Fuel and jumping

Randal

Mongoose
Hello sophonts,

I am just checking as I have had this assumption since 1989 and I want to make sure I am correct. In Mongoose Traveller the fuel used when jumping is burned in a short space of time to generate the singularity (into which the ship also injects hydrogen).

It does not burn the fuel required for jump through the ship's 7-days in jump.

Am I correct?
I am writing something and it has occurred to me I have never questioned this assumption.

Thanks in advance.
RG
 
You will notice the jump also needs power during the entire journey as well as a separate boost of hydrogen for the jump entry and sustained bubble.
 
No hydrogen is needed to maintain a jump bubble, nor is hydrogen used to make the jump portal.

Very large amounts of power from the power plant are needed to make the portal, which involves a massive dump of fuel into the power plant. The jump field is maintained by the power plant and cables that crisscross the hull.

A collector uses no hydrogen.

MWM's article in MgT JTAS2 gives the procedure for the Traveller universe.

REQUIRED ITEMS
An operating jump drive requires several basic components which, when
operating together, make jumping possible.
Power Source
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).
Energy Storage Nodes
Once power is generated, it must be stored until the instant of jump.
Capacitors or large fast discharge batteries fit this requirement.

Strong Hull

The hull of a starship must not only be constructed to withstand normal
space; it also must withstand the rigors of jump space. 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.
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.
Computer
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.
Jump Coils
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. Other materials have been used or substituted, but
none function with enough reliability or efficiency to make them practical.

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. 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. At the end of a very brief period (less
than a few minutes), the jump drive capacitors have been charged to
capacity. Under computer control, the energy is then fed into appropriate

sections of the jump drive and jump begins.
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. 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.
 
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No hydrogen is needed to maintain a jump bubble, nor is hydrogen used to make the jump portal.
Well, my Core Rulebook(2016) says in the section for Spacecraft Operation in the paragraph Fuel and Jump Travel on page 148:

The singularity is driven out of our universe creating a tiny parallel universe which is then blown up like a balloon by injecting hydrogen into it.

I guess somehow they have to explain where the huge quantity of hydrogen needed for a jump goes all of a sudden. It would also explain why firing the jump drive takes 1D x 10minutes instead of seconds.
 
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Since the power plant fuel dump is inefficient, and is both cooling and carrying off fusion end product, you'd expect the pocket to be filled by a mix of hydrogen and helium.
 
Well, my Core Rulebook(2016) says in the section for Spacecraft Operation in the paragraph Fuel and Jump Travel on page 148:

The singularity is driven out of our universe creating a tiny parallel universe which is then blown up like a balloon by injecting hydrogen into it.

I guess somehow they have to explain where the huge quantity of hydrogen needed for a jump goes all of a sudden. It would also explain why firing the jump drive takes 1D x 10minutes instead of seconds.
The article I quoted is in a Mongoose Journal and Mongoose has collectors (big solar sail like canopies that do not require hydrogen) as options in High Guard - how can I put this nicely

the rulebook is wrong, it is contradicted by MWM and High Guard.
 
Since the power plant fuel dump is inefficient, and is both cooling and carrying off fusion end product, you'd expect the pocket to be filled by a mix of hydrogen and helium.
There is no pocket, the ship is protected from jump space by a field of normal spacetime that surrounds the ship that is generated/maintained by the jump drive and the hull cables.
Any hydrogen and helium vented as coolant will quickly move away from the ship as they are - hot.

The sequence is:
power plant runs at overclocked rate to fill jump capacitors - hydrogen coolant dumped overboard

the jump coils, the hull grid and whatever other handwavium (zuchai crystals) open the jump portal

portal is then closed with the ship in jump space, protected by a field
 
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There is no pocket, the ship is protected from jump space by a field of normal spacetime that surrounds the ship that is generated/maintained by the jump drive and the hull cables.
Any hydrogen and helium vented as coolant will quickly move away from the ship as they are - hot.
Maybe I should have quoted. I was responding to the Core Rulebook saying there was a pocket and it was puffed up with hydrogen.
I agree with your other post that THAT section in the rulebook is wrong, as this has never previously been a thing, and negates the need for special hull network material.
 
