Supplement Four
SOC-14 5K
My question would be, "Why, though? What's your reasoning for them only being "ex-military" surplus?"
Fuel Purification Plant
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Supplement Four
SOC-14 5K
My question would be, "Why, though? What's your reasoning for them only being "ex-military" surplus?"
Straybow
SOC-14 1K
I don't think so. Fuel is hydrogen, not hydrazine or the like. "Unrefined" fuel isn't like crude oil that has to be fractionated, cracked, etc into smaller but still complex organics.
"Unrefined" is hydrogen that has traces of other stuff in it; the refiner eliminates those. A refiner can turn other hydrogen-bearing substances into fuel, though it takes more time and effort.
Using electrolysis to obtain Hydrogen from simple molecules (water, methane, ammonia) is a very straight-forward operation. Larger molecules mostly take more energy.
Icosahedron
SOC-14 1K
Another take would be that unrefined fuel is Hydrogen, refined fuel is Deuterium or Tritium, or Tritium-enriched Deuterium, or something.
Or perhaps the 'fuel scoops' filter Deuterium from Hydrogen and Deuterium is Unrefined fuel which is then Tritium-enriched to create Refined fuel?
Or perhaps the 'fuel scoops' filter Deuterium from Hydrogen and Deuterium is Unrefined fuel which is then Tritium-enriched to create Refined fuel?
Icosahedron
SOC-14 1K
Another take would be that unrefined fuel is Hydrogen, refined fuel is Deuterium or Tritium, or Tritium-enriched Deuterium, or something.
Or perhaps the 'fuel scoops' filter Deuterium from Hydrogen and Deuterium is Unrefined fuel which is then Tritium-enriched to create Refined fuel?
Or perhaps the 'fuel scoops' filter Deuterium from Hydrogen and Deuterium is Unrefined fuel which is then Tritium-enriched to create Refined fuel?
Supplement Four
SOC-14 5K
The Realities of Gas Giant Skimming
I've been reading through all things CT lately, and I come across Sup 3: The Spinward Marches.
There, on pg. 36, it casually states how a starport's primary function is to provide fuel for starships. But, should fuel be unavailable for some reason, that a ship can easily obtain unrefined fuel from world oceans, by chipping ice, or by skimming at a gas giant.
It makes it sound so simple. I mean, it can't be that hard, can it? The Traveller Book says it takes about 8 hours to skim at a gas giant--with no reference to a throw that needed to be made (like the throw listed for reviving people from low berth) or any possible damage to the ship.
It is only when we get to Sup 5: Lightning Class Cruisers that we get the real story.
Check out pg. 43 on the section detailing refuelling.
Should one of those 60,000 cruisers decide to dive into the GG itself, not sending its fuel shuttles, the shuttles themselves, docked to the underside of the ship, can be ripped from their docking clamps.
Severe buffeting may cause the fuel deck to leak or buckle.
And, the atmospheric turbulence can cause internal damage to the ship's maneuver drive.
Faced with one of those prospects, gas giant refuelling doesn't look at profitable as it once did, does it?
Of course, the cruiser's fuel shuttles are built to withstand GG turbulance. The pilots are specifically trained in skimming procedures.
Which leaves me to the thought: The reason civilian craft aren't fitted with fuel purifiers (the reason they're not included in Book 2 ship design) is because (A) normal civilian pilots aren't trained for the hazards of GG skimming, and (B) normal civilian ships aren't specifically designed to withstand turbulance and therefore may take damage the way the Lightning Class Cruisers do.
Makes sense to me.
I've been reading through all things CT lately, and I come across Sup 3: The Spinward Marches.
There, on pg. 36, it casually states how a starport's primary function is to provide fuel for starships. But, should fuel be unavailable for some reason, that a ship can easily obtain unrefined fuel from world oceans, by chipping ice, or by skimming at a gas giant.
It makes it sound so simple. I mean, it can't be that hard, can it? The Traveller Book says it takes about 8 hours to skim at a gas giant--with no reference to a throw that needed to be made (like the throw listed for reviving people from low berth) or any possible damage to the ship.
It is only when we get to Sup 5: Lightning Class Cruisers that we get the real story.
Check out pg. 43 on the section detailing refuelling.
Should one of those 60,000 cruisers decide to dive into the GG itself, not sending its fuel shuttles, the shuttles themselves, docked to the underside of the ship, can be ripped from their docking clamps.
Severe buffeting may cause the fuel deck to leak or buckle.
And, the atmospheric turbulence can cause internal damage to the ship's maneuver drive.
Faced with one of those prospects, gas giant refuelling doesn't look at profitable as it once did, does it?
Of course, the cruiser's fuel shuttles are built to withstand GG turbulance. The pilots are specifically trained in skimming procedures.
Which leaves me to the thought: The reason civilian craft aren't fitted with fuel purifiers (the reason they're not included in Book 2 ship design) is because (A) normal civilian pilots aren't trained for the hazards of GG skimming, and (B) normal civilian ships aren't specifically designed to withstand turbulance and therefore may take damage the way the Lightning Class Cruisers do.
Makes sense to me.
Supplement Four
SOC-14 5K
The Realities of Gas Giant Skimming
I've been reading through all things CT lately, and I come across Sup 3: The Spinward Marches.
There, on pg. 36, it casually states how a starport's primary function is to provide fuel for starships. But, should fuel be unavailable for some reason, that a ship can easily obtain unrefined fuel from world oceans, by chipping ice, or by skimming at a gas giant.
It makes it sound so simple. I mean, it can't be that hard, can it? The Traveller Book says it takes about 8 hours to skim at a gas giant--with no reference to a throw that needed to be made (like the throw listed for reviving people from low berth) or any possible damage to the ship.
It is only when we get to Sup 5: Lightning Class Cruisers that we get the real story.
Check out pg. 43 on the section detailing refuelling.
Should one of those 60,000 cruisers decide to dive into the GG itself, not sending its fuel shuttles, the shuttles themselves, docked to the underside of the ship, can be ripped from their docking clamps.
Severe buffeting may cause the fuel deck to leak or buckle.
And, the atmospheric turbulence can cause internal damage to the ship's maneuver drive.
Faced with one of those prospects, gas giant refuelling doesn't look at profitable as it once did, does it?
Of course, the cruiser's fuel shuttles are built to withstand GG turbulance. The pilots are specifically trained in skimming procedures.
Which leaves me to the thought: The reason civilian craft aren't fitted with fuel purifiers (the reason they're not included in Book 2 ship design) is because (A) normal civilian pilots aren't trained for the hazards of GG skimming, and (B) normal civilian ships aren't specifically designed to withstand turbulance and therefore may take damage the way the Lightning Class Cruisers do.
Makes sense to me.
I've been reading through all things CT lately, and I come across Sup 3: The Spinward Marches.
There, on pg. 36, it casually states how a starport's primary function is to provide fuel for starships. But, should fuel be unavailable for some reason, that a ship can easily obtain unrefined fuel from world oceans, by chipping ice, or by skimming at a gas giant.
It makes it sound so simple. I mean, it can't be that hard, can it? The Traveller Book says it takes about 8 hours to skim at a gas giant--with no reference to a throw that needed to be made (like the throw listed for reviving people from low berth) or any possible damage to the ship.
It is only when we get to Sup 5: Lightning Class Cruisers that we get the real story.
Check out pg. 43 on the section detailing refuelling.
Should one of those 60,000 cruisers decide to dive into the GG itself, not sending its fuel shuttles, the shuttles themselves, docked to the underside of the ship, can be ripped from their docking clamps.
Severe buffeting may cause the fuel deck to leak or buckle.
And, the atmospheric turbulence can cause internal damage to the ship's maneuver drive.
