crew member. T4 damage resolution although MgT is pretty similar]
The MgT boon/bane system and a lot of their adventure books, Great Rift, DNR, SotA, CSC, Vehicles, Robots

 

[Spartan159]

I've been toying with the idea of using 7% instead of 10%. Not real sure on the impact yet. Would make high end drives actual viable though. Strictly an IMTU project. I also happen to be one of those power the jump drive via burning hydrogen or direct energy from a collector or black globe people, and use either a grid, plates or jump bubble to keep out those nasty jump spaces. Not hydrogen surrounding the ship.

 

[Vormaerin]

The short answer is that the rules for jumpspace don't make sense and are not consistent. Often getting retconned within the same edition, much less between editions. Classic Traveller (70s), Classic Traveller (80s), MegaTraveller, Traveller: New Ear, Gurps Traveller, T20, HERO Traveller, T4, T5, and Mongoose Traveller all have slightly different versions.

So you can pretty much use any fluff you want at your table, because no one but you and your friends will care. The only things that need to be true to maintain the integrity of the setting are:

1) The Jump Drive does *something* to move the ship through jump space a number of parsecs in a designated amount of time
2) Ships in jump space experience time at the same rate as those not in jump space but are out of contact with real space
3) The most efficient catalyst for whatever Jump drives do known to current technology is large quantities of liquid hydrogen.
4) Jump drives can't be "charged up" and hold that charge any significant length of time.

Why liquid hydrogen is the best and what it does is....unclear. The JTAS article reprinted in Mongoose JTAS is the earliest attempt to explain it.

Traveller has had, since the Classic Traveller (80s) era, 3 techs that severely complicate any attempt to provide a coherent explanation of jump drives.

The least problematic is the collectors of Annic Nova fame. These are alien ultra tech devices that indicate that other materials than liquid hydrogen can be used to make the jump drives work. It just requires future tech (TL 16+ according to T5 and MgT) to gather and use them.

The second, more problematic alien future tech, is the black globe generator. That allows you to dump the gathered energy to catalyze the jump drives. This is really tricky, because it suggests that the L-Hyd is basically just a store of energy for the drives. So you have to come up with reasons why really large volumes of L-Hydrogen is the most efficient store of energy for triggering jumpspace. And, unless you rule that capacitor discharge is mandatory instead of something you "can" do, you need a reason why you couldn't just charge these capacitors from the station before zipping out to the jump point. The black globe itself is like TL17, iirc, but there's no suggestion that it has special futuretech capacitors it dumps the energy into.

And the worst offender, imho, is the L-Hydrogen Drop Tanks. Because for this to make sense, you have to assume that all the L-Hydrogen is completely converted into energy to trigger the initial jump rather than being used over time during the jump. And that means jump drive limits are limits of volume, not mass. (because the mass of the L-Hydrogen in the Drop Tanks doesn't count towards the jump capacity, but the on board volume that used to hold the fuel in an internal tank still does).

 

[JustEastOfTheEdge]

I wonder what would happen if I had a ship with 2 separate jump drives, then I activate the 1st one to enter jumps space, and then activate the 2nd one ...

 

[Condottiere]

What is processed fuel?

Refined hydrogen, the Perrier of hydrogen.

What is unprocessed fuel?

Tap water.

Outside of astronavigation, and the Scottish engineer lamenting to the Captain, everything happens in six minutes, then shuts down.

My presumption is, based on Collectors, is that the hydrogen, or some of it, is transformed into exotic particles.

Whatever is within the jump bubble, could be a lucky byproduct, which doesn't have to be manufactured separately, which is where I assume the hydrogen comes from.

 

[Condottiere]

1. An operating jump drive requires several basic components which, when operating together, make jumping possible.

2. Jumping uses large amounts of energy to rip open the barriers between normal space and jump space. Normally, only a fusion power plant can supply this energy. Some alternate systems make use of solar power generators (which operate far more slowly) or anti-matter power systems (rare and very high-tech).

3. Currently, the jump drive draws from the available energy pool; the direct sunflower approach doesn't work, since you'd have to withddraw the solar panels before jumping.

4. Once power is generated, it must be stored until the instant of jump. Capacitors or large fast discharge batteries fit this requirement.

5. Obviously, written before we could use normal batteries; but to be fair, I think it's both storage and transformer.

6. The hull of a starship must not only be constructed to withstand normal space; it also must withstand the rigors of jump space.

