AnotherDilbert
SOC-14 1K
It's a funny kind of reaction drive that use no reaction mass...
Your choice, of course.
Manoeuvre drive placement...?!
- Thread starter Redcap
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Timerover51
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For the maneuver drive, I use the Dean Drive, which converts rotary acceleration into thrust, without reaction mass. If I do not want to turn the ship around when braking is needed, I mount the drives on the side of the ship, similar to the placement of the jet engines on the Comet jetliner. Scaled down versions are used to supply the drive on contra-gravity vehicles. I suspect that is what H. Beam Piper was thinking of with respect to his Abbott drives, which did not use reaction mass.
You could use fusion reaction drives, as if I remember correctly, Maxwell Hunter in Thrust Into Space gives them a specific impulse of between 3 and 4 Million. As you would be using reaction mass though, you might not necessarily want to continuously boost during planetary departure and arrival. Also, unless you have forward facing fusion nozzles, you are going to have to turn the ship around to brake it. You would also want to make very sure that the exhaust from the fusion jet downs not intersect anything.
Edit Note: The other advantage of the Dean/Abbott Drive is that I can use it as a maneuver drive in the atmosphere for streamlined ships with no problems. You are going to have problems with a fusion reaction drive in the atmosphere.
You could use fusion reaction drives, as if I remember correctly, Maxwell Hunter in Thrust Into Space gives them a specific impulse of between 3 and 4 Million. As you would be using reaction mass though, you might not necessarily want to continuously boost during planetary departure and arrival. Also, unless you have forward facing fusion nozzles, you are going to have to turn the ship around to brake it. You would also want to make very sure that the exhaust from the fusion jet downs not intersect anything.
Edit Note: The other advantage of the Dean/Abbott Drive is that I can use it as a maneuver drive in the atmosphere for streamlined ships with no problems. You are going to have problems with a fusion reaction drive in the atmosphere.
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The SITREP WRT the DGP material has been that was for a while. Last I heard, he was asking way too much for the rights to republish. It'll get there eventually, I guess, but at least we now have a ruling that it's not apocryphal, which is the next best thing to canon. Once Marc manages to get permission / rights, I guess it'll be returned to Canon, but it's going to be an interesting trip in the mean time.
WRT the various drives, I'm going with reactionless. It's easier to put them in place, and helps me out in the design. They're still going to have external thruster plates, though (yep, I took the point about additional cooling, etc).
Cheers for the continued thoughts
WRT the various drives, I'm going with reactionless. It's easier to put them in place, and helps me out in the design. They're still going to have external thruster plates, though (yep, I took the point about additional cooling, etc).
Cheers for the continued thoughts
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The SITREP WRT the DGP material has been that was for a while. Last I heard, he was asking way too much for the rights to republish. It'll get there eventually, I guess, but at least we now have a ruling that it's not apocryphal, which is the next best thing to canon. Once Marc manages to get permission / rights, I guess it'll be returned to Canon, but it's going to be an interesting trip in the mean time.
WRT the various drives, I'm going with reactionless. It's easier to put them in place, and helps me out in the design. They're still going to have external thruster plates, though (yep, I took the point about additional cooling, etc).
Cheers for the continued thoughts
Actually, last I heard he has come to the conclusion (delusion?) that they're worth nothing at all, and bothering to come to a deal would be a waste of his time and effort... Don was trying to broker a deal.
DGP is the first non-GDW source Don checked against. See, DGP wrote MegaTraveller for GDW... and all the DGP was (until GT) fully canonical as it was fully by the creative team for MT.
Then GT and MGT. Then the other apocrypha.
mike wightman
SOC-14 10K
It does, just preposterously little in the early days. 48 hours of continuous burn on a full load of fuel that also lasts the power plant for 4 weeks.
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AnotherDilbert
SOC-14 1K
In CT'77, but not in CT'81.
mike wightman
SOC-14 10K
And once again, they didn't overwrite it with any other explanation so 77/HG1 is the only explanation we had until DGP and MT.
An explanation that was rejected by GDW when the went to work on TNE Frank Chadwick wanted to go back to the original CT intention, a reaction drive that uses fuel.
An explanation that was rejected by GDW when the went to work on TNE Frank Chadwick wanted to go back to the original CT intention, a reaction drive that uses fuel.
AnotherDilbert
SOC-14 1K
In CT'81 M-drives explicitly does not use fuel, so reaction-less drives are the only conclusion.
I think we have to agree to disagree on this point.
mike wightman
SOC-14 10K
The power plant continues to use the same 4 week trope etc.
The maneuver drive is not defined as reactionless.
And nowhere does it explicitly say the maneuver drive doesn't use fuel, it just fails to mention it does possibly the authors assumed familiarity with earlier editions?
I agree to disagree.
The maneuver drive is not defined as reactionless.
And nowhere does it explicitly say the maneuver drive doesn't use fuel, it just fails to mention it does possibly the authors assumed familiarity with earlier editions?