Faced with one of those prospects, gas giant refuelling doesn't look at profitable as it once did, does it?
Of course, the cruiser's fuel shuttles are built to withstand GG turbulance. The pilots are specifically trained in skimming procedures.
Which leaves me to the thought: The reason civilian craft aren't fitted with fuel purifiers (the reason they're not included in Book 2 ship design) is because (A) normal civilian pilots aren't trained for the hazards of GG skimming, and (B) normal civilian ships aren't specifically designed to withstand turbulance and therefore may take damage the way the Lightning Class Cruisers do.
Makes sense to me.
Supplement Four
SOC-14 5K
Playing the heck out of GG Skimming...
If you look at pg. 43 of Sup 5, there's plenty of rules there you can modify for civilan vessels skimming at gas giants.
Pilot skill can come into play as a beneficial DM on some of the throws.
BUT, WHY DON'T YOU TRY THIS...
A rule I've used in my games focuses on the ship's pilot and navigator. Have the Navigator throw 2D and add Nav skill. This represents the navigator's best attempt at giving the pilot a course through the least dangerous areas of the GG's upper atmosphere.
Then, as the ship acutally follows that course in order to skim, have the pilot throw 2D minus Pilot skill, trying to roll the Nav number or less.
If the pilot's roll is less than the Nav number, then the ship made it through the GG's atmo without incident. If the pilot's roll is greater than the Nav number, then roll damage on the ship as if it were hit in space combat (Book 2 damage table). The ship's engineer can effect repairs per normal space combat rules (one roll of 9+ allowed per 15 minutes).
It takes 3D minus pilot skill trips through the GG like this to completely refuel the ship. Each trip takes about an hour to perform. The average time, according to The Traveller Book, to refuel at a GG is 8 hours. The average roll on 3D is 10, and if you subtract the average competent pilot skill of Pilot-2, you get an average of 8 hours using this method.
The navigator can make course adjustments to his initial skimming flight plan each trip, so allow the navigator to re-roll the Nav roll at the completion of one trip. If the Nav roll is high, he'll stick with the original plan and not alter course.
Using this rule, your PCs Navigators and Pilots can take this opportunity to shine.
Engineers, and the rest of the crew, if not fixing turbulance damage, can be busy overseeing the refueling process. GMs may want to get creative with Hull or Cargo Bay damage results from damage, instead describing how the LHyd influx pipe is cracked with all the buffeting, and now liquid hydrogen is filling up engineering compartment C. Or, some such creative problem the players will have to deal with. Maybe an antenna was blown off the hull of the ship, and once the vessel is out of the upper atmosphere of the GG, someone will have to go EVA on the hull to fix it. Or, maybe an intake baffel was damaged, and the engineer has to shut it down. Now, refueling will take twice as long--exposing the ship to more damage.
The GM's imagination is the limit.
On the rolls above, GMs may wish to address character stats. Simply pick a number, in the normal CT way, and say, "If the Navigator has EDU 9+, then he'll add +1 to his Nav roll." Or, maybe "If the Pilot's DEX is 10+, allow a -2DM on the 3D roll that determines the number of trips required to skim a full tank."
Something like that.
BTW, if you're a UGM user, you can easily use the UGM tasks to include stats on these rolls.
Let's look at an example.
Luukhan Pershiire is navigator for the Type A2 Far Trader ADROIT PURSUIT. He's got Navigation-2 and EDU 7. Using the suggested stat DMs above (that I made up on the fly...you may want to put some more thought into them for your game), Luukhan will plot the course the PURSUIT will take through the upper atmosphere of the gas giant filling its bridge port.
He rolls 2D and gets a 4. +2 for skill. The Nav roll becomes 6.
Now, the pilot must dive through the gas giant, using the navigator's plot.
The ship's pilot is Dexter Bryte, Pilot-1. He'll roll 2D -1, attempting to throw 6 or less. This represents about an hour of time in the game as the pilot dives through the gas giant's upper atmo with fuel cocks open.
Dexter throws 8 on the dice, minus 1, which equals 7. Not so good.
The GM then throws on the Book 2 damage table as if the ship had been hit in space combat. The result is hull damage. Being nice, the GM decides that the pressures in the atmo of the gas giant cracked the seal on the port cargo airlock. It's nothing to worry about now, as the inner lock hatch will keep the cargo deck's integrity. But, it will be expensive and.or time consuming to repair. Maybe it's just the seal that needs replacing, and maybe the door has buckled under the strain of ship's maneuvers and high G. The engineer won't know until he can get outside, either by Vacc Suit or while the ship is dirtside, to check it out.
The "cheap" method of skimming fuel for free just became a little more costly than expected.
The GM, giving the PCs a relatively inconsequential problem (they've just got to fix the outer cargo hatch at this point, and that can be done later) has already decided that if another hull result pops up from a failed pilot roll, then the inner lock may go next, exposing the cargo deck to explosive decompression (and now we're talking damage to the cargo as well).
Depending on the player playing the ship's engineer, a GM may want to give the engineer an heads up on this. Maybe the GM will give the engineer a roll to assess the damage.
If he makes it, the engineer may say to the captain, "Cap'n, that's a pretty hard blow she took during that last maneuver. I dunno if the outer hatch will hold. We may want to think about abortin' the skim and headin' back dirtside to buy some fuel."
"That's two days travel and 500 credits a ton, chief. Are you sure?"
"Well, it's your call, Cap'n. But, if we press on, I'd at least want to decompress the hold."
"We've got live cattle down there, chief! We can't do that!"
"Damage 'll be more costly if the inner hatch buckles and we loose the cattle plus other cargo. I say we head dirtside."
"We just don't have the credits, chief. We blew it all on the spec cargo in the hold. We can't even afford 100 credits a ton for the unrefined stuff. The cattle is the least expensive cargo we're carrying. Let's re-tool our flight plan and give 'er another go."
"Your the boss, skip."
So, at this point, the GM determines how many trips it will take the PURSUIT to dive through the gas giant and skim enough fuel to fill the ship's tanks.
Secretly, the GM rolls 3D -2 behind his screen. The -2DM is for Pilot skill. The pilot's EDU is 5, so there's no extra DM bonus there.
The GM makes this roll in secret because, although the navigator can predict how long his flight plan will take to complete, there are several factors in fueling that are unpredictable--density of LHyd being one of them; amount scooped in a trip being another. Turbulance is another factor. So, I suggest making this roll in secret. The navigator's prediction of how long skimming will take is equal to the average of a 3D roll minus pilot skill. The average of 3D is 10. Subtract pilot (Dexter is Pilot-2) and get an average of 8 hours.
So, in secret, the GM makes this roll. He throws 3D and gets 7. Minus 2. It will take 5 trips, at about an hour each, to refuel the PURSUIT.
This is a fairly fortunate roll, but the players really have no idea of their good fortune at this point. It could be 16 hours for all they know.
On trip #2, the ship's navigator thinks he can do better, so he re-tools the nav plan and makes the nav roll again. But, this time he does even worse. He throws 2D and rolls snake eyes. +2 for skill, and the new Nav roll becomes 4.
Oh crap. This is a tough one. The GM describes the PURSUIT diving into the GG and then getting broadsided by a atmospheric storm. It's a vortex, or a tornado, swirling around at impossible speeds. If the pilot misses his roll, then the GM is determined to make whatever space combat damage that pops up much worse than the first time.
It's a tense situation. The entire ship is rattling. Had there been passengers aboard, the GM might have one of them throw up. At the minimum, a roll on the NPC reaction chart to reflect the passenger's demeanor against the crew would be in order. The PURSUIT's captain, though, was smart. He didn't bring civies with him while skimming. This was strickly a spec trade run.
