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Old 12-28-2020, 12:29 PM   #21
tshiggins
 
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Default Re: Cinematic Rocket Delta-V Rules

Honestly, I think the Epstein Drive from The Expanse would do the job, for you.

Beware! All of the links include at least some spoilers about the TV show and the novel series!


Youtuber Scott Manley (who has a degree in Astronomy) provides an overview, here:
https://www.youtube.com/watch?v=SIaGXcEnC74

He goes a bit more into the mathematics of the Epstein Drive, here:
https://www.youtube.com/watch?v=JWZqp0QoXcw

Winchell Chung over at Atomic Rockets also looks at some of the other aspects of the show (which he obviously loves):
http://www.projectrho.com/public_htm...s--The_Expanse

I have to agree with previous advice that says to figure out what you want to accomplish, with your setting, and then build your technology to fulfill that goal.

The Epstein Drive turns every ship -- and its cargo -- into amazing WMDs. With something like that, a ship just needs some mass-drivers to put dumb cannon-balls -- or even shotgun pellets -- on needed trajectories, because the energy they have at those velocities will vaporize anything they hit.

If you want smart missiles and lazors and stuff, then you need to a reason those expensive systems work better than simple guns firing dense pellets.

For that, you need to slow down the ship's actual velocity, while keeping Solar System travel times to days or weeks, instead of months or years.

A pseudo-velocity drive, such as the "blink-warp" (a version of 2300AD's "stutter-warp" drive rendered in GURPS rules) or something would do the trick for you.

The discussion re-emerges periodically, so here's a link to the thread on these boards where I first went into it. It's post #35.
http://forums.sjgames.com/showthread...n+stars&page=4

Basically, forbid the FTL threshold and just say that, once a ship gets far enough out of a gravity well, the stutter-warp allows for the useful pseudo-velocity to allow it to travel around the system.

Inside the well, it has to use more traditional (and realistic) maneuver drives of whatever type best fits your setting.
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Old 12-28-2020, 01:03 PM   #22
Michael Thayne
 
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Default Re: Cinematic Rocket Delta-V Rules

I don't know about Battletech, but I think the Epstein Drive from The Expanse should probably be modeled as a super fusion pulse drive (SS p. 22), but without the benefit of gravitic compensators (SS p. 29), so acceleration is limited by what the crew can withstand. If you have Spaceships 7 you can use the smaller systems to downgrade to a small-sized fusion pulse drive, which still gives you ~6.7G of acceleration, which is plenty for a craft with a biological crew. Really getting the feel of The Expanse probably calls for homebrewing more detailed rules for the effects of high-G maneuvers, as well as biotech to mitigate them.

OTOH, if you just not want to worry about delta-V as little as possible without technically breaking any laws of physics the total conversion torch (SS p. 23) will do the job nicely.

A third option would be to use reactionless drives, but have them run out of fuel as the plot demands. That might be more what you're thinking of by "cinematic"ónot so much impossibly powerful as following movie logic rather than real-world logic.
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Old 12-28-2020, 03:02 PM   #23
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Default Re: Cinematic Rocket Delta-V Rules

Quote:
Originally Posted by tshiggins View Post
Honestly, I think the Epstein Drive from The Expanse would do the job, for you.

Beware! All of the links include at least some spoilers about the TV show and the novel series!


Youtuber Scott Manley (who has a degree in Astronomy) provides an overview, here:
https://www.youtube.com/watch?v=SIaGXcEnC74

He goes a bit more into the mathematics of the Epstein Drive, here:
https://www.youtube.com/watch?v=JWZqp0QoXcw

Winchell Chung over at Atomic Rockets also looks at some of the other aspects of the show (which he obviously loves):
http://www.projectrho.com/public_htm...s--The_Expanse

I have to agree with previous advice that says to figure out what you want to accomplish, with your setting, and then build your technology to fulfill that goal.

The Epstein Drive turns every ship -- and its cargo -- into amazing WMDs. With something like that, a ship just needs some mass-drivers to put dumb cannon-balls -- or even shotgun pellets -- on needed trajectories, because the energy they have at those velocities will vaporize anything they hit.

If you want smart missiles and lazors and stuff, then you need to a reason those expensive systems work better than simple guns firing dense pellets.

For that, you need to slow down the ship's actual velocity, while keeping Solar System travel times to days or weeks, instead of months or years.

A pseudo-velocity drive, such as the "blink-warp" (a version of 2300AD's "stutter-warp" drive rendered in GURPS rules) or something would do the trick for you.

