Wilderness refueling

[RandyT0001]

One of the problems with refueling from an icy moon or asteroid in the outer zone is the fact that the frozen material you're landing on is gases. In fact the frozen water is probably buried under several kilometers of frozen gases. A very small amount of heat can cause them to expand back into gases with explosive force possibly causing damage to the ship or refueling equipment. For icy asteroids the problem is compounded by the fact that there is very little gravity to hold the gases making it more difficult to "skim". Icy moons might have enough gravity to keep the gases close to the surface long enough to "skim".

 

[Vile]

Joe Haldeman's The Forever War had some good parts about the dangers of very cold frozen places, and even 2000AD's Halo Jones (Book 2) had a bit at the end about it.

All of this, if taken into account, has some pretty far-reaching effects on your Traveller universe. Gathering hydrogen from asteroids and gas giants becomes a dangerous job best left to the professionals. Planets with liquid water, or easily-available water ice, become much more desirable sources of starship fuel. I've never been convinced that starports tend to be near sources of crude fuel, though - how many airports are built next to refineries or oil wells?

I could see big "Cloud City" floating refineries but with massive shielding and manoeuvre drives, maybe. Belters could specialise in extracting the frozen gases from asteroids, probably only for local use rather than export to the starport, unless there is no gas giant or easily accessible water in the system. Refined fuel would have to become much more commonly available - basically, any place except a Class E starport.

 

[RandyT0001]

All of this, if taken into account, has some pretty far-reaching effects on your Traveller universe. Gathering hydrogen from asteroids and gas giants becomes a dangerous job best left to the professionals. Planets with liquid water, or easily-available water ice, become much more desirable sources of starship fuel. I've never been convinced that starports tend to be near sources of crude fuel, though - how many airports are built next to refineries or oil wells?

I could see big "Cloud City" floating refineries but with massive shielding and manoeuvre drives, maybe. Belters could specialise in extracting the frozen gases from asteroids, probably only for local use rather than export to the starport, unless there is no gas giant or easily accessible water in the system. Refined fuel would have to become much more commonly available - basically, any place except a Class E starport.

I tend to agree. Most Traveller refs don't consider the implications of skimming the upper atmosphere of a gas giant with it's strong winds and wind shears. With such turbulence it is highly likely to be locally ionized leading to considrable lightning. And don't forget that lighnting here on Earth with only about 100 km thick atmosphere can reach several thousands of degrees. It's time to rethink the power in lighntning on a gas giant effects on the hull of a starship and it's internal electrical equipment and computers. It would be like getting hit with a pulse laser and an nuclear bomb's EMP. Thats why most regularly scheduled starships that travel between systems for big lines don't skim they buy their fuel from the starport. It's not cost effective to risk damage to the ship that might cause delays as it's repaired versus buying fuel at the starport (then refining it themselves if the ship is equiped with a purifier, if not, they'd buy refined fuel). The only ones that will skim gas giants (IMO) will be tramp traders flying free traders and far traders without passengers and cargo aboard (too risky).

 

[Dave Chase]

Or depending on the size of the ship, it might have its own specialize refueling small craft (ship).

Dave Chase

 

[Vile]

This could really do wonders for the street cred of those fuel shuttle jocks. They're going to be the toughest, meanest, most fearless and most sterile bunch of hombres on the flight deck ... :twisted:

 

[GamerDude]

what are the winds like on say, Jupiter, at the altitudes a craft would have to drop to for collecting fuel?

 

[BP]

All of this, if taken into account, has some pretty far-reaching effects on your Traveller universe. Gathering hydrogen from asteroids and gas giants becomes a dangerous job best left to the professionals.

Space is an extreme environment to begin with - thermal, radiation and hard vacuum extremes. Traveller has to make the presumption of dealing with this anyway as a commonly accepted 'norm'. So this doesn't really change anything in a TU.

... how many airports are built next to refineries or oil wells?

