Fuel Purification Plant

[Supplement Four]

Originally posted by Deniable:
so someone must have been thinking in the same direction. I wish they hadn't. I liked the old way.

That "new way" is only in TNE and which ever other Traveller rules set decides to use the same definition.

TNE has "contra grav". MT has "M-Drive overdrive".

TNE has point-defense sandcasters, too. In T20, the point-defense is dropped in favor of the way CT presents sandcasters.

In CT, the rules are different on some things.

The Escape Velocity rule is one of the things that's different.

 

[Supplement Four]

Just for grins, I thought I'd check a subsector and see how a ship with a 1G M-Drive would fare with the Escape Velocity rule.

So, I picked one of the most famous subsectors in Traveller. The Aramis subsector of the Spinward Marches.

There are two star clusters in this subsector that one would use a subsidized merchant. One, the Towers Cluster, is completely contained within the Aramis subsector.

The other, the Aramis Trace, has several worlds that stretch rimward down into the Rhylanor subsector, with the tip of the Trace even reaching into the Deneb sector.

Let's take a look...




I figure Class A and B starports have High Ports, so those will be no problem.

Size 7- worlds are small enough not to have a problem.

I figure Class C or D starports might have a High Port or some type of orbital docking facility (as described earlier in the thread with the 50 Starbases info). So, if a planet is Size 8+ with a Class C- starport, I'll note it. This is where the ship might have a problem.

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Towers Cluster
-------------------------------------------------
Jesedipere No prob (Size 7)
Rugbird No prob (Class B) Amber Zone
Junidy No prob (Size 4, Class B)
Yebab Problem? (Size 9, Class C)
Towers No prob (Size 4, Class B)
Nasemin No prob (Class B)
Feneteman No prob (Size 2)
Zykoca Problem? (Size 9, Class X) Red Zone
Pavanne No prob (Size 2)
Aramanx No prob (Size 6, Class B)
Carsten No prob (Size 4)</pre>[/QUOTE]So, if you were handing out subsidies, would you grant one to a captain of a Type R Fat Trader that sports a M-Drive rated at 1G? What if it's 20 ton launch was only rated at 1G too?

It doesn't look like a problem in the Towers Cluster.

There are only two worlds that are in question. First Zykoca is off limits to this subsidized vessel. But, that's OK because Zykoca is a Red Zone anyway!

The only other questionable place is Yebab. Size 9 with a Class C starport. My guess is that there is a high port associated with that starsystem because it's only one parsec from the major trade route running through Nasemin and Towers, and the Yebab system does have a gas giant. But, if this world doesn't have a high port, it's the only market off-limits to the subsidized merchant.

In addition, the subsidized merchant can land on every world in its subsidy except for the affor mentioned Yebab, Rugbird, and Nasemin. Those last two worlds definitely pose no problem, though, because they definitely have high ports associated with their starports.




OK, let's look at the Aramis Trace:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Aramis Trace
-------------------------------------------------
Natoko No Prob. (Size 5, Class B)
Aramis No Prob. (Size 6, Class A)
L'oeul d'Dieu No Prob. (Class B)
Reacher Problem? (Size 9, Class C) Amber Zone
Vinorian No Prob. (Class B)
Nutema No Prob. (Class B)
Margesi No Prob. (Size 5, Class A)
Saarinen No Prob. (Size 5, Class B)</pre>[/QUOTE]This subsidy route (the one the March Harrier uses), isn't bad either.

The only place where there might be a problem is at Reacher. Again, though, since it's only one parsec from the major trade route running through L'ouel d'Diew, Aramis, and Natoko, you'd think that Class C starport would have a high port.

Besides Reacher, the only other worlds the Harrier can't land on are L'oeul d'Dieu, Vinorian, and Nutema. All three of those have high ports (and L'oeul d'dieu is a water world, anyway).

Again, not a bad cluster of stars to run your vessel with it's 1G M-Drive, or even it's 1G launch!




I don't know how representative this is of the rest of the Imperium, but at least for this subsector, having a 1G drive is not that much of a handicap.