7. Too vague: why can't I use wood or latex?

8. Starship hulls contain as an integral part of their structure a network of wiring which maintains the jump field around the ship. Without this field, the natural physics of jump space would intrude into the ship’s interior and the alien physical principles would make life impossible, operation of equipment unpredictable, and even the passage of time would be altered. Breaks in the protective network within a starship’s hull are a primary cause of the loss of ships when jumping.

9. And how does this work with a jump bubble?

 

[Condottiere]

A. The need for this network in a ship’s hull also indicates what happens to matter (personnel, small craft, missiles, etc) ejected from a ship while jumping, becoming subject to the physics of jump space. People die; equipment malfunctions; small craft disappear. Some attempts have been made to launch a starship into jump space from other starships; problems in properly matching drive fields, or even turning them on near other ships, has shown that the technique is impractical at best, and probably impossible.

B. Feels like it has to do with keeping in phase.

C. We could be ghosts in the jumpspace universe.

D. Jump drives have precise power requirements which can only be met if the power is fed under computer control. In addition, the calculations needed for a jump require a high level of accuracy.

E. With computers made in the Seventies.

F. Which I believe an iPhone can beat.

 

[Condottiere]

G. The jump coils that channel a ship’s energy within the jump drive are
constructed of lanthanum, a rare earth which has exactly the correct
properties for the purpose. Lanthanum coils are used to control the drive
energies during a jump.

H. Other materials have been used or substituted, but none function with enough reliability or efficiency to make them practical.

I. Let us know what these are, especially if we get cheaper jump drives.

J. When the jump drive is activated, a large store of fuel is fed through the ship’s power plant to create the energy necessary for the jump drive.

K. So, jump turbines.

 

[Condottiere]

L. In the interests of rapid energy generation, the power plant does not work at full efficiency, and some of the fuel is lost in carrying off fusion byproducts, and in cooling the system.

M. Pretty sure in Mongoose One you still needed a dedicated fusion reactor, inefficient but overclockable.

N. Presumably, one byproduct is the jump bubble.

O. So, hot hydrogen.

P. Or hot water, if you use unprocessed fuel.

 

[Condottiere]

Q. At the end of a very brief period (less than a few minutes), the jump drive capacitors have been charged to capacity.

R. Flushing the hydrogen, and charging the capacitors are two different, if related, actions.

S. Under computer control, the energy is then fed into appropriate sections of the jump drive and jump begins.

T. Well, it tells the jump drive precisely what to do, so there is a computational function within the jump drive.

U. Otherwise, it would be a pure transformational process.

 

[Condottiere]

V. The drive’s first function is to tear a hole in the fabric of space. The hole is precisely created and the ship naturally falls into the breach on a carefully directed vector.

W. Implies that you do go on a straight line, and can't really pick the vector you exit from.

X. The drive then directs some of its energy to sewing up that hole again. The act of closing the hole severs the ship’s ties with normal space and allows it to begin its jump.

Y. What happens when you don't?

Z. The jump aborts?

 

[Sigtrygg]

I wonder what would happen if I had a ship with 2 separate jump drives, then I activate the 1st one to enter jumps space, and then activate the 2nd one ...

There was a GDW JTAS article about these sorts of shenanigans - basicall the ship is never heard from again unless it is full of PCs and is part of the referee's adventure.

 

[Sigtrygg]

The short answer is that the rules for jumpspace don't make sense and are not consistent. Often getting retconned within the same edition, much less between editions. Classic Traveller (70s), Classic Traveller (80s), MegaTraveller, Traveller: New Ear, Gurps Traveller, T20, HERO Traveller, T4, T5, and Mongoose Traveller all have slightly different versions.

So you can pretty much use any fluff you want at your table, because no one but you and your friends will care. The only things that need to be true to maintain the integrity of the setting are:

1) The Jump Drive does *something* to move the ship through jump space a number of parsecs in a designated amount of time
2) Ships in jump space experience time at the same rate as those not in jump space but are out of contact with real space
3) The most efficient catalyst for whatever Jump drives do known to current technology is large quantities of liquid hydrogen.
4) Jump drives can't be "charged up" and hold that charge any significant length of time.

Why liquid hydrogen is the best and what it does is....unclear. The JTAS article reprinted in Mongoose JTAS is the earliest attempt to explain it.

Traveller has had, since the Classic Traveller (80s) era, 3 techs that severely complicate any attempt to provide a coherent explanation of jump drives.