I agree to disagree.
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AnotherDilbert
SOC-14 1K
Regarding the original question: In TNE Thruster Plates (that were explicitly the same tech as earlier editions) did require exterior surface area, so had to be mounted through the hull.
Timerover51
SOC-14 5K
If he truly feels that they are worth nothing at all, then he probably would not be willing to pay a lawyer a large amount of money to defend the copyright. If that is actually the case, someone might as well start reprinting them. If he objects, then he has to pay the money to sue.
Good point, but what is the liability exposure? If I, John Doe with no assets to speak of and not much in the way of income, decide to send PDFs to buddies or post them on my (nonexistent because I am talentless where web design is involved) blog, his legal rights extend to ordering me to stop and/or making the host company take down my site; having a lawyer pursue damages might be emotionally rewarding to him but would otherwise be a cost expended with no realistic chance of recovering much actual money.
On the other hand, if an organization like Citizens of the Imperium tried that game, taking down the site would have a huge impact on a larger audience than little-me-blogger could reach. If a company with real assets tried it, could he pursue damages on top of issuing a cease-and-desist?
More on topic, I played with a modular cutter variant that put the engines to either side of the forward bridge compartment. Instead of slinging the module between the two compartments, the module docked aft of the bridge compartment. This allowed the cutter to resupply ships in a fleet by backing up to the cargo bay of the cargo ship, docking with a module, then taking it to the receiving ship and backing it into that cargo bay.
The cargo bays were sized to fit the modules, so no time had to be spent loading or unloading the modules during fleet operations: the receiving ship could take off cargo when and as needed and, when it was empty, a cutter would bring a replacement, pull out the empty one, back in a new one, then dock with the empty and take it to the cargo ship. It also allowed a ship to readily convert cargo space into stateroom space by just having a cutter bring over a stateroom module.
Of course, that might well be the design the Old Timer was complaining about.
The cargo bays were sized to fit the modules, so no time had to be spent loading or unloading the modules during fleet operations: the receiving ship could take off cargo when and as needed and, when it was empty, a cutter would bring a replacement, pull out the empty one, back in a new one, then dock with the empty and take it to the cargo ship. It also allowed a ship to readily convert cargo space into stateroom space by just having a cutter bring over a stateroom module.
Of course, that might well be the design the Old Timer was complaining about.
Let's agree to nix this angle of the discussion, please - copyright is not always about cost, it's about creators rights as well, some of the time. Let's leave it at that, and get back on the topic at hand: Methods of generating thrust, and placement of said drives in a ship
Ta muchly
Let's agree to nix this angle of the discussion, please - copyright is not always about cost, it's about creators rights as well, some of the time. Let's leave it at that, and get back on the topic at hand: Methods of generating thrust, and placement of said drives in a ship
Discard that whole idea of "Creator's Rights" for US copyright - it's got VERY little to do with Copyright since the 1920's. (The 2010 revisions actually return a few creators rights to sold works - but not works for hire.) Essentially, the creator has no rights once he sells something, or if he creates it while hired by someone else to do so.
And Roger, for what it is worth, owns the copyrights, but was not, in any way, the creator of the DGP works. He bought those rights after all the "good stuff" was written.
Not you, but Roger Sanger - the guy who bought the copyrights when DGP shut down.
Let's agree to nix this angle of the discussion, please - copyright is not always about cost, it's about creators rights as well, some of the time. Let's leave it at that, and get back on the topic at hand: Methods of generating thrust, and placement of said drives in a ship
Agreed - at least while the man's alive. I am somewhat less scrupulous when it comes something that will otherwise be lost to time as the result of the passing of the author.
kilemall
SOC-14 5K
Hmm, forgot about Star Citizen ships and relevance to this topic.
They went into ship design with the idea of the ships modelling thrust accurately and the physics engine would do the work.
I think they have largely stuck with this, and so I can tell you that thrusters all over can be useful, but most end up centerline rear anyway.
Some, like the Cutlass, have outboard mains. Others swivel like the Freelancer.
Here is a collection of the 'ads' made by the major ship manufacturers for their product line. Good summation of the ships in movement as intended. They'll strike your Traveller eyes as most being small craft/fighters, but the main thruster placement might get some ideas percolating.
https://www.youtube.com/watch?v=oGcvxaoOrJs
They went into ship design with the idea of the ships modelling thrust accurately and the physics engine would do the work.
I think they have largely stuck with this, and so I can tell you that thrusters all over can be useful, but most end up centerline rear anyway.
Some, like the Cutlass, have outboard mains. Others swivel like the Freelancer.
Here is a collection of the 'ads' made by the major ship manufacturers for their product line. Good summation of the ships in movement as intended. They'll strike your Traveller eyes as most being small craft/fighters, but the main thruster placement might get some ideas percolating.
https://www.youtube.com/watch?v=oGcvxaoOrJs