So, the pilot needs to roll 4- on a throw of 2D -2. He throws, gets a 6 on the roll, and modifies it to a 4.
YEAHH!!!
The entire gaming table explodes. The player playing the pilot is beaming.
The GM describes how, deftly, the pilot rolled the ship, taking the main turblance from the vortex on the aft section of the vessel. Then, he increased the thrust and escaped the vortex, up through its center, before the ship hit the other side.
"Good thing," the GM says, remembering that he was about to let the players have it bad with damage, "that thing was the size of Canada. Your pilot here got you out of it. And now, you've got more fuel in your tanks, but not enough. Care to continue?"
Behind his screen, the GM makes note that 2 of the 5 hours for refueling are completed.
"How full are the tanks?" The player playing the engineer says.
But, the GM, not wanting to tip off the secret time roll, doesn't tell him they're 40% full. He downplays it a bit, to throw the players off."
"You look at the gauge," the GM says to the player, "it reads 18.547% full."
Boosted by the fantastic performance by the ship's pilot, the navigator attempts a third time to alter his course prediction. He makes the Nav roll again. 2D +2. This time, he rolls 8, plus 2, equals 10.
Not a bad roll this time. With the pilot's -2DM, it's as good as one can get. Even if the pilot rolls a 12, his DM will get him under 10.
So, from here on out, the Nav will stick with this plan. It's the best that can be done.
And, all piloting rolls will automatically succeed now, given the Nav's roll.
So, the GM decides to cover the remaining three trips quickly.
"When you dive back down into the gas giant, you see smooth clouds. It's the far side of the storm you hit, and it looks like smooth sailing. Three hours, three dives later, you're done. Full tanks, and one damaged port cargo hatch. It got a little tricky there for a moment, but you made it. You hear a 'moooo' from the cargo deck. Maybe it was one of the cows down there thanking you. Are we moving to jump point now? Or, do you want to go EVA and check out that cargo hatch before the ship jumps...?"
If you look at pg. 43 of Sup 5, there's plenty of rules there you can modify for civilan vessels skimming at gas giants.
Pilot skill can come into play as a beneficial DM on some of the throws.
BUT, WHY DON'T YOU TRY THIS...
A rule I've used in my games focuses on the ship's pilot and navigator. Have the Navigator throw 2D and add Nav skill. This represents the navigator's best attempt at giving the pilot a course through the least dangerous areas of the GG's upper atmosphere.
Then, as the ship acutally follows that course in order to skim, have the pilot throw 2D minus Pilot skill, trying to roll the Nav number or less.
If the pilot's roll is less than the Nav number, then the ship made it through the GG's atmo without incident. If the pilot's roll is greater than the Nav number, then roll damage on the ship as if it were hit in space combat (Book 2 damage table). The ship's engineer can effect repairs per normal space combat rules (one roll of 9+ allowed per 15 minutes).
It takes 3D minus pilot skill trips through the GG like this to completely refuel the ship. Each trip takes about an hour to perform. The average time, according to The Traveller Book, to refuel at a GG is 8 hours. The average roll on 3D is 10, and if you subtract the average competent pilot skill of Pilot-2, you get an average of 8 hours using this method.
The navigator can make course adjustments to his initial skimming flight plan each trip, so allow the navigator to re-roll the Nav roll at the completion of one trip. If the Nav roll is high, he'll stick with the original plan and not alter course.
Using this rule, your PCs Navigators and Pilots can take this opportunity to shine.
Engineers, and the rest of the crew, if not fixing turbulance damage, can be busy overseeing the refueling process. GMs may want to get creative with Hull or Cargo Bay damage results from damage, instead describing how the LHyd influx pipe is cracked with all the buffeting, and now liquid hydrogen is filling up engineering compartment C. Or, some such creative problem the players will have to deal with. Maybe an antenna was blown off the hull of the ship, and once the vessel is out of the upper atmosphere of the GG, someone will have to go EVA on the hull to fix it. Or, maybe an intake baffel was damaged, and the engineer has to shut it down. Now, refueling will take twice as long--exposing the ship to more damage.
The GM's imagination is the limit.
On the rolls above, GMs may wish to address character stats. Simply pick a number, in the normal CT way, and say, "If the Navigator has EDU 9+, then he'll add +1 to his Nav roll." Or, maybe "If the Pilot's DEX is 10+, allow a -2DM on the 3D roll that determines the number of trips required to skim a full tank."
Something like that.
BTW, if you're a UGM user, you can easily use the UGM tasks to include stats on these rolls.
Let's look at an example.
Luukhan Pershiire is navigator for the Type A2 Far Trader ADROIT PURSUIT. He's got Navigation-2 and EDU 7. Using the suggested stat DMs above (that I made up on the fly...you may want to put some more thought into them for your game), Luukhan will plot the course the PURSUIT will take through the upper atmosphere of the gas giant filling its bridge port.
He rolls 2D and gets a 4. +2 for skill. The Nav roll becomes 6.
Now, the pilot must dive through the gas giant, using the navigator's plot.
The ship's pilot is Dexter Bryte, Pilot-1. He'll roll 2D -1, attempting to throw 6 or less. This represents about an hour of time in the game as the pilot dives through the gas giant's upper atmo with fuel cocks open.
Dexter throws 8 on the dice, minus 1, which equals 7. Not so good.
The GM then throws on the Book 2 damage table as if the ship had been hit in space combat. The result is hull damage. Being nice, the GM decides that the pressures in the atmo of the gas giant cracked the seal on the port cargo airlock. It's nothing to worry about now, as the inner lock hatch will keep the cargo deck's integrity. But, it will be expensive and.or time consuming to repair. Maybe it's just the seal that needs replacing, and maybe the door has buckled under the strain of ship's maneuvers and high G. The engineer won't know until he can get outside, either by Vacc Suit or while the ship is dirtside, to check it out.
The "cheap" method of skimming fuel for free just became a little more costly than expected.
The GM, giving the PCs a relatively inconsequential problem (they've just got to fix the outer cargo hatch at this point, and that can be done later) has already decided that if another hull result pops up from a failed pilot roll, then the inner lock may go next, exposing the cargo deck to explosive decompression (and now we're talking damage to the cargo as well).
Depending on the player playing the ship's engineer, a GM may want to give the engineer an heads up on this. Maybe the GM will give the engineer a roll to assess the damage.
If he makes it, the engineer may say to the captain, "Cap'n, that's a pretty hard blow she took during that last maneuver. I dunno if the outer hatch will hold. We may want to think about abortin' the skim and headin' back dirtside to buy some fuel."
"That's two days travel and 500 credits a ton, chief. Are you sure?"
"Well, it's your call, Cap'n. But, if we press on, I'd at least want to decompress the hold."
"We've got live cattle down there, chief! We can't do that!"
"Damage 'll be more costly if the inner hatch buckles and we loose the cattle plus other cargo. I say we head dirtside."
"We just don't have the credits, chief. We blew it all on the spec cargo in the hold. We can't even afford 100 credits a ton for the unrefined stuff. The cattle is the least expensive cargo we're carrying. Let's re-tool our flight plan and give 'er another go."
"Your the boss, skip."
So, at this point, the GM determines how many trips it will take the PURSUIT to dive through the gas giant and skim enough fuel to fill the ship's tanks.
Secretly, the GM rolls 3D -2 behind his screen. The -2DM is for Pilot skill. The pilot's EDU is 5, so there's no extra DM bonus there.
The GM makes this roll in secret because, although the navigator can predict how long his flight plan will take to complete, there are several factors in fueling that are unpredictable--density of LHyd being one of them; amount scooped in a trip being another. Turbulance is another factor. So, I suggest making this roll in secret. The navigator's prediction of how long skimming will take is equal to the average of a 3D roll minus pilot skill. The average of 3D is 10. Subtract pilot (Dexter is Pilot-2) and get an average of 8 hours.