It would be interesting to see how a 1G ship fares up and down the Spinward Main.

 

[Supplement Four]

Just for grins, I thought I'd check a subsector and see how a ship with a 1G M-Drive would fare with the Escape Velocity rule.

So, I picked one of the most famous subsectors in Traveller. The Aramis subsector of the Spinward Marches.

There are two star clusters in this subsector that one would use a subsidized merchant. One, the Towers Cluster, is completely contained within the Aramis subsector.

The other, the Aramis Trace, has several worlds that stretch rimward down into the Rhylanor subsector, with the tip of the Trace even reaching into the Deneb sector.

Let's take a look...




I figure Class A and B starports have High Ports, so those will be no problem.

Size 7- worlds are small enough not to have a problem.

I figure Class C or D starports might have a High Port or some type of orbital docking facility (as described earlier in the thread with the 50 Starbases info). So, if a planet is Size 8+ with a Class C- starport, I'll note it. This is where the ship might have a problem.

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Towers Cluster
-------------------------------------------------
Jesedipere No prob (Size 7)
Rugbird No prob (Class B) Amber Zone
Junidy No prob (Size 4, Class B)
Yebab Problem? (Size 9, Class C)
Towers No prob (Size 4, Class B)
Nasemin No prob (Class B)
Feneteman No prob (Size 2)
Zykoca Problem? (Size 9, Class X) Red Zone
Pavanne No prob (Size 2)
Aramanx No prob (Size 6, Class B)
Carsten No prob (Size 4)</pre>[/QUOTE]So, if you were handing out subsidies, would you grant one to a captain of a Type R Fat Trader that sports a M-Drive rated at 1G? What if it's 20 ton launch was only rated at 1G too?

It doesn't look like a problem in the Towers Cluster.

There are only two worlds that are in question. First Zykoca is off limits to this subsidized vessel. But, that's OK because Zykoca is a Red Zone anyway!

The only other questionable place is Yebab. Size 9 with a Class C starport. My guess is that there is a high port associated with that starsystem because it's only one parsec from the major trade route running through Nasemin and Towers, and the Yebab system does have a gas giant. But, if this world doesn't have a high port, it's the only market off-limits to the subsidized merchant.

In addition, the subsidized merchant can land on every world in its subsidy except for the affor mentioned Yebab, Rugbird, and Nasemin. Those last two worlds definitely pose no problem, though, because they definitely have high ports associated with their starports.




OK, let's look at the Aramis Trace:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Aramis Trace
-------------------------------------------------
Natoko No Prob. (Size 5, Class B)
Aramis No Prob. (Size 6, Class A)
L'oeul d'Dieu No Prob. (Class B)
Reacher Problem? (Size 9, Class C) Amber Zone
Vinorian No Prob. (Class B)
Nutema No Prob. (Class B)
Margesi No Prob. (Size 5, Class A)
Saarinen No Prob. (Size 5, Class B)</pre>[/QUOTE]This subsidy route (the one the March Harrier uses), isn't bad either.

The only place where there might be a problem is at Reacher. Again, though, since it's only one parsec from the major trade route running through L'ouel d'Diew, Aramis, and Natoko, you'd think that Class C starport would have a high port.

Besides Reacher, the only other worlds the Harrier can't land on are L'oeul d'Dieu, Vinorian, and Nutema. All three of those have high ports (and L'oeul d'dieu is a water world, anyway).

Again, not a bad cluster of stars to run your vessel with it's 1G M-Drive, or even it's 1G launch!




I don't know how representative this is of the rest of the Imperium, but at least for this subsector, having a 1G drive is not that much of a handicap.

It would be interesting to see how a 1G ship fares up and down the Spinward Main.

 

[Supplement Four]

Originally posted by Supplement Four:
It would be interesting to see how a 1G ship fares up and down the Spinward Main.

And, if a spot was found where there is a problem for 1G vessels, a smart GM would make this known to the players.

"You've noticed you haven't seen one Fat Trader or Beowulf class free trader since you've been at the starport..."

 

[Supplement Four]

Originally posted by Supplement Four:
It would be interesting to see how a 1G ship fares up and down the Spinward Main.

