Fritz_Brown
Super Moderator
Well, usually, running into a gravity well hurts. (It's not the fall that kills ya, it's the sudden stop at the end....)
JUMP - bearing and speed
- Thread starter atpollard
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TheEngineer
SOC-14 1K
I mean, is there some rulewise note, that it hurts ?
I don't know such a thing ... perhaps somebody else does ...?
E.g. in MT the typical procedures simply assume, that the ship pops out at the 100D limit
And even CT wise the holy jumpspace article states:
I don't know corresponding TNE or GURPS stuff ...
So IMTU (MT) navigation always leads to the 100D limit and forced pop out feels a bit like mildy rough landing with an airplane...
regards,
TE
I don't know such a thing ... perhaps somebody else does ...?
E.g. in MT the typical procedures simply assume, that the ship pops out at the 100D limit
And even CT wise the holy jumpspace article states:
I don't know corresponding TNE or GURPS stuff ...
So IMTU (MT) navigation always leads to the 100D limit and forced pop out feels a bit like mildy rough landing with an airplane...
regards,
TE
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Andrew Boulton
The Adminator
BetterThanLife
SOC-14 1K
Don't take gravity lightly, or it will get you down.
Lithobraking
That's where those black globes become handy. Given enough capacitors and a regenerative system to store the energy for later use, you land the ship creating your own fused rock landing pad and use the absorbed kinetic energy to refuel the ship at the same time.
I recommend a heavily armed merchant though, this technique seems to annoy the locals (and the owner of any ship that WAS parked where you just landed).
I use the randomly variable jump times and even positions to come into play...bad navigators suffer more from it than expert ones....an uncertain task
I also allow keeping the vector through jump...but for the above reasons and the possible dangers, most big commercial ships and non-vital military go to "zero vector" before jump for safety. Foolhardy folks and emergencies are places for big vectors at jump entry
I also allow keeping the vector through jump...but for the above reasons and the possible dangers, most big commercial ships and non-vital military go to "zero vector" before jump for safety. Foolhardy folks and emergencies are places for big vectors at jump entry
Seems to me to be fairly "straightforward".
In theory an updated nav computer with reasonably recent starcharts will know what the correction vector would be between any two charted systems.
That is, if I'm in System A and have a zero vector, relative to System A, and I want to go in to System B, and have a zero vector there as well, I would need to put the ship on a compensating negative vector prior to jump. When I arrive from jump in the new system, I will have an effectively zero vector relative to System B.
Those correction vectors should be fairly constant and stay stable over time, particularly any reasonably short time (10's-100's of years).
Also, you should be able to calculate a rough vector solely through observation from the two systems.
Of course, there's no reason to have to correct the vector in the original system, you can simply compensate once you get there.
Assuming the link provided earlier about "Space Velocity" is accurate (in that most systems travel 20-100 km/s), then even a TNE ship should have no problem making the proper correction. In theory, the largest vector you'd have to compensate for is 200 km/s (100 km/s in each system, but pointing in an opposite direction). At 1G burn rate, you can reach 200 km/s in less than 6hrs of solid burn time. And most ships come with 40+ hrs of fuel (24 for the Far Trader, 16 for the Yacht in the TNE book).
Obviously, if you need to have fuel to compensate for system differentials, you won't create a ship that can't do it.
But if the problem is "I am stopped at coord X, Y, Z at vector 0 in System A, and I want to be at location X', Y', Z' at vector 0 in System B", then you need to know how long the jump takes, because since everything is moving, and if a Jump takes 168hr, then Planet Q of System B is going to move over the 7 days of travel, plus the basic motion of the actual star system (~12M km over 7 days).
I've always assumed that the J Drive will plop my fanny at point X, Y, Z assuming it's a safe jump (not within 100D, etc.). So the game is calculating the correct X, Y, Z, timing the jump (since we're hitting a moving target), and then lighting the engines either pre- or post-jump to compensate for the new arrival location and vector.