So, in secret, the GM makes this roll. He throws 3D and gets 7. Minus 2. It will take 5 trips, at about an hour each, to refuel the PURSUIT.
This is a fairly fortunate roll, but the players really have no idea of their good fortune at this point. It could be 16 hours for all they know.
On trip #2, the ship's navigator thinks he can do better, so he re-tools the nav plan and makes the nav roll again. But, this time he does even worse. He throws 2D and rolls snake eyes. +2 for skill, and the new Nav roll becomes 4.
Oh crap. This is a tough one. The GM describes the PURSUIT diving into the GG and then getting broadsided by a atmospheric storm. It's a vortex, or a tornado, swirling around at impossible speeds. If the pilot misses his roll, then the GM is determined to make whatever space combat damage that pops up much worse than the first time.
It's a tense situation. The entire ship is rattling. Had there been passengers aboard, the GM might have one of them throw up. At the minimum, a roll on the NPC reaction chart to reflect the passenger's demeanor against the crew would be in order. The PURSUIT's captain, though, was smart. He didn't bring civies with him while skimming. This was strickly a spec trade run.
So, the pilot needs to roll 4- on a throw of 2D -2. He throws, gets a 6 on the roll, and modifies it to a 4.
YEAHH!!!
The entire gaming table explodes. The player playing the pilot is beaming.
The GM describes how, deftly, the pilot rolled the ship, taking the main turblance from the vortex on the aft section of the vessel. Then, he increased the thrust and escaped the vortex, up through its center, before the ship hit the other side.
"Good thing," the GM says, remembering that he was about to let the players have it bad with damage, "that thing was the size of Canada. Your pilot here got you out of it. And now, you've got more fuel in your tanks, but not enough. Care to continue?"
Behind his screen, the GM makes note that 2 of the 5 hours for refueling are completed.
"How full are the tanks?" The player playing the engineer says.
But, the GM, not wanting to tip off the secret time roll, doesn't tell him they're 40% full. He downplays it a bit, to throw the players off."
"You look at the gauge," the GM says to the player, "it reads 18.547% full."
Boosted by the fantastic performance by the ship's pilot, the navigator attempts a third time to alter his course prediction. He makes the Nav roll again. 2D +2. This time, he rolls 8, plus 2, equals 10.
Not a bad roll this time. With the pilot's -2DM, it's as good as one can get. Even if the pilot rolls a 12, his DM will get him under 10.
So, from here on out, the Nav will stick with this plan. It's the best that can be done.
And, all piloting rolls will automatically succeed now, given the Nav's roll.
So, the GM decides to cover the remaining three trips quickly.
"When you dive back down into the gas giant, you see smooth clouds. It's the far side of the storm you hit, and it looks like smooth sailing. Three hours, three dives later, you're done. Full tanks, and one damaged port cargo hatch. It got a little tricky there for a moment, but you made it. You hear a 'moooo' from the cargo deck. Maybe it was one of the cows down there thanking you. Are we moving to jump point now? Or, do you want to go EVA and check out that cargo hatch before the ship jumps...?"
Supplement Four
SOC-14 5K
Playing the heck out of GG Skimming...
If you look at pg. 43 of Sup 5, there's plenty of rules there you can modify for civilan vessels skimming at gas giants.
Pilot skill can come into play as a beneficial DM on some of the throws.
BUT, WHY DON'T YOU TRY THIS...
A rule I've used in my games focuses on the ship's pilot and navigator. Have the Navigator throw 2D and add Nav skill. This represents the navigator's best attempt at giving the pilot a course through the least dangerous areas of the GG's upper atmosphere.
Then, as the ship acutally follows that course in order to skim, have the pilot throw 2D minus Pilot skill, trying to roll the Nav number or less.
If the pilot's roll is less than the Nav number, then the ship made it through the GG's atmo without incident. If the pilot's roll is greater than the Nav number, then roll damage on the ship as if it were hit in space combat (Book 2 damage table). The ship's engineer can effect repairs per normal space combat rules (one roll of 9+ allowed per 15 minutes).
It takes 3D minus pilot skill trips through the GG like this to completely refuel the ship. Each trip takes about an hour to perform. The average time, according to The Traveller Book, to refuel at a GG is 8 hours. The average roll on 3D is 10, and if you subtract the average competent pilot skill of Pilot-2, you get an average of 8 hours using this method.
The navigator can make course adjustments to his initial skimming flight plan each trip, so allow the navigator to re-roll the Nav roll at the completion of one trip. If the Nav roll is high, he'll stick with the original plan and not alter course.
Using this rule, your PCs Navigators and Pilots can take this opportunity to shine.
Engineers, and the rest of the crew, if not fixing turbulance damage, can be busy overseeing the refueling process. GMs may want to get creative with Hull or Cargo Bay damage results from damage, instead describing how the LHyd influx pipe is cracked with all the buffeting, and now liquid hydrogen is filling up engineering compartment C. Or, some such creative problem the players will have to deal with. Maybe an antenna was blown off the hull of the ship, and once the vessel is out of the upper atmosphere of the GG, someone will have to go EVA on the hull to fix it. Or, maybe an intake baffel was damaged, and the engineer has to shut it down. Now, refueling will take twice as long--exposing the ship to more damage.
The GM's imagination is the limit.
On the rolls above, GMs may wish to address character stats. Simply pick a number, in the normal CT way, and say, "If the Navigator has EDU 9+, then he'll add +1 to his Nav roll." Or, maybe "If the Pilot's DEX is 10+, allow a -2DM on the 3D roll that determines the number of trips required to skim a full tank."
Something like that.
BTW, if you're a UGM user, you can easily use the UGM tasks to include stats on these rolls.
Let's look at an example.
Luukhan Pershiire is navigator for the Type A2 Far Trader ADROIT PURSUIT. He's got Navigation-2 and EDU 7. Using the suggested stat DMs above (that I made up on the fly...you may want to put some more thought into them for your game), Luukhan will plot the course the PURSUIT will take through the upper atmosphere of the gas giant filling its bridge port.
He rolls 2D and gets a 4. +2 for skill. The Nav roll becomes 6.
Now, the pilot must dive through the gas giant, using the navigator's plot.
The ship's pilot is Dexter Bryte, Pilot-1. He'll roll 2D -1, attempting to throw 6 or less. This represents about an hour of time in the game as the pilot dives through the gas giant's upper atmo with fuel cocks open.
Dexter throws 8 on the dice, minus 1, which equals 7. Not so good.
The GM then throws on the Book 2 damage table as if the ship had been hit in space combat. The result is hull damage. Being nice, the GM decides that the pressures in the atmo of the gas giant cracked the seal on the port cargo airlock. It's nothing to worry about now, as the inner lock hatch will keep the cargo deck's integrity. But, it will be expensive and.or time consuming to repair. Maybe it's just the seal that needs replacing, and maybe the door has buckled under the strain of ship's maneuvers and high G. The engineer won't know until he can get outside, either by Vacc Suit or while the ship is dirtside, to check it out.
The "cheap" method of skimming fuel for free just became a little more costly than expected.
The GM, giving the PCs a relatively inconsequential problem (they've just got to fix the outer cargo hatch at this point, and that can be done later) has already decided that if another hull result pops up from a failed pilot roll, then the inner lock may go next, exposing the cargo deck to explosive decompression (and now we're talking damage to the cargo as well).
Depending on the player playing the ship's engineer, a GM may want to give the engineer an heads up on this. Maybe the GM will give the engineer a roll to assess the damage.
