02-23-2020, 04:23 PM | #11 |
Join Date: Nov 2018
Location: Live in Seoul, Korea and I have never been abroad.
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Re: Coolant [Spaceships]
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02-23-2020, 04:28 PM | #12 | |
Join Date: May 2005
Location: Oz
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Re: Coolant [Spaceships]
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But when you're talking about mass destruction…. A city is a big enough target not to need terminal guidance to hit it. And it moves in a slow and predictable way that means you don't need sensors to find it. A packet of orbital crowbars or a big long rod from God is going to have an atrocious effect even at "only" 7.8 km/s. That's only 0.000 026 times the speed of light. You don't need relativistic or even 0.001 c impactors to blow a large city off the map. Any thousand-tonne spaceship in or capable of reaching low orbit is a potential seven-kiloton bomb.
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Decay is inherent in all composite things. Nod head. Get treat. Last edited by Agemegos; 02-23-2020 at 05:43 PM. |
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02-23-2020, 04:42 PM | #13 | |
Join Date: Aug 2004
Location: Wellington, NZ
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Re: Coolant [Spaceships]
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02-23-2020, 04:45 PM | #14 |
Join Date: Aug 2004
Location: Binghamton, NY, USA. Near the river Styx in the 5th Circle.
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Re: Coolant [Spaceships]
I'm presuming they use Tungsten because it has 3x the density of Iron. This allows it to have a smaller cross section and carry more kinetic energy to the ground. I presume they would have some sort of protective coating, and maybe an ablative end cap for reentry; that combined with the long thin reentry profile, the idea is to not have them slow down too much in the atmosphere and thus not heat up enough to melt.
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Eric B. Smith GURPS Data File Coordinator GURPSLand I shall pull the pin from this healing grenade and... Kaboom-baya. |
02-23-2020, 05:40 PM | #15 | |
Join Date: May 2005
Location: Oz
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Re: Coolant [Spaceships]
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But anyway, the impracticality of Project Thor is admitted but not important, and spaceships are unlikely to be built out of tungsten. The point was that any spaceship in or capable of reaching low orbit is weapons-grade. It's the very least and most inescapable demonstration of Jon's Law: "any interesting space drive is a weapon of mass destruction".
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Decay is inherent in all composite things. Nod head. Get treat. Last edited by Agemegos; 02-23-2020 at 06:10 PM. |
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02-23-2020, 05:59 PM | #16 |
Join Date: Jun 2013
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Re: Coolant [Spaceships]
Replacing reaction mass with something else that gets used up (typically some sort of energy-producing fuel, but coolant could be an option) can be interesting from a background standpoint, but typically doesn't have a lot of impact on how ships function in the setting (aside from letting you ignore the issue of dangerous exhaust). Coolant can be a particularly interesting variant, because one can (presumably) use it a few different ways. A vessel with resupply readily available nearby can keep itself comfortably cool by venting coolant (probably using heat pumps to shunt heat into a small portion of it, boiling it, then releasing the steam). One that needs to be more conservative is going to tend to get rather warm during engagements and the like, as the coolant keeping the thrusters, power plants, and weapons from melting has no choice but to evenly distribute all that heat throughout the ship, radiating what little heat it can into the vacuum of space passively. In a crisis situation, the captain may have to make the difficult choice between venting coolant to keep important components (like the crew) from overheating or having enough available to be able to get back home in a reliable timeframe (or just have enough to get through the next battle). It may also influence tactics and decision-making from the other side ("Captain, their ship appears to be out of coolant. If we keep pursuing them, they're going to have a complete meltdown of their thrusters; the resulting antimatter explosion will almost certainly kill their hostages.").
What replacing reaction mass with coolant doesn't get you, however, is a useful spaceship that cannot be used as a WMD. For that, you've more-or-less got to break physics - teleportation, pseudovelocity, hyperspace travel, etc. Heck, even those still get you WMD's in the form of orbital drops, so you've got to combine them with the sort of social structures that prevent that.
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02-23-2020, 06:05 PM | #17 | |
Join Date: May 2005
Location: Oz
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Re: Coolant [Spaceships]
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You may be thinking of the heat shielding that is required for spacecraft that rely on aerobraking to shed significant speed. Remember that those are designed and put on trajectories that maximise the transfer of energy and momentum to the air, whereas an orbital-kinetic-energy weapon would be designed and deployed to minimise friction, not maximise it.
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Decay is inherent in all composite things. Nod head. Get treat. |
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02-23-2020, 08:57 PM | #18 | |
Join Date: Jan 2005
Location: Charlotte, North Caroline, United States of America, Earth?
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Re: Coolant [Spaceships]
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I still haven't wrapped my head around it completely, but it seems like there is almost a need for a rather strict protocol for spaceship ownership and operation.
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02-23-2020, 09:25 PM | #19 | |
Join Date: May 2005
Location: Oz
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Re: Coolant [Spaceships]
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It you go that way you have to think carefully about what (if anything) you were getting out of letting PC types have ownership or control of spaceships, and how to retain that. Of course one of the possibilities is to ignore Jon's law as a genre convention, to agree that the WMD potential of spaceships will simply not be used or mentioned, to preserve the jolly Star Wars or Traveller vibe. If you're doing that, then in my opinion the best thing is to offer only a simple rationalisation or none. Detail draws attention (especially the attention of SF fans), and you want players thinking about something else. ___________ * The SF RPG I used for that setting, ForeSight, had some grumbling at the beginning of the spaceship design and construction rules along the lines of "What would an SF RPG be without spaceship design and construction rules? I wanted to help you find out, but…". The chapter ended with something like "There you go, then. Yes, they are expensive, aren't they? Fly Galactic, and avoid used-spaceship dealers."
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Decay is inherent in all composite things. Nod head. Get treat. |
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02-23-2020, 09:29 PM | #20 | |
Join Date: Jul 2008
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Re: Coolant [Spaceships]
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Tags |
sci fi, spaceships |
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