And that's what the astro nav computer is for. It lets me point and click my way to glory. Click on System A, click on System B, tell it "closest approach vector for 3rd Planet High Port", hit the GO button, and out comes a slew of jump sequences, nav coordinates, gimble marks and burn times. Which, conveniently, the flight computer can handle.
In theory an updated nav computer with reasonably recent starcharts will know what the correction vector would be between any two charted systems.
That is, if I'm in System A and have a zero vector, relative to System A, and I want to go in to System B, and have a zero vector there as well, I would need to put the ship on a compensating negative vector prior to jump. When I arrive from jump in the new system, I will have an effectively zero vector relative to System B.
Those correction vectors should be fairly constant and stay stable over time, particularly any reasonably short time (10's-100's of years).
Also, you should be able to calculate a rough vector solely through observation from the two systems.
Of course, there's no reason to have to correct the vector in the original system, you can simply compensate once you get there.
Assuming the link provided earlier about "Space Velocity" is accurate (in that most systems travel 20-100 km/s), then even a TNE ship should have no problem making the proper correction. In theory, the largest vector you'd have to compensate for is 200 km/s (100 km/s in each system, but pointing in an opposite direction). At 1G burn rate, you can reach 200 km/s in less than 6hrs of solid burn time. And most ships come with 40+ hrs of fuel (24 for the Far Trader, 16 for the Yacht in the TNE book).
Obviously, if you need to have fuel to compensate for system differentials, you won't create a ship that can't do it.
But if the problem is "I am stopped at coord X, Y, Z at vector 0 in System A, and I want to be at location X', Y', Z' at vector 0 in System B", then you need to know how long the jump takes, because since everything is moving, and if a Jump takes 168hr, then Planet Q of System B is going to move over the 7 days of travel, plus the basic motion of the actual star system (~12M km over 7 days).
I've always assumed that the J Drive will plop my fanny at point X, Y, Z assuming it's a safe jump (not within 100D, etc.). So the game is calculating the correct X, Y, Z, timing the jump (since we're hitting a moving target), and then lighting the engines either pre- or post-jump to compensate for the new arrival location and vector.
And that's what the astro nav computer is for. It lets me point and click my way to glory. Click on System A, click on System B, tell it "closest approach vector for 3rd Planet High Port", hit the GO button, and out comes a slew of jump sequences, nav coordinates, gimble marks and burn times. Which, conveniently, the flight computer can handle.
Icosahedron
SOC-14 1K
Ah, Whartung, a voice of reason.
And of course, all of this needn't be calculated out, it can just be added in as role-playing chrome by the navigator if he or she wants to, simply rolling a couple of dice for the appropriate vector - made up on the fly in glorious CT fashion.
And of course, all of this needn't be calculated out, it can just be added in as role-playing chrome by the navigator if he or she wants to, simply rolling a couple of dice for the appropriate vector - made up on the fly in glorious CT fashion.
Icosahedron
SOC-14 1K
That's where those black globes become handy. Given enough capacitors and a regenerative system to store the energy for later use, you land the ship creating your own fused rock landing pad and use the absorbed kinetic energy to refuel the ship at the same time.
Hmm, not so sure about this, ATP, you're going to need an awful lot of capacitors to perform 'lithobraking'. (Yes, I know the whole idea is tongue-in-cheek.)
Book 5 tells us that 1dT of capacitors will hold 36EP, at 250MW per EP - that's 9GW/dT.
But 5 also tells us that a globe absorbs *all* energy; I took that as including the kinetic energy of the atmosphere's atoms, and if you add that in to the power needed to create a 'fused rock landing pad' *and* take the whole site down to absolute zero, I imagine you're not going to have much cargo space left around your capacitors - though I have no intention of doing the calculations!
I've had a 'snowstorm' effect occur when a globed ship has accidentally brushed the atmosphere, and diced for the percentage of capacitor volume suddenly filled by the error (20-120%) :toast:
Fritz_Brown
Super Moderator
Hah! :file_21: :toast:Lithobraking
Fritz_Brown
Super Moderator
Whartung, you left out only one bit - the motion of all the other planets/ bodies in the system. In the single-world dwarf-star systems - not a problem. In the giant systems, with 14 orbits, plus three captured planets (with moons, no less!), and some more planets orbiting the second sun - a little bigger math problem. Which is why its a good idea to buy those jump tapes.... 