Though they do often have large storage tanks (called on-airport fuel farms) - and very large underground fuel lines to major distribution points - large airports need a lot of fuel. So in general they need access to fuel - with piping that fuel can come from hundreds of miles away.

MGT states that 'Starports and virtually any other facility that regularly hosts spacecraft will offer refuelling facilities.' [Core pg 140] - it doesn't actually speak to proximity of fuel sources (though, economically that would often be applied).


As to the exploding gas issue with mining ice on moons (I recall this as a plot gimmick in quite a few older Sci-Fi novels) - in general, this is not likely to be a big issue. The amount of heat required in these is generally coming from reaction engines, nuclear torch or lasers - most Traveller settings depend on Gravitics.

Water Ice on say Galilean surfaces is very cold - way below the point were frozen gases will vaporize under any kind of pressure at low heat differentials (mostly ablative) - unless digging very deep (kilometers)...

Traveller also uses Gravitics when 'scooping' - so the skimming is more like drinking from the outer gas layers (where the bulk of the free Hydrogen would be). The winds may be extemely fierce (though steady state 'hurricane' structures may have an eye) - but to a manuevering spaceship with gravitic compensators, that is not likely to run into anything in a gas environment, this is not likely to be a 'great big deal' (as long as one didn't just eat big and decide to look out a window).

Plasma discharges (lightning, etc.) are probably a bigger concern - but again, spaceships have to be able to deal with that anyway (as they already due to some extent in the RW).


MGT does deal with this - requiring a Pilot skill check when scooping. (Older editions referred to this as skimming IIRC - which infers a less realistic method).

 

[MrUkpyr]

Gas Giant Refueling: Die mods are you friend ( :twisted: ). The normal pilot skill check is for a relatively "calm" bit of atmosphere for the refueling, but you have to have found that calm bit.

Using the sensors to find that calm bit is an average check with no die mods, where 8+ on the check = found a spot.

If the players don't spend a minutes scanning for such a calm area I'll roll a d6....
1 = no mod to the roll
2 = -2 to the roll
3-5 = -4 to the roll
6 = -6 to the roll

If they fail the pilot roll, have something interesting happen. Lightning Strike, they hit some sort of beastie, gravitic problem and they go diving into atmosphere, etc etc etc.


Water Refueling: Here the pilot roll is simply how well they stay above the water. Failure means they dip into the water and something bad happens.


Ice Refueling: Pilot roll if chasing an asteroid, or when landing as normal.

 

[MrUkpyr]

On a different note from the above...

Ship Maintenance.

Has the ship been kept "Ship Shape and Bristol Fashion", or have they been skimping on monthly and annual maintenance?

If they have been skimping, then you can have all sorts of fun.

Some examples:
Fuel Purification System filters not changed = increasing misjump chance.
Fuel Pump valves stick = flooding ship with random gas or water.

The idea is that a starship is like a VERY VERY VERY expensive car. You not only have to do the normal tune ups, but you have to be constantly checking and fiddling with it to ensure it keeps running perfectly.

 

[Infojunky]

One of the problems with refueling from an icy moon or asteroid in the outer zone is the fact that the frozen material you're landing on is gases. In fact the frozen water is probably buried under several kilometers of frozen gases.

So what does where water have to do with refueling? Touch down suck all the wonderful Ammonia or Methane, you after Hydrogen right?

 

[Mithras]

Mmmm, still frozen as gasses though ...

 

[MrUkpyr]

One of the problems with refueling from an icy moon or asteroid in the outer zone is the fact that the frozen material you're landing on is gases. In fact the frozen water is probably buried under several kilometers of frozen gases.

So what does where water have to do with refueling? Touch down suck all the wonderful Ammonia or Methane, you after Hydrogen right?

You are correct! You are after Hydrogen, and honestly both Ammonia or Methane will work.