The article I quoted is in a Mongoose Journal and Mongoose has collectors (big solar sail like canopies that do not require hydrogen) as options in High Guard - how can I put this nicely

the rulebook is wrong, it is contradicted by MWM and High Guard.
Please keep in mind that not everyone owns JTAS Vol.2 or High Guard. So for many the Core Rulebook is the only source.
Btw. I can not find an article in my High Guard(2016) that contradicts the Core Rulebook(2016) in regards to how hydrogen is used by jump drives.
Since I don't own the Core Rulebook Update 2022 I can not say if it has the same explanation on how jump drive works as my version does.
 
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It does because we were not able to give feedback in time.

The rulebook uses an explanation that was popular fanon (and became canon in T4 but the less said about that edition the better)but contradicted by the vast majority of Traveller editions.

The Great Rift and High Guard make use of collectors, collectors do not use hydrogen, so the core rule book is contradicted.

MWM wrote that article originally for CT way back in GDW JTAS days.

The DGP crowd in their Starship Operator's Manual explained that the jump drive creates a bubble of normal space - no mention of hydrogen - but was likely where the hydrogen bubble fanon came from.

T4 FF&S2 was where the fanon became semi canon - it has since been removed for T5.

I research and read this stuff for fun :)
 
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I doubt anyone actually knows or understands how the jump drive works.

My interpretation of the current edition would be that everything happens within six minutes, where you flush upto sixty percent of the volume of the starship through the jump drive turbines in the form of processed or unprocessed fuel, which then has to go somewhere.

Being risk averse, I'd process the fuel before flushing it down the drain.

On the other hand, what exactly is unprocessed fuel?
 
I doubt anyone actually knows or understands how the jump drive works.
We are certainly talking about a fictional piece of equipment here. But on the other hand I can understand that if previously a different explanation was given in other Traveller material it can become a problem for some people. Others may take a pragmatic approach and go with the information that is available to them. Maybe jump drives work differently in different universes or maybe there are different jump drives within one universe that use different technology to achieve the same result.

Just out of curiosity: Is the hydogen consumption for a jump consistent throught Traveller editions and materials?
 
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I doubt anyone actually knows or understands how the jump drive works.

My interpretation of the current edition would be that everything happens within six minutes, where you flush upto sixty percent of the volume of the starship through the jump drive turbines in the form of processed or unprocessed fuel, which then has to go somewhere.

Being risk averse, I'd process the fuel before flushing it down the drain.

On the other hand, what exactly is unprocessed fuel?
MWM has described it in his article and in T5.
 
1. I think MegaTraveller changed that formula, with ecomies of scale.

2. And so do we, when customizing the drive.
MegaTraveller - the folks at DGP did such a poor job of adapting Striker and High Guard to a unified design system that they had to change the jump fuel requirement because the power plant fuel requirement went up. This actually had little effect for civilian ships with low jump numbers, but warships with lots of weapons, powerful m-drive and screens had to have lots of fuel for their large power plants. There was an official retcon which allowed you to only carry a few hours of fuel for a full combat rating, for cruising you cut down.

TNE kept the MegaTraveller jump fuel, and added requiring lots of fuel for HEPlaR. Again for civilian low jump numbers the difference is not appreciable, It is possible to go back to the classic 10% per jump number, but you will eat into your M-drive fuel. This is something I quite like. FF&S also had rules for reactionless thrusters and by T4 the jump fuel had gone back to 10% and ships usually used reactionless thruster plates for m-drives. By now they had done away with fusion power plants requiring lots of fuel.
 
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.
 
No, there were two editions that changed it.
Both MT and TNE used a reduced jump fuel requirement.
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...
 
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