The discussion re-emerges periodically, so here's a link to the thread on these boards where I first went into it. It's post #35.
http://forums.sjgames.com/showthread...n+stars&page=4

Basically, forbid the FTL threshold and just say that, once a ship gets far enough out of a gravity well, the stutter-warp allows for the useful pseudo-velocity to allow it to travel around the system.

Inside the well, it has to use more traditional (and realistic) maneuver drives of whatever type best fits your setting.
Well, my partner and I have been using Transhuman Space's High-Efficiency Plasma Recombustion Fusion Rocket (HePlaR) as a basis.

Though, the Epstein Drive could be interesting, although I'll have to convert it into GURPS Vehicle Builder first...
Quote:
Originally Posted by Michael Thayne View Post
I don't know about Battletech, but I think the Epstein Drive from The Expanse should probably be modeled as a super fusion pulse drive (SS p. 22), but without the benefit of gravitic compensators (SS p. 29), so acceleration is limited by what the crew can withstand. If you have Spaceships 7 you can use the smaller systems to downgrade to a small-sized fusion pulse drive, which still gives you ~6.7G of acceleration, which is plenty for a craft with a biological crew. Really getting the feel of The Expanse probably calls for homebrewing more detailed rules for the effects of high-G maneuvers, as well as biotech to mitigate them.

OTOH, if you just not want to worry about delta-V as little as possible without technically breaking any laws of physics the total conversion torch (SS p. 23) will do the job nicely.

A third option would be to use reactionless drives, but have them run out of fuel as the plot demands. That might be more what you're thinking of by "cinematic"—not so much impossibly powerful as following movie logic rather than real-world logic.
Thank you for the input.
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Originally Posted by AlexanderHowl View Post
Superscience and magic are unrealistic, but they are not necessarily cinematic (you can have FTL or spell casting in a noncinematic setting). The primary issue with even limited superscience drives in such a setting is that inertia becomes the ultimate weapon. Even at 35 mps per fuel tank, a spacecraft with 10 fuel tanks can reach 490 mps easily, meaning that every ton of remaining mass is equivalent to 68.5 kilotons of TNT, meaning that civilian terrorists can turn a SM+9 merchant ship in a full scaled Tsar Bomba. Even a SM+4 AKV becomes much more valuable as a WMD than as a combatant, as it would be the equivalent of over 340 kilotons of TNT at full speed.
Well, the core problem with that is 1) everyone and their brother sees you doing that and tries to kill you before it happens, 2) there are safeguards put in place to prevent that scenario, 3) the smallest dedicated anti-ship laser cannon is a 1GJ (or 5TW, whatever you prefer) UV Pulse Laser with a range of 40Mm, 4) similar drives are fitted to Cassaba Howitzer (shaped charge nuclear warheads) and nuke-pumped laser heads, which well in exceed any ship's armor belt (five huge 400mm nuclear warheads are no joke).
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Old 12-28-2020, 03:13 PM   #24
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Default Re: Cinematic Rocket Delta-V Rules

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Originally Posted by GURPS Fox View Post
Well, my partner and I have been using Transhuman Space's High-Efficiency Plasma Recombustion Fusion Rocket (HePlaR) as a basis.
HEPlaR is Traveller: The New Era, not Transhuman Space.
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Old 12-28-2020, 08:55 PM   #25
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Default Re: Cinematic Rocket Delta-V Rules

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Originally Posted by Michael Thayne View Post
I don't know about Battletech,.
Battletech's "fusion drive" needs to be Total Conversion. They run it at multi-G settings for _days_.

I have forgotten how far out their standard jump points ar ebut I bet te web will tell me.

https://apps.facebook.com/candycrush...=0&fb_bmpos=_0

....says that the zenith or nadir jump points for a G2 like uour sun are 1.5 billion km away. In round numbers that's 10 AU and for a continuous accel/decel it'll take 215 hours at 21.6 miles per second of delta-V every hour that adds up to 4645 miles per second of Delta-v.

You might be able to make a ship in Spaceships that could do that with the second-best drive for Delta-V but it'll be almost all fuel tanks. It' almost certainly need to refuel before heading back to the jump point too.

You can take the Total Conversion stats and re-name them to anything you like but of one of Fred's Laws of Space Setting Design is to not to send ships off to the backside of a solar system on a routine basis. No good comes of it.
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Old 12-30-2020, 10:20 AM   #26
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Default Re: Cinematic Rocket Delta-V Rules

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Originally Posted by tshiggins View Post
A pseudo-velocity drive, such as the "blink-warp" (a version of 2300AD's "stutter-warp" drive rendered in GURPS rules) or something would do the trick for you.

