Alternity --> T20 conversions
- Thread starter Mr. Oberon
- Start date
Once you add intterstellar hydrogen which acts as a "brake" when travelling fast, you can easily have speed limits which give you "cruising" and "Maneuvering" speeds - ie the speed at which the acceleration from the drive balances the decelleration from friction.
Having said that
Pre Note: I have never read alternatively so I don;t really know the concepts here however the last comment gave me an immediate Knee jerk reaction.
2,700G shouldn;t affect the structure of the ship - As long as it's evenly applied. If you have a drive that accelerates the ship in toto rather than accelerates itself and relies on the ship being welded onto it, then the problems of requiring a ship made from exotic matter doesn;t apply (Which it would if you were required to survive a 27,000G acceleration)
Of course, the power output required to generate that sort of delta V are fairly impressive. Assume a 1000 mass ton ship which is being accelerated at 270,000m/s/s - roughly 300 million ton m/sec squared - Translating from that into normal units (1 ton -> 1000kng?) I get
3 * 10 ^ 11 Newtons. If the candidate ship is accelerating for 1AU then it would require a total energy output of roughly 4*10^22Joules over an hour (54 minutes) which is roughly 2*10^20 Watts
Translating from that into english that is 2 hundred millilon Terawatts!!!!
It's been many years since I did any physics and so I've probably made some mistakes -
The amount of energy that would have to be annialated to yield 4*10^22 Joules seems to be in the order of 5*10^5 kg - I'm on much shakier ground here - can someone else say how much matter would yield 4*10^22 Joules?
However it works out, that's a rip roaring drive.
Paul
Mr. Oberon
SOC-11
Dark Matter Reactors are Gooooood! 
Assume that somehow Dark Matter can yield 10 times the energy that normal matter does, this would still take 10^4 kg of matter - ie 10 tons that is used up as fuel.
If you need that sort of energy rate and are happy with hand waving, tapping the quantum foam seems to be a much safer way to go about it. ie you get energy from nothing, no matter used up in the process - It's all good.
Rereading your first post. Does Dark matter generate "normal" matter that is then used up in the process - ie Dark matter is a catalyst that drags matter and antimatter into being in a continual process.
Effectivly Dark matter is something that interupts the quantum process of continual matter creation/destruction. You still get energy from nothing, but the hand waving is a lot less. It also indicates that containment problems with the reactor are likely to be spectacular (remember it is generating roughly 100kg of antimatter per minute)
If you need that sort of energy rate and are happy with hand waving, tapping the quantum foam seems to be a much safer way to go about it. ie you get energy from nothing, no matter used up in the process - It's all good.
Rereading your first post. Does Dark matter generate "normal" matter that is then used up in the process - ie Dark matter is a catalyst that drags matter and antimatter into being in a continual process.
Effectivly Dark matter is something that interupts the quantum process of continual matter creation/destruction. You still get energy from nothing, but the hand waving is a lot less. It also indicates that containment problems with the reactor are likely to be spectacular (remember it is generating roughly 100kg of antimatter per minute)
True, sort of. But then your crusing speed becomed dependent upon the density of inter{planetary|stellar} space.
Which implies the star trek warp field rather than any sort of reaction drive.
I get 444 tons. See E=mc^2 so m = E/c^2...
And that's assuming perfect conversion.
You are joking right? Please tell me you do not actually think we can map the inside of a starship orbiting Mars from earth using a gravametric scanner...
</font>[/QUOTE]We do, in fact, have mass detectors. Dr. Robert Forward designed a series of them in reality as well as fiction. They are no where near as sophistocated as your comment would suggest. Forward's device is extremely sensitive but can pretty much only measure mass and direction.There is also a project underway at various labs around the world to accurately measure the Gravitational constant of the universe. (Apparently it needs to be updated.) The principle device in use bears much resemblence to the one designed by Dr. Forward.
The following citations can be found on Dr. Forward's home page:
"Detectors for Dynamic Gravitational Fields", Ph.D. Thesis, University of Maryland, College Park, Maryland (June 1965).
"Mass Detection by Means of Measuring Gravity Gradients", with C.C. Bell and J.R. Morris, Paper AIAA-65-403, AIAA Second Annual Meeting, San Francisco, California (26-29 July 1965).