The least problematic is the collectors of Annic Nova fame. These are alien ultra tech devices that indicate that other materials than liquid hydrogen can be used to make the jump drives work. It just requires future tech (TL 16+ according to T5 and MgT) to gather and use them.

The second, more problematic alien future tech, is the black globe generator. That allows you to dump the gathered energy to catalyze the jump drives. This is really tricky, because it suggests that the L-Hyd is basically just a store of energy for the drives. So you have to come up with reasons why really large volumes of L-Hydrogen is the most efficient store of energy for triggering jumpspace. And, unless you rule that capacitor discharge is mandatory instead of something you "can" do, you need a reason why you couldn't just charge these capacitors from the station before zipping out to the jump point. The black globe itself is like TL17, iirc, but there's no suggestion that it has special futuretech capacitors it dumps the energy into.

And the worst offender, imho, is the L-Hydrogen Drop Tanks. Because for this to make sense, you have to assume that all the L-Hydrogen is completely converted into energy to trigger the initial jump rather than being used over time during the jump. And that means jump drive limits are limits of volume, not mass. (because the mass of the L-Hydrogen in the Drop Tanks doesn't count towards the jump capacity, but the on board volume that used to hold the fuel in an internal tank still does).

Every version of Traveller has the jump drive volume based rather than mass based. MWM's article clearly states that lots of energy is generated and then fed into the capacitors. From that point on it is the jump engine and the energy in the capacitors that gain entry to jump space - which is why you can use a collector or an antimatter power plant.

The black globe generator for some reason can fill the jump capacitors but the ship still needs fuel to jump, my only explanation for this is that the fuel is needed as coolant.

The Annic Nova collector tech is TL14 - see T5 and MgT High Guard.

I claim a few credits for stuff that has appeared in print, and the one I wish I could revisit is when I "invented" "exotic jump particles" as an explanation for the collector being more than just a big PVC.

A particle is just an excitation in a quantum field, so really these exotic jump particles are an excitation of the jump field. Make the jump field tachyonic (a tachyonic field in QM is allowed, as is tachyonic condensation, but not FTL tachyon "particles")

Tachyon condensation is a process in particle physics in which a system can lower its energy by spontaneously producing particles. The end result is a "condensate" of particles that fills the volume of the system. Tachyon condensation is closely related to second-order phase transitions.
The appearance of tachyons is a potentially serious problem for any theory; examples of tachyonic fields amenable to condensation are all cases of spontaneous symmetry breaking. In condensed matter physics a notable example is ferromagnetism; in particle physics the best known example is the Higgs mechanism in the Standard Model that breaks the electroweak symmetry.

I would have the jump field tachyonic condensation a fourth order phase transition - that should be enough handwavium to cover it.

 

[JustEastOfTheEdge]

"handwavium".

Definitely something involving re-routing plasma conduits , that seems to fix everything and anything in Trek.

 

[AndrewW]

"handwavium".

Definitely something involving re-routing plasma conduits , that seems to fix everything and anything in Trek.

Don't forget the deflector dish.

 

[AnotherDilbert]

1) The Jump Drive does *something* to move the ship through jump space a number of parsecs in a designated amount of time
2) Ships in jump space experience time at the same rate as those not in jump space but are out of contact with real space
3) The most efficient catalyst for whatever Jump drives do known to current technology is large quantities of liquid hydrogen.
4) Jump drives can't be "charged up" and hold that charge any significant length of time.

Why liquid hydrogen is the best and what it does is....unclear. The JTAS article reprinted in Mongoose JTAS is the earliest attempt to explain it.

The jump drive just needs power, lots and lots of power, as per the JTAS#24 article.

Fusion using commonly available hydrogen is a simple solution.
Antimatter/matter recombination can also work, beyond 3I tech, but requires an industrial base to manufacture fuel.
Exotic "Collectors" collects energy somehow, and can deliver it to the jump drive.

 

[Condottiere]

About as much power as basic services, or the manoeuvre drive.

The interesting bit is, once I reflected on this, our jump drive actually can function on plain water.

And Miller Lite beer.

Risky, but doable.

 

[Subzero001]

If fuel power goes thought the "power plant" to provide power to charge up the jump compactors then why the requirement of needing fuel to be from internal tanks and not a external tank like a balloon being deflated to be burned in the "power plant"? this would make the ship better suited for cargo transport since you don't have to jump with empty dead space every time.