And, if a spot was found where there is a problem for 1G vessels, a smart GM would make this known to the players.

"You've noticed you haven't seen one Fat Trader or Beowulf class free trader since you've been at the starport..."

 

[boomslang]

Originally posted by Supplement Four:
"You've noticed you haven't seen one Fat Trader or Beowulf class free trader since you've been at the starport..."

The major obstacle to Traders working the Spinward Main is the frequent unavailability of refined fuel -- there's even a world or two that's only on the Main for cartographic purposes: an E- starport on a Desert World with no GG; how any Trader ever manages to leave such a place is a tale I'd like to hear...

Frankly, the Beowulf class should come with a 20-dton collapsing tank as standard equipment...

 

[boomslang]

Originally posted by Supplement Four:
"You've noticed you haven't seen one Fat Trader or Beowulf class free trader since you've been at the starport..."

The major obstacle to Traders working the Spinward Main is the frequent unavailability of refined fuel -- there's even a world or two that's only on the Main for cartographic purposes: an E- starport on a Desert World with no GG; how any Trader ever manages to leave such a place is a tale I'd like to hear...

Frankly, the Beowulf class should come with a 20-dton collapsing tank as standard equipment...

 

[Supplement Four]

Reading an article about Gas Giants from the Traveller perspective in Pegasus Magazine...




... And, I've seen this before too: Hydrogen in GG atmospheres is more prevalent when the GG is closer to the star. So, when picking a GG to skim, pick the one that is closest to the system's star.

... Wind speeds within a gas giant's atmosphere have been estimated to be gusting at 500 meters per second (1200 mph). Talk about wind turbulence! Talk about shaking the ship apart! By comparison, jet streams on earth reach speeds of 160 meters per second (350 mph).

... The article suggests it would be much, much easier to land on some other solar body, exit your ship, and dig up some ice with a shovel (well, you'll probably need a good, powered shovel).

... The article suggest that GMs consider hull stress and expensive damage if players skim frequently. (Remember my house rules up-thread!).

... Some portions of a Gas Giant's atmosphere are sometimes actually liquid. Traveller ships skimming, moving at the speeds needed to obtain escape velocity, and then slamming into a liquid pocket probably won't bode well for the Travellers inside the ship.

... The small ring of Jupiter is made up of tiny particles, most of them microscopic so that they're no bigger than the particles that make up cigarette smoke. This wouldn't even screen a ship from radar dection! And, it certainly can't stop a missile. Traveller GMs may want to allow a ship to use Jupiter ring as a sandscreen, though, as if a sandcaster had been fired to protect the ship.

... Trojan Points make excellent spots for asteroid miners, orbital ports and facilities, and hiding pirates.

 

[Supplement Four]

Reading an article about Gas Giants from the Traveller perspective in Pegasus Magazine...




... And, I've seen this before too: Hydrogen in GG atmospheres is more prevalent when the GG is closer to the star. So, when picking a GG to skim, pick the one that is closest to the system's star.

... Wind speeds within a gas giant's atmosphere have been estimated to be gusting at 500 meters per second (1200 mph). Talk about wind turbulence! Talk about shaking the ship apart! By comparison, jet streams on earth reach speeds of 160 meters per second (350 mph).

... The article suggests it would be much, much easier to land on some other solar body, exit your ship, and dig up some ice with a shovel (well, you'll probably need a good, powered shovel).

... The article suggest that GMs consider hull stress and expensive damage if players skim frequently. (Remember my house rules up-thread!).

... Some portions of a Gas Giant's atmosphere are sometimes actually liquid. Traveller ships skimming, moving at the speeds needed to obtain escape velocity, and then slamming into a liquid pocket probably won't bode well for the Travellers inside the ship.

... The small ring of Jupiter is made up of tiny particles, most of them microscopic so that they're no bigger than the particles that make up cigarette smoke. This wouldn't even screen a ship from radar dection! And, it certainly can't stop a missile. Traveller GMs may want to allow a ship to use Jupiter ring as a sandscreen, though, as if a sandcaster had been fired to protect the ship.