And a paper on one of his designs can be found at:
http://www.whidbey.com/forward/pdf/tp021.pdf
Your mileage may vary.
Mr. Oberon
SOC-11
I will take your word for it. Sorry tjoneslo, guess I was wrong.
No problem, Gearheading my business, and business is good.
While the modern day sensors could'nt map the interior of the ship around Mars, given the enormous gravitational energy being generated, detecting it should be a trivial matter.
While the modern day sensors could'nt map the interior of the ship around Mars, given the enormous gravitational energy being generated, detecting it should be a trivial matter.
So why DOES Traveller have such small and pathetic accelerations? I'm fully expecting a very gearheady answer to that question, and that's fine.
I mean, if Traveller really uses a standard 1-G drive, won't it take a long time to get anywhere in a star system? Like, a really, really long time?
Also, is it possibly because Traveller doesn't assume the existence of automagical "compensators" that take all that acceleration and convert it into a nice steady 1-G gravity field for all the people on the ship? Or does it?
I'm confused.
I mean, if Traveller really uses a standard 1-G drive, won't it take a long time to get anywhere in a star system? Like, a really, really long time?
Also, is it possibly because Traveller doesn't assume the existence of automagical "compensators" that take all that acceleration and convert it into a nice steady 1-G gravity field for all the people on the ship? Or does it?
I'm confused.
Pathetic compared to what? The best space drives we can come up with can manage only a few hundreths of a G, or slightly more than 2G for a few minutes.
The timescale of an interplanetary journey at 1-3G is days to months depending upon distance. Compared to minutes to days for the Alternity drives. Depends upon your style of play. Traveller always had a languid pace, a couple of weeks to shoot out to the jump limit, a week in jump, another to make planetfall at the destination. Alternity liked the idea of a few minutes to the jump point, microsecond jump then another few minutes to planetfall.
For a gearheading answer: the power requirements for a 2,700G drive is absurdly huge compared to the 2G drive, requiring massive handwave powerplans in addition to the massive handwave drive system. And unless the GM and/or players can't handle the "OK, you get there, it's two weeks later", there really isn't any difference between them.
The timescale of an interplanetary journey at 1-3G is days to months depending upon distance. Compared to minutes to days for the Alternity drives. Depends upon your style of play. Traveller always had a languid pace, a couple of weeks to shoot out to the jump limit, a week in jump, another to make planetfall at the destination. Alternity liked the idea of a few minutes to the jump point, microsecond jump then another few minutes to planetfall.
For a gearheading answer: the power requirements for a 2,700G drive is absurdly huge compared to the 2G drive, requiring massive handwave powerplans in addition to the massive handwave drive system. And unless the GM and/or players can't handle the "OK, you get there, it's two weeks later", there really isn't any difference between them.
I disagree a bit with the premise of the comment. I think that you can extrapolate out a basic formla to determine what thrust a set engine type will generate.
I had always considered that there was a 6G limit becuase of the limit of the grav plates in dampening the inerta of the thrust forces.
Following that rule there's no reason to have a 6G limit on missile.
I'd like to see a set of design rules for missiles and torpedoes.........
I had always considered that there was a 6G limit becuase of the limit of the grav plates in dampening the inerta of the thrust forces.
Following that rule there's no reason to have a 6G limit on missile.
I'd like to see a set of design rules for missiles and torpedoes.........
I know real-life space drives are REALLY slow, I'm just curious why most "new" science-fiction has such more powerful drives. I guess it's because people are too impatient to imagine their characters waiting around for 3 weeks just to get anywhere. Heh. ..by the way, the "microsecond" jumps of Alternity (at least for Star*Drive) are actually 121 minutes. That's a little over 5 days, which puts it pretty close to Traveller jumpdrives.
However, yes, they do have MUCH faster accels.
However, yes, they do have MUCH faster accels.
Back in the CT days I had missile rules for building missiles as well. Following the 6G grav field restriction we had enigne units to generate really fast missiles; all for space trade-off. Also did torpedoes...basically a torp launcher took an entire hardpoint (a torp was 3xmissile all in one package.
Question...
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