The discussion re-emerges periodically, so here's a link to the thread on these boards where I first went into it. It's post #35.
http://forums.sjgames.com/showthread...n+stars&page=4

Basically, forbid the FTL threshold and just say that, once a ship gets far enough out of a gravity well, the stutter-warp allows for the useful pseudo-velocity to allow it to travel around the system.
This very closely matches my own conclusions about the "perfect drive" for a space-opera setting. In short, I think that GDW got it right in 2300AD with the mechanics of the Stutterwarp. It falls short in only a couple of places.

Basically, in most Space Operas you want all of the "tropes", right? And they all come down to cheap space travel at ridiculous velocities, without world-destroying power in the hands of every skipper. (You also need cheap launch fees to orbit.) Such tropes include interstellar trade, individual ownership of tramp freighters, piracy, non-geriatric travel times, a reason that interstellar travel is space-based rather than using projectors on a planetary surface, space mining, combat being something other than 100% mutual destruction (so spaceship armor has to be a thing), etc. Arguably, in any "realistic" setting none of these are very likely to exist. And it is nice to have a reason for ships to zoom all around a system rather than just pop into existence very close to the destination world as happens in Traveller, because that just leaves you playing your games in tiny bubbles around inhabited worlds.

With a Stutterwarp-like (in GURPS terms) pseudovelocity warp drive with subwarp capability all you need is power, no propellant (or at least very little). You can make the acceleration (or even top speed) be whatever you need it to be arbitrarily. I personally like the idea of quantized gradients a la 2300AD: there is a limit close to a gravity well where the drive does not function, beyond that a limit in which it functions at low efficiency, maybe one more higher-efficiency quantum gradient, and finally a gradient way out in low-gravity regions where it achieves superluminal travel. And an Alcubierre drive makes excellent technobabble for this!

So, there is your cheap space travel! Now you just need cheap launch fees to orbit and suddenly interstellar trade becomes a possibility, and there are lots of ways to handwave cheap launches, especially if you ignore the radiation hazards of fission/fusion/antimatter drives. Or heck, just make elevators or Lofstrom loops ubiquitous.

So, where does this model fail?

Well, one place is that it doesn't innately make your tramp cargo ship able to land and take off from planets easily and cheaply. Under this pseudovelocity warp model there would almost certainly be trans-shipment in orbit to some sort of system for launching/landing the cargo. So you would need a ship's shuttle or somesuch for landings. Due to my sensibilities I personally find this to be a feature rather than a bug, but opinions will differ. You will never somewhat realistically get your tramp freighter to land on or take off from an inhabited planet cheaply, unless you resort to unfortunate things like reactionless drives or antigravity, because any remotely realistic drive that can do it spews radioactive death.

Another is that pseudovelocity drives realistically would not be able to be used to simulate gravity, so while zooming all over the place these ships are still in free fall. Thus you probably either need artificial gravity (which should leave a bad taste in your mouth, and usually leads to heartrending stuff like antigravity and antigravity drives)... or spin gravity in your ships. 2300AD tended to have spin gravity in its ships, FWIW. To me this is an annoyance, but a minor one. I would prefer to have crews deal with high Gs, etc.

This system also does lack the need to refuel your ship often. Which is a major bummer. Unless, like Traveller, you introduce an entirely arbitrary fuel need to fuel the warp drive.

And finally, the one that really does annoy me. I would prefer to have the full range of starship ordnance available, but it turns out to be very difficult to have various ballistic attacks connect with a warping ship, so you are left with only one: warp torpedoes. This is also what 2300AD does- and in fact all of them are detonation lasers, too. This is particularly apropos if you use an Alcubierre drive as your technobabble, since the warp field tends to destroy any matter that crosses it, converting it into a shower of radiation. Beam weapons might work, too, at least canonically by the combat rules in Spaceships, but when you're talking about ships maneuvering at 1000Gs it gets hard to believe that combat closes to distances where they might be useful.