 

[RandyT0001]

Yes, the frozen hydrogen, methane and ammonia gases are what you're after on the surface of the icy moons and asteroids not the frozen water buried kilometers deep that's why I pointed out how deep the water would be. In all probability when you want to refuel from an icy moon or asteroid you're going to be operating under the triple point of hydrogen, ammonia and methane. The lower the pressure the less heat is required to make the phase change occur. If you send out a probe or apparatus that lands on the surface the latent heat within that probe will probably be warm enough to change the solidified material to gas, explosively.

I've put some thought into this problem and am finding it difficult to come up with a physical means to retrieve fuel from icy moons and asteroids. One idea I have is a mylar like shroud that forms a large bell at the end of the refueling hose that comes close to the surface but doesn't touch it. Located inside the bell next to it's connection to the hose there are several variable intensity lights to heat up the surface slowly to avoid explosive reactions,so that the gases are collected by the bell then pumped into the ship's tanks. Any other ideas on how this may be accomplished?

 

[MrUkpyr]

You know, I think at times we get drawn into a level of *too much* detail.

They land on the ice comet or asteroid, deploy the refueling unit, and gather the needed material.

If the players ask *how* it works, the answer is "using cool high tech that doesn't exist yet".

Honestly, most players don't care how it works, so long as the ST sounds convincing when something goes wrong. And going "one of the refueling valves has become jammed" doesn't need lots of information about how it all works.

 

[RandyT0001]

Some players and refs like that increased level of detail. Others just say I pilot my ship to the jump point, we jump and arrive at the next world followed by the ref asking for a roll to make a piloting skill check upon jumping in to cruise to the surface - begin new adventure. I try not to be judgemental about it. Whatever is fun for you and your players and me and my players is ok even when the level of detail is different, right? It's about having fun!

 

[MrUkpyr]

much snippage ... It's about having fun!

HERE HERE!! and point well made.
If my prev post came off as snarky, let me apologize to all as that was not my intent.

 

[BP]

Yes, the frozen hydrogen, methane and ammonia gases are what you're after on the surface of the icy moons and asteroids not the frozen water buried kilometers deep that's why I pointed out how deep the water would be. In all probability when you want to refuel from an icy moon or asteroid you're going to be operating under the triple point of hydrogen, ammonia and methane. The lower the pressure the less heat is required to make the phase change occur. If you send out a probe or apparatus that lands on the surface the latent heat within that probe will probably be warm enough to change the solidified material to gas, explosively.

I've put some thought into this problem and am finding it difficult to come up with a physical means to retrieve fuel from icy moons and asteroids. One idea I have is a mylar like shroud that forms a large bell at the end of the refueling hose that comes close to the surface but doesn't touch it. Located inside the bell next to it's connection to the hose there are several variable intensity lights to heat up the surface slowly to avoid explosive reactions,so that the gases are collected by the bell then pumped into the ship's tanks. Any other ideas on how this may be accomplished?

Active cooling. Water ice can be cut via ultrasonics (thermal energy is absorbed in breaking bonds) or properly tuned low intensity lasers (for optical absorption characteristics) and 'unthawed' in controlled conditions (i.e. pressure).

The 'explosion' is not like tons of tnt unless the heat/area/conditions are right. Dangerous pockets will typically require large amounts of heat to pressurize the pocket and exceed the threshold of the containing material - otherwise the constant heating from solar objects (sun/gas gaint) and tidal interaction would regularly be causing surface explosions (cool plot device like buring planet in Riddick movie - but not probably not sustainable except in exceeding rare cases). Quite a problem if shining a nuclear torch engine on the frozen surface or using laser torches to cut mutli-ton blocks of ice clear - but for normal ship re-fueling operations no more an issue than dealing with space in general...

I'm not saying this is a non-issue - just a readily addressed one. I'd equate this to being similiar to drilling for oil and natural gas. Inherently dangerous - but also routinely dealt with via knowledge, skill and applied technology.

 

[E.D.Quibell]

I'm not saying this is a non-issue - just a readily addressed one. I'd equate this to being similiar to drilling for oil and natural gas. Inherently dangerous - but also routinely dealt with via knowledge, skill and applied technology.

Good answer!

Best regards,

Ewan