... Trojan Points make excellent spots for asteroid miners, orbital ports and facilities, and hiding pirates.

 

[boomslang]

Originally posted by Supplement Four:
... Wind speeds within a gas giant's atmosphere have been estimated to be gusting at 500 meters per second (1200 mph). Talk about wind turbulence! Talk about shaking the ship apart! By comparison, jet streams on earth reach speeds of 160 meters per second (350 mph).

Important Safety Tip: When skimming fuel, run with the prevailing winds at that latitude, not against them, to minimize loss of momentum.

 

[boomslang]

Originally posted by Supplement Four:
... Wind speeds within a gas giant's atmosphere have been estimated to be gusting at 500 meters per second (1200 mph). Talk about wind turbulence! Talk about shaking the ship apart! By comparison, jet streams on earth reach speeds of 160 meters per second (350 mph).

Important Safety Tip: When skimming fuel, run with the prevailing winds at that latitude, not against them, to minimize loss of momentum.

 

[boomslang]

Originally posted by Supplement Four:
... Some portions of a Gas Giant's atmosphere are sometimes actually liquid. Traveller ships skimming, moving at the speeds needed to obtain escape velocity, and then slamming into a liquid pocket probably won't bode well for the Travellers inside the ship.

Again, you can find all the gas you need up at about 1/2 standard atmo pressure; you can stay well out of the soup, because elemental hydrogen is lighter than any other atmo component, and tends to rise to the top... but mind your RADAR/LADAR/Densitometer forward sweeps nonetheless...

 

[boomslang]

Originally posted by Supplement Four:
... Some portions of a Gas Giant's atmosphere are sometimes actually liquid. Traveller ships skimming, moving at the speeds needed to obtain escape velocity, and then slamming into a liquid pocket probably won't bode well for the Travellers inside the ship.

Again, you can find all the gas you need up at about 1/2 standard atmo pressure; you can stay well out of the soup, because elemental hydrogen is lighter than any other atmo component, and tends to rise to the top... but mind your RADAR/LADAR/Densitometer forward sweeps nonetheless...

 

[Straybow]

Originally posted by Supplement Four:
OK, let's look at your question...

I would answer this by citing the CT vehicle design rules in Striker. There, it plainly states that grav craft must devote some of their G rating to just staying afloat and beating the world's gravity.

Any left-over G rating is used for to maneuver the grav craft, and it is this rating that actually rates the vessel in its description (the G of lift needed to beat the world's gravity is not part of its description rating).

The CT vehicle design rules in Striker plainly say that. And, this consistent whether you're talking about a grav belt, a G-Carrier, or even a starship (all mentioned on different pages of Striker design rules).

Simple. We already round the "G" up from 9.81m/s to 10m/s. We just round up a little more.

Alternately, we say that near a planet's surface gravity does not act like a point source, and therefore an air/raft, G-carrier, or grav-driven spacecraft can "lift" against slightly more than the rated G. Or some other handwave.

 

[Straybow]

Originally posted by Supplement Four:
1. Why do CT grav vehicle design rules in Striker read the way they do?
2. Why does Stiker, pg. 41 of Book 2 explicitly state ...
3. Why does Andy Lilly ...
4. Why does the LKW ...
5. Why does the Book 2 space combat movement rules ...
6. Why does Book 6 show escape velocity ...
7. And, are all the high ports and port-to-ground shuttle services ...

Canon vs. vector math: vector math wins.

But, I like the system CT has. It lends itself well to roleplaying. It adds depth and detail to the gaming universe.

It makes traveling from one world to another that much more interesting...that much more believeable.

I don't know of any unobtanium that would be cheap, rugged and effective enough to coat our starships. So our heat shields must be made of handwavium...

Hyperdense hulls, constructed in zero G, using graviton manipulation to allign the molecules?

They provide decent protection vs. laser fire. I have no problem believing they can provide protection on re-entry too.

Back on topic: that heat shielding doesn't let us land or skim unless we have the G-rating? Kinda like the shuttle can't land without power... Oh, never mind.