Finally, I personally would like one aspect of interstellar travel which, again, IMHO 2300AD got right. I don't want to just be able to warp from any system to any other system directly. When you can do that all warfare degenerates into massive Mahanian battles, which I find uninteresting. I want there to be strategic "space lanes" and allowance for maneuver. Putting a limit on how far an interstellar drive can go in one jump does this naturally. There will be strategic systems that one needs to transit to get to others, etc. In 2300AD a warp drive developed a "charge" as it was used that would lead to destruction of the ship if it traveled more than 7.7 light years. (And after playing around with Astrosynthesis I have decided that 8-10 light years works well on a real near-star map, depending upon just how complex you want your options to be, without orphaning any of the more interesting systems.) After that, the ship HAD to drop down into a gravity well to the point that the drive didn't work in order to "discharge" it's drives. This meant that transiting a system also involved finding a planet at which to discharge your drives, so for instance military bases might be made at convenient planets.

This need to discharge a drive after a certain distance can be used with any drive, not just the warp drive, of course. And it so perfectly forces more interesting interstellar travel (space lanes, a reason to drop closer to planets when transiting a system, etc.) that I highly recommend it. It also has interesting tactical features, too. For instance, if you try to attack another system that is more than half the total distance possible you can't retreat back to your system of origin without finding a planet at which to discharge drives (which will probably be defended).

Just my $0.02.

[MANIFESTO]

If I could come up with a space travel system (realspace and stardrive combination) that covered everything I wanted I'd change in a heartbeat, but this is the closest I can come. FWIW what I want is:

1. Cheap and fast space travel, both realspace and interstellar
1a. Interstellar Trade
1b. Tramp freighters
1c. Space piracy
1d. Non-geriatric travel times (no more than a few months between systems)
2. No world-destroying power in the hands of every ship skipper
2a. Ridiculous velocities are tolerable, so long as there are limits and countermeasures
2ai. If it takes a reasonable time to accelerate and drives are highly visible, it's ok.
2aii. Nothing undefendable, e.g. 1000s of Gs real acceleration without an easily detectable signature.
3. No heartrending technology
3a. No reactionless drives
3b. No antigravity
3c. No time travel
3d. "Limited-superscience" is acceptable, but I'd like to avoid overt superscience.
4. No spewing radioactive death from drives, because...
4a. Starships (at least some) can land on planets
5. Need for significant fuel or reaction mass replenishment
5a. Very powerful reaction drives are ok, so long as not WMD
5b. But most reaction drives are actually very poorly collimated, and thus acceptable.
6. Interesting space warfare, both strategically and tactically
6a. Defined "space lanes"
6b. Strategic systems and choke points in the space lanes
6c. Full range of space weapons viable (ballistic, energy, missile)
6d. No MAD in all space combat, which probably requires armor
7. A reason for ships to travel through a system, not just jump straight to a destination world.

Obviously, this system does not exist.

[/MANIFESTO]

Last edited by acrosome; 12-30-2020 at 11:37 AM.
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Old 12-30-2020, 10:46 AM   #27
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Default Re: Cinematic Rocket Delta-V Rules

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Originally Posted by Fred Brackin View Post

(SNIP)

You can take the Total Conversion stats and re-name them to anything you like but of one of Fred's Laws of Space Setting Design is to not to send ships off to the backside of a solar system on a routine basis. No good comes of it.
Stolen!

(That's really funny.)
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Old 12-30-2020, 11:34 AM   #28
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Default Re: Cinematic Rocket Delta-V Rules

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Originally Posted by acrosome View Post

(SNIP)

So, where does this model fail?

Well, one place is that it doesn't innately make your tramp cargo ship able to land and take off from planets easily and cheaply. Under this pseudovelocity warp model there would almost certainly be trans-shipment in orbit to some sort of system for launching/landing the cargo. So you would need a ship's shuttle or somesuch for landings. Due to my sensibilities I personally find this to be a feature rather than a bug, but opinions will differ. You will never somewhat realistically get your tramp freighter to land on or take off from an inhabited planet cheaply, unless you resort to unfortunate things like reactionless drives or antigravity, because any remotely realistic drive that can do it spews radioactive death.
Yep, and I also consider this a "feature" and not a bug, because it gives the GM some dramatic options, without upsetting the players too much.

A lot of science fiction settings present the spacecraft owned or operated by the main characters as a special haven.
The Doctor has the TARDIS
Blake's 7 had Liberator
Star Trek has the Enterprise
Star Wars has the Millennium Falcon
Firefly had Serenity
The Expanse has the Rocinante

If the players must drop to a planet's surface with a shuttle, it can get wrecked, or taken over, or otherwise interfered with, and that can offer some fun drama.

However, because it doesn't mess with the ship, the players are a lot less likely to get really upset by the situation.