If he makes it, the engineer may say to the captain, "Cap'n, that's a pretty hard blow she took during that last maneuver. I dunno if the outer hatch will hold. We may want to think about abortin' the skim and headin' back dirtside to buy some fuel."
"That's two days travel and 500 credits a ton, chief. Are you sure?"
"Well, it's your call, Cap'n. But, if we press on, I'd at least want to decompress the hold."
"We've got live cattle down there, chief! We can't do that!"
"Damage 'll be more costly if the inner hatch buckles and we loose the cattle plus other cargo. I say we head dirtside."
"We just don't have the credits, chief. We blew it all on the spec cargo in the hold. We can't even afford 100 credits a ton for the unrefined stuff. The cattle is the least expensive cargo we're carrying. Let's re-tool our flight plan and give 'er another go."
"Your the boss, skip."
So, at this point, the GM determines how many trips it will take the PURSUIT to dive through the gas giant and skim enough fuel to fill the ship's tanks.
Secretly, the GM rolls 3D -2 behind his screen. The -2DM is for Pilot skill. The pilot's EDU is 5, so there's no extra DM bonus there.
The GM makes this roll in secret because, although the navigator can predict how long his flight plan will take to complete, there are several factors in fueling that are unpredictable--density of LHyd being one of them; amount scooped in a trip being another. Turbulance is another factor. So, I suggest making this roll in secret. The navigator's prediction of how long skimming will take is equal to the average of a 3D roll minus pilot skill. The average of 3D is 10. Subtract pilot (Dexter is Pilot-2) and get an average of 8 hours.
So, in secret, the GM makes this roll. He throws 3D and gets 7. Minus 2. It will take 5 trips, at about an hour each, to refuel the PURSUIT.
This is a fairly fortunate roll, but the players really have no idea of their good fortune at this point. It could be 16 hours for all they know.
On trip #2, the ship's navigator thinks he can do better, so he re-tools the nav plan and makes the nav roll again. But, this time he does even worse. He throws 2D and rolls snake eyes. +2 for skill, and the new Nav roll becomes 4.
Oh crap. This is a tough one. The GM describes the PURSUIT diving into the GG and then getting broadsided by a atmospheric storm. It's a vortex, or a tornado, swirling around at impossible speeds. If the pilot misses his roll, then the GM is determined to make whatever space combat damage that pops up much worse than the first time.
It's a tense situation. The entire ship is rattling. Had there been passengers aboard, the GM might have one of them throw up. At the minimum, a roll on the NPC reaction chart to reflect the passenger's demeanor against the crew would be in order. The PURSUIT's captain, though, was smart. He didn't bring civies with him while skimming. This was strickly a spec trade run.
So, the pilot needs to roll 4- on a throw of 2D -2. He throws, gets a 6 on the roll, and modifies it to a 4.
YEAHH!!!
The entire gaming table explodes. The player playing the pilot is beaming.
The GM describes how, deftly, the pilot rolled the ship, taking the main turblance from the vortex on the aft section of the vessel. Then, he increased the thrust and escaped the vortex, up through its center, before the ship hit the other side.
"Good thing," the GM says, remembering that he was about to let the players have it bad with damage, "that thing was the size of Canada. Your pilot here got you out of it. And now, you've got more fuel in your tanks, but not enough. Care to continue?"
Behind his screen, the GM makes note that 2 of the 5 hours for refueling are completed.
"How full are the tanks?" The player playing the engineer says.
But, the GM, not wanting to tip off the secret time roll, doesn't tell him they're 40% full. He downplays it a bit, to throw the players off."
"You look at the gauge," the GM says to the player, "it reads 18.547% full."
Boosted by the fantastic performance by the ship's pilot, the navigator attempts a third time to alter his course prediction. He makes the Nav roll again. 2D +2. This time, he rolls 8, plus 2, equals 10.
Not a bad roll this time. With the pilot's -2DM, it's as good as one can get. Even if the pilot rolls a 12, his DM will get him under 10.
So, from here on out, the Nav will stick with this plan. It's the best that can be done.
And, all piloting rolls will automatically succeed now, given the Nav's roll.
So, the GM decides to cover the remaining three trips quickly.
"When you dive back down into the gas giant, you see smooth clouds. It's the far side of the storm you hit, and it looks like smooth sailing. Three hours, three dives later, you're done. Full tanks, and one damaged port cargo hatch. It got a little tricky there for a moment, but you made it. You hear a 'moooo' from the cargo deck. Maybe it was one of the cows down there thanking you. Are we moving to jump point now? Or, do you want to go EVA and check out that cargo hatch before the ship jumps...?"
If you look at pg. 43 of Sup 5, there's plenty of rules there you can modify for civilan vessels skimming at gas giants.
Pilot skill can come into play as a beneficial DM on some of the throws.
BUT, WHY DON'T YOU TRY THIS...
A rule I've used in my games focuses on the ship's pilot and navigator. Have the Navigator throw 2D and add Nav skill. This represents the navigator's best attempt at giving the pilot a course through the least dangerous areas of the GG's upper atmosphere.
Then, as the ship acutally follows that course in order to skim, have the pilot throw 2D minus Pilot skill, trying to roll the Nav number or less.
If the pilot's roll is less than the Nav number, then the ship made it through the GG's atmo without incident. If the pilot's roll is greater than the Nav number, then roll damage on the ship as if it were hit in space combat (Book 2 damage table). The ship's engineer can effect repairs per normal space combat rules (one roll of 9+ allowed per 15 minutes).
It takes 3D minus pilot skill trips through the GG like this to completely refuel the ship. Each trip takes about an hour to perform. The average time, according to The Traveller Book, to refuel at a GG is 8 hours. The average roll on 3D is 10, and if you subtract the average competent pilot skill of Pilot-2, you get an average of 8 hours using this method.
The navigator can make course adjustments to his initial skimming flight plan each trip, so allow the navigator to re-roll the Nav roll at the completion of one trip. If the Nav roll is high, he'll stick with the original plan and not alter course.
Using this rule, your PCs Navigators and Pilots can take this opportunity to shine.
Engineers, and the rest of the crew, if not fixing turbulance damage, can be busy overseeing the refueling process. GMs may want to get creative with Hull or Cargo Bay damage results from damage, instead describing how the LHyd influx pipe is cracked with all the buffeting, and now liquid hydrogen is filling up engineering compartment C. Or, some such creative problem the players will have to deal with. Maybe an antenna was blown off the hull of the ship, and once the vessel is out of the upper atmosphere of the GG, someone will have to go EVA on the hull to fix it. Or, maybe an intake baffel was damaged, and the engineer has to shut it down. Now, refueling will take twice as long--exposing the ship to more damage.
The GM's imagination is the limit.
On the rolls above, GMs may wish to address character stats. Simply pick a number, in the normal CT way, and say, "If the Navigator has EDU 9+, then he'll add +1 to his Nav roll." Or, maybe "If the Pilot's DEX is 10+, allow a -2DM on the 3D roll that determines the number of trips required to skim a full tank."
Something like that.
BTW, if you're a UGM user, you can easily use the UGM tasks to include stats on these rolls.
Let's look at an example.
Luukhan Pershiire is navigator for the Type A2 Far Trader ADROIT PURSUIT. He's got Navigation-2 and EDU 7. Using the suggested stat DMs above (that I made up on the fly...you may want to put some more thought into them for your game), Luukhan will plot the course the PURSUIT will take through the upper atmosphere of the gas giant filling its bridge port.
He rolls 2D and gets a 4. +2 for skill. The Nav roll becomes 6.
Now, the pilot must dive through the gas giant, using the navigator's plot.
The ship's pilot is Dexter Bryte, Pilot-1. He'll roll 2D -1, attempting to throw 6 or less. This represents about an hour of time in the game as the pilot dives through the gas giant's upper atmo with fuel cocks open.