Most of the CT rules were made in gross ignorance of aerodynamics, ballistics, rocketry, orbital mechanics, and of what little we knew about gas giants in the '70s.

Skimming wouldn't even need the ½ std atm boomslang posited. That ½ bar corresponds to 12k feet here on earth. Scramjets can work well above 100k feet, which is well under 0.01 bar by back-of-the-envelope calc.

Ramjets/scramjets use dynamic pressure to compress the intake gas to 12+ atm if my other b.o.t.e. calc is correct. The momentum of a massive, hyperdense hulled spaceship should be enough to liquify hydrogen in the scoop skimming in the low pressure (p < 0.1 bar) region.

 

[Straybow]

Originally posted by boomslang:

Originally posted by Supplement Four:
Otherwise, if Book 2 did it your way...if all a PC had to do in designing his ship was say, "I want my ship to be built to use unrefined fuel," then why would there be a unrefined jump penalty DM listed in Book 2 at all?

Because there are some ships which are specifically designed to require refined fuel precisely in order to make them less attractive to hijackers.

The fuel purifiers in the military (and quasi-military) vessels make more sense than what you're proposing.

Um, so, according to B2, how much do they displace and how much do they cost?

B2 is written B5-agnostic; nowhere in any version of B2 is there any evidence of the existence of shipboard fuel purifiers. They are a strictly post-HG artifact, but even later versions of B2 are BT-complete and do not require anything from later Books.

Sorry, but that's how it's written. Shipboard fuel purifiers just aren't there in B2, no matter how hard you care to look for them...

The idea of requiring refined fuel to limit the usefulness as a pirate vessel makes a bit of sense. But still that leaves the question open, and as LBB2 is ignorant of fuel purifiers, then we retrofit the letter of LBB2 to conform to the use of fuel purifiers.

They can be added to a ship that requires refined fuel. Given the cost savings it would be profitable to do so in the vast majority of cases.

If refined fuel were priced sensibly (in recognition of cheap purification costs) it should be ~150/ton. Now it is not profitable to take up cargo space for a purifier.

 

[tinker123]

Originally posted by Straybow:

Skimming wouldn't even need the ½ std atm boomslang posited. That ½ bar corresponds to 12k feet here on earth. Scramjets can work well above 100k feet, which is well under 0.01 bar by back-of-the-envelope calc.

Ramjets/scramjets use dynamic pressure to compress the intake gas to 12+ atm if my other b.o.t.e. calc is correct. The momentum of a massive, hyperdense hulled spaceship should be enough to liquify hydrogen in the scoop skimming in the low pressure (p < 0.1 bar) region.

So I guess you could scoop fuel off any planet with an atmosphere? Of course, the people who live on the planet and breathe the atmosphere might have an opinion about letting you steal some of their air

 

[tinker123]

Originally posted by Straybow:

Skimming wouldn't even need the ½ std atm boomslang posited. That ½ bar corresponds to 12k feet here on earth. Scramjets can work well above 100k feet, which is well under 0.01 bar by back-of-the-envelope calc.

Ramjets/scramjets use dynamic pressure to compress the intake gas to 12+ atm if my other b.o.t.e. calc is correct. The momentum of a massive, hyperdense hulled spaceship should be enough to liquify hydrogen in the scoop skimming in the low pressure (p < 0.1 bar) region.

So I guess you could scoop fuel off any planet with an atmosphere? Of course, the people who live on the planet and breathe the atmosphere might have an opinion about letting you steal some of their air

 

[Supplement Four]

Originally posted by Straybow:
Canon vs. vector math: vector math wins.

Are you disputing the Escape Velocity rule?

Is not the movement formula in Book 2 Space Combat vector math?

Set your 1G vessel on a 1G world and use that formula to lift off. Tell me how far you get using that vector math expression.

 

[Supplement Four]

Originally posted by Straybow:
Canon vs. vector math: vector math wins.

Are you disputing the Escape Velocity rule?

Is not the movement formula in Book 2 Space Combat vector math?

Set your 1G vessel on a 1G world and use that formula to lift off. Tell me how far you get using that vector math expression.