Plus, flying a shuttle down for difficult landings gives the pilot character more to do, and it offers other options such as air-drops, evacs, and other fun things. And all of that is in addition to the fact that it just makes sense.

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Originally Posted by acrosome View Post
Another is that pseudovelocity drives realistically would not be able to be used to simulate gravity, so while zooming all over the place these ships are still in free fall. Thus you probably either need artificial gravity (which should leave a bad taste in your mouth, and usually leads to heartrending stuff like antigravity and antigravity drives)... or spin gravity in your ships. 2300AD tended to have spin gravity in its ships, FWIW. To me this is an annoyance, but a minor one. I would prefer to have crews deal with high Gs, etc.
I don't have any problem with spin habitats. They make spacecraft look like spacecraft, and not aircraft.

A pencil through a doughnut becomes a rational design, as do extensible habitat pods. That also means you put the bridge in the artificial gravity section (since the crew spends so much time, there), and not in the central fuselage.

That allows you to put a big cargo-lift down the middle of a cargo spacecraft, with doors that open into cargo holds around the perimeter, and the nose of the ship is a big air-lock that opens directly into a station.

As for high-G burns, yeah, The Expanse uses those to enhance the drama during crises, and that's pretty cool because it makes space feel like space. But I think it's worth the sacrifice to give that up, if it avoids other issues that create real problems for the setting.

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This system also does lack the need to refuel your ship often. Which is a major bummer. Unless, like Traveller, you introduce an entirely arbitrary fuel need to fuel the warp drive.
You mention the need to discharge coils, below, which is (effectively) the same thing.

The authors of The Expanse didn't even worry about fuel. The Roci has enough fusion pellets to fly for 20-30 years.

However, the crew still needs air, ammo, water, food and (especially) coffee, and that takes them back to a base (usually Tycho Station), periodically, and forces them to interact with people, there.

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Originally Posted by acrosome View Post
And finally, the one that really does annoy me. I would prefer to have the full range of starship ordnance available, but it turns out to be very difficult to have various ballistic attacks connect with a warping ship, so you are left with only one: warp torpedoes. This is also what 2300AD does- and in fact all of them are detonation lasers, too. This is particularly apropos if you use an Alcubierre drive as your technobabble, since the warp field tends to destroy any matter that crosses it, converting it into a shower of radiation. Beam weapons might work, too, at least canonically by the combat rules in Spaceships, but when you're talking about ships maneuvering at 1000Gs it gets hard to believe that combat closes to distances where they might be useful.
Yeah, close-quarters battles do not happen with stutter-warps/blink-warps, which is kind of a shame, and nobody's going to board one that isn't already in orbit, somewhere.

Not that CQB is all that realistic, anyway, but it is fun. :)

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Originally Posted by acrosome View Post
Finally, I personally would like one aspect of interstellar travel which, again, IMHO 2300AD got right. I don't want to just be able to warp from any system to any other system directly. When you can do that all warfare degenerates into massive Mahanian battles, which I find uninteresting. I want there to be strategic "space lanes" and allowance for maneuver. Putting a limit on how far an interstellar drive can go in one jump does this naturally. There will be strategic systems that one needs to transit to get to others, etc. In 2300AD a warp drive developed a "charge" as it was used that would lead to destruction of the ship if it traveled more than 7.7 light years. (And after playing around with Astrosynthesis I have decided that 8-10 light years works well on a real near-star map, depending upon just how complex you want your options to be, without orphaning any of the more interesting systems.) After that, the ship HAD to drop down into a gravity well to the point that the drive didn't work in order to "discharge" it's drives. This meant that transiting a system also involved finding a planet at which to discharge your drives, so for instance military bases might be made at convenient planets.
This substitutes for re-fueling, well enough, I think, and I liked it for that reason, also.

Now then, when the GDW design team created the Near Star Map for 2300AD, they deliberately chose to leave out a bunch of the red dwarf stars, because they wanted the various "Arms" to have distinct travel paths.

The presence of red dwarfs allowed multiple routes to all destinations, although the initial push out to Wolf359 still required a tug, unless someone wanted to take a really long way around.

That creates a bunch of poorly-patrolled systems -- and some not patrolled, at all -- well away from the main space-lanes, but with access to them.

I think the decision to drop those red dwarf stars resulted in some real missed opportunities. If a ship wanted to slip around quietly and try to avoid patrols, that's pretty tough in the canon Near Star Map, but inclusion of all the stars makes that possible.

There are all sorts of other shenanigans people can get up to, with remote star systems well off the beaten path.