Dexter throws 8 on the dice, minus 1, which equals 7. Not so good.
The GM then throws on the Book 2 damage table as if the ship had been hit in space combat. The result is hull damage. Being nice, the GM decides that the pressures in the atmo of the gas giant cracked the seal on the port cargo airlock. It's nothing to worry about now, as the inner lock hatch will keep the cargo deck's integrity. But, it will be expensive and.or time consuming to repair. Maybe it's just the seal that needs replacing, and maybe the door has buckled under the strain of ship's maneuvers and high G. The engineer won't know until he can get outside, either by Vacc Suit or while the ship is dirtside, to check it out.
The "cheap" method of skimming fuel for free just became a little more costly than expected.
The GM, giving the PCs a relatively inconsequential problem (they've just got to fix the outer cargo hatch at this point, and that can be done later) has already decided that if another hull result pops up from a failed pilot roll, then the inner lock may go next, exposing the cargo deck to explosive decompression (and now we're talking damage to the cargo as well).
Depending on the player playing the ship's engineer, a GM may want to give the engineer an heads up on this. Maybe the GM will give the engineer a roll to assess the damage.
If he makes it, the engineer may say to the captain, "Cap'n, that's a pretty hard blow she took during that last maneuver. I dunno if the outer hatch will hold. We may want to think about abortin' the skim and headin' back dirtside to buy some fuel."
"That's two days travel and 500 credits a ton, chief. Are you sure?"
"Well, it's your call, Cap'n. But, if we press on, I'd at least want to decompress the hold."
"We've got live cattle down there, chief! We can't do that!"
"Damage 'll be more costly if the inner hatch buckles and we loose the cattle plus other cargo. I say we head dirtside."
"We just don't have the credits, chief. We blew it all on the spec cargo in the hold. We can't even afford 100 credits a ton for the unrefined stuff. The cattle is the least expensive cargo we're carrying. Let's re-tool our flight plan and give 'er another go."
"Your the boss, skip."
So, at this point, the GM determines how many trips it will take the PURSUIT to dive through the gas giant and skim enough fuel to fill the ship's tanks.
Secretly, the GM rolls 3D -2 behind his screen. The -2DM is for Pilot skill. The pilot's EDU is 5, so there's no extra DM bonus there.
The GM makes this roll in secret because, although the navigator can predict how long his flight plan will take to complete, there are several factors in fueling that are unpredictable--density of LHyd being one of them; amount scooped in a trip being another. Turbulance is another factor. So, I suggest making this roll in secret. The navigator's prediction of how long skimming will take is equal to the average of a 3D roll minus pilot skill. The average of 3D is 10. Subtract pilot (Dexter is Pilot-2) and get an average of 8 hours.
So, in secret, the GM makes this roll. He throws 3D and gets 7. Minus 2. It will take 5 trips, at about an hour each, to refuel the PURSUIT.
This is a fairly fortunate roll, but the players really have no idea of their good fortune at this point. It could be 16 hours for all they know.
On trip #2, the ship's navigator thinks he can do better, so he re-tools the nav plan and makes the nav roll again. But, this time he does even worse. He throws 2D and rolls snake eyes. +2 for skill, and the new Nav roll becomes 4.
Oh crap. This is a tough one. The GM describes the PURSUIT diving into the GG and then getting broadsided by a atmospheric storm. It's a vortex, or a tornado, swirling around at impossible speeds. If the pilot misses his roll, then the GM is determined to make whatever space combat damage that pops up much worse than the first time.
It's a tense situation. The entire ship is rattling. Had there been passengers aboard, the GM might have one of them throw up. At the minimum, a roll on the NPC reaction chart to reflect the passenger's demeanor against the crew would be in order. The PURSUIT's captain, though, was smart. He didn't bring civies with him while skimming. This was strickly a spec trade run.
So, the pilot needs to roll 4- on a throw of 2D -2. He throws, gets a 6 on the roll, and modifies it to a 4.
YEAHH!!!
The entire gaming table explodes. The player playing the pilot is beaming.
The GM describes how, deftly, the pilot rolled the ship, taking the main turblance from the vortex on the aft section of the vessel. Then, he increased the thrust and escaped the vortex, up through its center, before the ship hit the other side.
"Good thing," the GM says, remembering that he was about to let the players have it bad with damage, "that thing was the size of Canada. Your pilot here got you out of it. And now, you've got more fuel in your tanks, but not enough. Care to continue?"
Behind his screen, the GM makes note that 2 of the 5 hours for refueling are completed.
"How full are the tanks?" The player playing the engineer says.
But, the GM, not wanting to tip off the secret time roll, doesn't tell him they're 40% full. He downplays it a bit, to throw the players off."
"You look at the gauge," the GM says to the player, "it reads 18.547% full."
Boosted by the fantastic performance by the ship's pilot, the navigator attempts a third time to alter his course prediction. He makes the Nav roll again. 2D +2. This time, he rolls 8, plus 2, equals 10.
Not a bad roll this time. With the pilot's -2DM, it's as good as one can get. Even if the pilot rolls a 12, his DM will get him under 10.
So, from here on out, the Nav will stick with this plan. It's the best that can be done.
And, all piloting rolls will automatically succeed now, given the Nav's roll.
So, the GM decides to cover the remaining three trips quickly.
"When you dive back down into the gas giant, you see smooth clouds. It's the far side of the storm you hit, and it looks like smooth sailing. Three hours, three dives later, you're done. Full tanks, and one damaged port cargo hatch. It got a little tricky there for a moment, but you made it. You hear a 'moooo' from the cargo deck. Maybe it was one of the cows down there thanking you. Are we moving to jump point now? Or, do you want to go EVA and check out that cargo hatch before the ship jumps...?"
Well, not if you're flying what's essentially a huge brick with tailfins, it doesn't.
Most of what makes GG skimming in a Lightning such a festival of dice rolls is the fact the the old girls were specifically not designed for it.
First, they're not technically streamlined as per B2; the "Close Structure" config is going to be a real drag queen [sorry; irresistible pun], and it's not at all surprising that externally-carried craft are likely to get buffeted right out of their moorings.
Secondly, the Lightning class puts all the armor on the outside, carapace-like, and again, money & mass were saved in the design by allowing for "acceptable" leakage in the tanks.
Third, the vulnerability of the m-drive may well be from the aforementioned drag problems. Most GG skimming occurs at around 1/2 an atmo; the turbulence effects are only going to be magnified, and greatly so, by all those flat slabs at oblique angles. The smooth "killer carrots" that form the mainstays of TCS fleets should have a much easier time of it.
In summation, I think the peculiarities of the Lightning class make it an atypical example of how skimming is performed.
Well, I can see the appeal of this whole mechanism; I'm just a little less-inclined to be quite as quick to inflict damage, due to the above considerations. A streamlined, military-drives private vessel should be a little more robust than a Lightning when the wind's a little gusty...
Also note that given the steep gravity wells of most GGs and the short maneuver legs of most private starships, you usually need to be moving at a pretty brisk clip just to maintain altitude -- that's the source of Pilots' turbulence problems: seeing it coming well in advance on LADAR but having too much momentum (and having to maintain too much momentum) to avoid it.
It's the same problem offshore powerboats struggle with: they often have one crewman to steer the boat and a second, dedicated crewman who does nothing but work the throttle in order to keep the engine from over-revving when they crest a wave or the boat then submarining into the face of an oncoming wave. Pilots and Navis could use the same kind of teamwork when skimming to dodge the worst turbulence; Sensor Ops being a must. All in all, it shouldn't be too much worse than what the USAF Hurricane Hunters face when they fly through tropical storms. (Just make sure you use the head before entering the choppy part of the trip. And maybe skip breakfast.)