(Or jump in out of the ecliptic!
)
(Or jump in out of the ecliptic!
)
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TheEngineer
SOC-14 1K
Yep, might take a few ms more
Whartung, you left out only one bit - the motion of all the other planets/ bodies in the system. In the single-world dwarf-star systems - not a problem. In the giant systems, with 14 orbits, plus three captured planets (with moons, no less!), and some more planets orbiting the second sun - a little bigger math problem. Which is why its a good idea to buy those jump tapes....
(Or jump in out of the ecliptic!
Just to be pedantic...
As for the 14 orbits and 3 captured planets, plus comets, asteroids, Empress Waves, etc. yada etc., I would like to hope that there's enough of a gap between, oh, Earth and Mars (or, say, the Moon) for my ship to sneak in with some room for margin of error.
Also, Earth travels at ~31 km/s. At 100 Diameters, a badly placed ship has ~12 hrs to "get out of the way". Takes about 45min to accelerate to 31 km/s at 1G. Looks like lots of room to me.
And whether you come rushing it on a hot vector and hit a big rock or pop in with a null vector only to be hit by a big rock on a hot vector, consequences about the same I'd think. It's allll relative.
BetterThanLife
SOC-14 1K
Space is a pretty empty and desolate place. However like I said earlier you are headed to one of the busy places in space. Lets say you can get out of the way of the planet. No big deal. You can get out of the way of a moon. But what happens if you happen to come out in a lunar orbit (Obviously a distant orbit compared to our moon.) 45 degrees in front of the moon. (45 degrees behind the moon would be equally bad.) You can get out of the way of the moon, you have time except that you came out in one of the two stable Lagrange Points. And that is a very busy point in space. You better have some serious armor to survive passing through L4 or L5 for that moon. (Those points happen to collect all the trash in or near lunar orbit.) There is a similar point in front and behind all worlds as they orbit the sun. At even a sedate 31km/hr you won't have time to get out of the way now. (And you thought Hail was bad.) If you happen to come in outside that, you have to add to your trip to go around those points or the moon. All of this makes the +/-16.8 hours a royal pain if not outright hazardous.
Icosahedron
SOC-14 1K
And the chances of jumping into a Lagrange point by accident are...?
As you said, BTL, space is very very empty, even in the region of a busy Starport. Personally, I don't think jump tolerances or navigational errors are likely to be much of a problem on their own. The thing that will put you in the path of something dangerous is an evil Referee, not the maths.
As you said, BTL, space is very very empty, even in the region of a busy Starport. Personally, I don't think jump tolerances or navigational errors are likely to be much of a problem on their own. The thing that will put you in the path of something dangerous is an evil Referee, not the maths.
BetterThanLife
SOC-14 1K
Overall streets are pretty empty as well. But jumping into the heart of some systems would be like trying to land a Gulfstream on the streets of Midtown Manhattan during rush hour wearing a blindfold.
The cars in Manhattan are bumper to bumper most of the day, so you just need good shock absorbers to compensate for the bumpy "runway".
The blindfold is more of a problem.
BetterThanLife
SOC-14 1K
The cars in Manhattan are bumper to bumper most of the day, so you just need good shock absorbers to compensate for the bumpy "runway".
The blindfold is more of a problem.
ROFLMAO! I think there might be an issue if you put down on a group of taxicabs and ran into the back of an SUV, van or truck.
ROFLMAO! I think there might be an issue if you put down on a group of taxicabs and ran into the back of an SUV, van or truck.
How hard would it be to trick out an airplane with monster truck tires to compensate for the "SUV factor"?
BetterThanLife
SOC-14 1K
ROFLMAO (Again.)!
There is the small factor of maintaining aerodynamic stability and flight capability which is likely to preclude the need to land in the first place.
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