Quote:
Originally Posted by acrosome View Post
This need to discharge a drive after a certain distance can be used with any drive, not just the warp drive, of course. And it so perfectly forces more interesting interstellar travel (space lanes, a reason to drop closer to planets when transiting a system, etc.) that I highly recommend it. It also has interesting tactical features, too. For instance, if you try to attack another system that is more than half the total distance possible you can't retreat back to your system of origin without finding a planet at which to discharge drives (which will probably be defended).

Just my $0.02.
Agree wholeheartedly!

Quote:
Originally Posted by acrosome View Post

[MANIFESTO]

(SNIP)
Yeah, that's a lot.

Any GM must make tradeoffs, but it's best to try to sacrifice as little as possible from the list of desirable features. I think the 2300AD stutter-warp does that better than anything I've seen, thus far.
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Old 12-30-2020, 12:23 PM   #29
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Default Re: Cinematic Rocket Delta-V Rules

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I don't have any problem with spin habitats. They make spacecraft look like spacecraft, and not aircraft.

A pencil through a doughnut becomes a rational design, .
Well, maybe after you've made the irrational (but trope-necessary) decison to have crews of organic beings.

I consider artifiical gravity but another trope necessary thing, It's all small potatoes after you've swallowed FTL and non-geriactric realspace propulsion.

I disagree about blink-warp though. I try and visualize how a blink-warp ship interacts with the normal universe and it's all gibberish.
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Old 12-30-2020, 01:12 PM   #30
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Default Re: Cinematic Rocket Delta-V Rules

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I disagree about blink-warp though. I try and visualize how a blink-warp ship interacts with the normal universe and it's all gibberish.
Yes, me too. That's why I specified that I liked the game mechanics of the Stutterwarp, not the technobabble. I'd pick different technobabble, like an Alcubierre drive of some sort.

Quote:
Originally Posted by tshiggins View Post
Now then, when the GDW design team created the Near Star Map for 2300AD, they deliberately chose to leave out a bunch of the red dwarf stars, because they wanted the various "Arms" to have distinct travel paths.

The presence of red dwarfs allowed multiple routes to all destinations, although the initial push out to Wolf359 still required a tug, unless someone wanted to take a really long way around.

That creates a bunch of poorly-patrolled systems -- and some not patrolled, at all -- well away from the main space-lanes, but with access to them.

I think the decision to drop those red dwarf stars resulted in some real missed opportunities. If a ship wanted to slip around quietly and try to avoid patrols, that's pretty tough in the canon Near Star Map, but inclusion of all the stars makes that possible.

There are all sorts of other shenanigans people can get up to, with remote star systems well off the beaten path.
One of my long-term projects is making a 2D projection of a "subway map" style of near star map, based upon an 8 light year jump limit, and leaving all of the red dwarfs and whatever brown dwarfs I could find info on in place. It is definitely more complex than 2300AD's map, but still results in interesting choke points. They are just on a larger scale than in 2300AD, where every route is essentially linear. And it still has lots of obscure and remote systems to hide in, and doesn't orphan any interesting systems (IIRC Fomalhaut is one example, as anything shorter leaves it inaccessible). There are numerous spots where a cluster of systems is only accessible to the rest of the map through one or two of them, for example. And there is a Great Ring Route that includes Sol. It's turning out nicely.

I was frankly surprised that nobody seems to have done it before. I'm using Astrosynthesis and some data from the Lair of Evil Doctor Ganymede. The hard part is getting it into a 2D display. It would be nice if I could find software that would spit out a subway map automagically, but I can't, so I'm doing it by hand.

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Yeah, that's a lot.

Any GM must make tradeoffs, but it's best to try to sacrifice as little as possible from the list of desirable features. I think the 2300AD stutter-warp does that better than anything I've seen, thus far.
Well, we can pontificate about what such a system would look like. Really, it would just need an insanely powerful and efficient reaction drive of some sort. In short, a torch ship. But make it not spew radioactive death. Then, designing an appropriate stardrive is much easier.

I have just never been willing to allow such a ludicrously unrealistic reaction drive, is all.

An idea that I toyed with was some sort of ladderdown power source. There is a triology of indie-published books on Amazon (the first is titled Torchship) that seems to use one, in addition to Will McCarthy's Bloom. But those are pretty fringe. They also have follow-on implications that are rather dramatic. Similar for other forms of mass conversion.

Last edited by acrosome; 12-30-2020 at 02:09 PM.
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