I'd say the primary argument against routine GG skimming by civvies is that at 1 or 2Gs, unless the mainworld is one of its moons, it takes for frakkin' ever to get all the way out there... and time is money, even at Cr100/dton savings...
Well, not if you're flying what's essentially a huge brick with tailfins, it doesn't.
Most of what makes GG skimming in a Lightning such a festival of dice rolls is the fact the the old girls were specifically not designed for it.
First, they're not technically streamlined as per B2; the "Close Structure" config is going to be a real drag queen [sorry; irresistible pun], and it's not at all surprising that externally-carried craft are likely to get buffeted right out of their moorings.
Secondly, the Lightning class puts all the armor on the outside, carapace-like, and again, money & mass were saved in the design by allowing for "acceptable" leakage in the tanks.
Third, the vulnerability of the m-drive may well be from the aforementioned drag problems. Most GG skimming occurs at around 1/2 an atmo; the turbulence effects are only going to be magnified, and greatly so, by all those flat slabs at oblique angles. The smooth "killer carrots" that form the mainstays of TCS fleets should have a much easier time of it.
In summation, I think the peculiarities of the Lightning class make it an atypical example of how skimming is performed.
Well, I can see the appeal of this whole mechanism; I'm just a little less-inclined to be quite as quick to inflict damage, due to the above considerations. A streamlined, military-drives private vessel should be a little more robust than a Lightning when the wind's a little gusty...
Also note that given the steep gravity wells of most GGs and the short maneuver legs of most private starships, you usually need to be moving at a pretty brisk clip just to maintain altitude -- that's the source of Pilots' turbulence problems: seeing it coming well in advance on LADAR but having too much momentum (and having to maintain too much momentum) to avoid it.
It's the same problem offshore powerboats struggle with: they often have one crewman to steer the boat and a second, dedicated crewman who does nothing but work the throttle in order to keep the engine from over-revving when they crest a wave or the boat then submarining into the face of an oncoming wave. Pilots and Navis could use the same kind of teamwork when skimming to dodge the worst turbulence; Sensor Ops being a must. All in all, it shouldn't be too much worse than what the USAF Hurricane Hunters face when they fly through tropical storms. (Just make sure you use the head before entering the choppy part of the trip. And maybe skip breakfast.)
I'd say the primary argument against routine GG skimming by civvies is that at 1 or 2Gs, unless the mainworld is one of its moons, it takes for frakkin' ever to get all the way out there... and time is money, even at Cr100/dton savings...
The ultimate "unprofitability" of skimming gas giants is the typical 7 day trip from the main world to the Gas Giant that reduces a marginally profitable trader from 1 week in jump/1 week on planet/jump again to 1 week in jump/1 week on planet/1 week traveling to GG/jump again. The reduction from 25 paying jumps per year to 16 paying jumps per year will cost far more than the cost of the fuel.
Supplement Four
SOC-14 5K
I'd agree with that. The AHL text alludes to that as well.
No prob. Stick a well-trained pilot and nav in there, and modify the dice rolls in their favor.
Maybe the pirate vessel you mention, like the fuel skimmers for the Lightning Class, is designed to be used in GG atmo.
If so, add some DMs to the die rolls I mention above (when and only when you want to play out the refueling procedure. I certainly wouldn't do all this if it weren't fun. If the story doesn't call for it, then skip over the skim, as they say.)
Maybe you'd modify the Nav roll so that it's easier for the pilot.
For example, let's say you've got a navigator with Navigation-2. And, let's say the ship is built for GG stresses, like the fuel skimmers for the Lightning Class. Add another +2DM in there for the ship's performance in such an environment.
If you do that, any roll above an 8 (roll of 9-12) or better will result in the pilot making the skim dive 100% of the time.
And, if you've got a good pilot, this will even be lower. If you've got a Pilot-2, with the nav DMs above, the skim roll becomes even easier.
For example:
Nav-2, Ship DM of +2
---------------------
2D roll totals 6 +4 = 10
With a Pilot-2, the skim will always succeed without damage on a roll of 6+.
Because, say the pilot's roll is 12 -2 = 10. He succeeds.
Acutally, the GGs are so large, that upper atmo gravity isn't so bad. It drops off fairly steeply. It's the gravity deep into the atmo that has the high G rating.
True. Especially if you use the House Rule that states the ship's M-Drive rates both the inertial compensation of the vessel and the thrust.
Thus, if a ship has a 3G drive, 2Gs can be spent on thrust, while 1G maintains the 1G deck field. If the ship goes to "emergency maneuvers", using all 3Gs for thrust, the ship's passengers are suffering from 3G acceleration. Acceleration couches and maybe pressure/vacc suits are necessary, or they take damage.
Supplement Four
SOC-14 5K
I'd agree with that. The AHL text alludes to that as well.
No prob. Stick a well-trained pilot and nav in there, and modify the dice rolls in their favor.
Maybe the pirate vessel you mention, like the fuel skimmers for the Lightning Class, is designed to be used in GG atmo.
If so, add some DMs to the die rolls I mention above (when and only when you want to play out the refueling procedure. I certainly wouldn't do all this if it weren't fun. If the story doesn't call for it, then skip over the skim, as they say.)
Maybe you'd modify the Nav roll so that it's easier for the pilot.
For example, let's say you've got a navigator with Navigation-2. And, let's say the ship is built for GG stresses, like the fuel skimmers for the Lightning Class. Add another +2DM in there for the ship's performance in such an environment.
If you do that, any roll above an 8 (roll of 9-12) or better will result in the pilot making the skim dive 100% of the time.
And, if you've got a good pilot, this will even be lower. If you've got a Pilot-2, with the nav DMs above, the skim roll becomes even easier.
For example:
Nav-2, Ship DM of +2
---------------------
2D roll totals 6 +4 = 10
With a Pilot-2, the skim will always succeed without damage on a roll of 6+.
Because, say the pilot's roll is 12 -2 = 10. He succeeds.
Acutally, the GGs are so large, that upper atmo gravity isn't so bad. It drops off fairly steeply. It's the gravity deep into the atmo that has the high G rating.
True. Especially if you use the House Rule that states the ship's M-Drive rates both the inertial compensation of the vessel and the thrust.
Thus, if a ship has a 3G drive, 2Gs can be spent on thrust, while 1G maintains the 1G deck field. If the ship goes to "emergency maneuvers", using all 3Gs for thrust, the ship's passengers are suffering from 3G acceleration. Acceleration couches and maybe pressure/vacc suits are necessary, or they take damage.
Supplement Four
SOC-14 5K
You've touched on something here that I haven't been thinking about until I wrote an entry in the Rules Index thread.
And that is the CT Escape Velocity Rule.
-------------------------------------------------
(From the Index Thread)
I'll also note an Official Classic Traveller rule that many people do not know or observe (probably because the rule gets murky in other Traveller editions). And, that rule is that if a ship's M-Drive rating is less than the G field of a world, then that ship cannot land on the world (because it won't be able to make escape velocity to leave the world again).
This is only a problem with ships that have 1G M-Drives. Those ships cannot, in CT canon, land on worlds of size 8+. They need to dock at high ports and use shuttles or ship's vehicles to reach dirtside.
Again, this rule is basically forgotten about in later editions of Traveller, so you might want to ignore it too. But, I think it's a fun rule that adds a lot of detail to the Traveller universe. I use it in my game.
When vessels do land on worlds, they use some part of thier drives to remain afloat, with the rest of the drive directed towards thurst. This means a ship with a 1G drive doesn't make escape velocity as if it had 1G of thrust. Look at the table on pg. 37 of Book 2. Subtract the world's G field from your ship's G rating. That will give you how much thrust your ship can produce on any given size world.
For example, if a ship with a 1G drive lands on a Size 7 world, the ship will move as if it's drive were rated at 0.125 Gs. You should use that whenever using the Travel Formula when inside the world's gravitational field.
-------------------------------------------------
Now, in real life, a gas giant's gravity field drops pretty quickly as an object reaches the upper atmosphere of the GG. NASA has sent probes extremely close to the upper atmosphere of our own system's GGs, and they don't have anything close to a 1G M-Drive on them.
But, CT, for necessary game reasons, tends to color over some real world details. And, if you check the chart on pg. 37 of Book 2, you'll see some high-G ratings from GGs. Those G ratings are probably pretty accurate for the GG's deep atmosphere, but they're not accurate for the upper atmosphere where skimming will be done.
A GM could rule, though, that skimming can't be done at the upper atmosphere level--that the captured hydrogen is not dense enough...that it would take so many hours/days that it wouldn't be worth the effort.
In order to skim, a ship must dive deeper into the GG's atmo, where the atmo is more dense, in order to scoop hydrogen.
Given this rule, it makes perfect sense that civilian vessels don't have fuel perification plants. The reason is that most of them aren't capable of escape velocity from deep atmo runs through a GG.
2G drives would be required for GG skimming on small GGs. 3G drives would be required for GG skimming on large GGs.
Most civilian craft have 1G or 2G drives. And thus, at least for ships with 1G drives, skimming would be impossible. And, if the GG is large, skimming is impossible for ships with 2G drives.
Use this, in combination with my skimming rules I posted above, and skimming is possible in a game, but a ship with a 2-3G drive is needed, a good navigator, and a capable pilot.
The 2G vessel with the Navigator-0 and the Pilot-1 might be in trouble if it tries to skim at a small GG.
Makes sense to me.
Supplement Four
SOC-14 5K
You've touched on something here that I haven't been thinking about until I wrote an entry in the Rules Index thread.
And that is the CT Escape Velocity Rule.
-------------------------------------------------
(From the Index Thread)
I'll also note an Official Classic Traveller rule that many people do not know or observe (probably because the rule gets murky in other Traveller editions). And, that rule is that if a ship's M-Drive rating is less than the G field of a world, then that ship cannot land on the world (because it won't be able to make escape velocity to leave the world again).
This is only a problem with ships that have 1G M-Drives. Those ships cannot, in CT canon, land on worlds of size 8+. They need to dock at high ports and use shuttles or ship's vehicles to reach dirtside.
Again, this rule is basically forgotten about in later editions of Traveller, so you might want to ignore it too. But, I think it's a fun rule that adds a lot of detail to the Traveller universe. I use it in my game.
When vessels do land on worlds, they use some part of thier drives to remain afloat, with the rest of the drive directed towards thurst. This means a ship with a 1G drive doesn't make escape velocity as if it had 1G of thrust. Look at the table on pg. 37 of Book 2. Subtract the world's G field from your ship's G rating. That will give you how much thrust your ship can produce on any given size world.
For example, if a ship with a 1G drive lands on a Size 7 world, the ship will move as if it's drive were rated at 0.125 Gs. You should use that whenever using the Travel Formula when inside the world's gravitational field.
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Now, in real life, a gas giant's gravity field drops pretty quickly as an object reaches the upper atmosphere of the GG. NASA has sent probes extremely close to the upper atmosphere of our own system's GGs, and they don't have anything close to a 1G M-Drive on them.
But, CT, for necessary game reasons, tends to color over some real world details. And, if you check the chart on pg. 37 of Book 2, you'll see some high-G ratings from GGs. Those G ratings are probably pretty accurate for the GG's deep atmosphere, but they're not accurate for the upper atmosphere where skimming will be done.
A GM could rule, though, that skimming can't be done at the upper atmosphere level--that the captured hydrogen is not dense enough...that it would take so many hours/days that it wouldn't be worth the effort.
In order to skim, a ship must dive deeper into the GG's atmo, where the atmo is more dense, in order to scoop hydrogen.
Given this rule, it makes perfect sense that civilian vessels don't have fuel perification plants. The reason is that most of them aren't capable of escape velocity from deep atmo runs through a GG.
2G drives would be required for GG skimming on small GGs. 3G drives would be required for GG skimming on large GGs.
Most civilian craft have 1G or 2G drives. And thus, at least for ships with 1G drives, skimming would be impossible. And, if the GG is large, skimming is impossible for ships with 2G drives.
Use this, in combination with my skimming rules I posted above, and skimming is possible in a game, but a ship with a 2-3G drive is needed, a good navigator, and a capable pilot.
The 2G vessel with the Navigator-0 and the Pilot-1 might be in trouble if it tries to skim at a small GG.
Makes sense to me.
Straybow
SOC-14 1K
Skimming a GG doesn't require thrust equal to gravity. An aerodynamic hull could skim without any thrust at all, although it would be a jarring ride.
Grav "thrusters" don't create a force acting on the ship, they accelerate the entire volume of space occupied by the ship. I-comp is only there to protect the contents against impacts and the like.
Turbulant buffeting peaks in an atmosphere can easily exceed 6G. Impacts or explosions generate spikes measured in tens of Gs. Therefore, I-comp goes by slightly different rules based on average power consumption (and suitable handwaving).
Grav "thrusters" don't create a force acting on the ship, they accelerate the entire volume of space occupied by the ship. I-comp is only there to protect the contents against impacts and the like.
Turbulant buffeting peaks in an atmosphere can easily exceed 6G. Impacts or explosions generate spikes measured in tens of Gs. Therefore, I-comp goes by slightly different rules based on average power consumption (and suitable handwaving).
FWIW, IMTU all spacecraft grav drives can operate in two modes: the normal "direct thrust" mode, used for getting around in the conventional manner and which includes integral accel comp by default (as part of the field effect) on ships with computer-controlled m-drives (which means not small craft); as well as "contragravity" mode, which is more fuel-efficient, can only be used to "push" against local gravity up to 2Gs, and results in a performance envelope like that of an air/raft -- world size in hours to orbit/deorbit.
This makes that lingering rules oversight go away with minimal hand-waving.
Not necessarily; you can skim up where the air is rare (and the hydrogen is actually a higher percentage of what you encounter), if you just go fast enough.
A grav-propelled vessel's maximum effective ground speed is a function of atmo drag; less atmo, higher top speed in atmo. 1G is plenty to skim with; you just have to stay high and fast.
FWIW, IMTU all spacecraft grav drives can operate in two modes: the normal "direct thrust" mode, used for getting around in the conventional manner and which includes integral accel comp by default (as part of the field effect) on ships with computer-controlled m-drives (which means not small craft); as well as "contragravity" mode, which is more fuel-efficient, can only be used to "push" against local gravity up to 2Gs, and results in a performance envelope like that of an air/raft -- world size in hours to orbit/deorbit.
This makes that lingering rules oversight go away with minimal hand-waving.
Not necessarily; you can skim up where the air is rare (and the hydrogen is actually a higher percentage of what you encounter), if you just go fast enough.
A grav-propelled vessel's maximum effective ground speed is a function of atmo drag; less atmo, higher top speed in atmo. 1G is plenty to skim with; you just have to stay high and fast.
Yes, but -- it's a drag issue. In order to ram that very, very thin atmo into the scoops (and presumed compressors) with enough flow to fill your tanks at any sort of time-efficient rate whilst staying above the soup, you need to be moving fast enough to generate a fair amount of pressure-driven inflow, and thus drag.
Otherwise you're just aerobraking, and that will be unhealthy for maintaining your altitude and escape velocity... especially for the extended length of time required to then tank up on mere wisps and puffs...
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