04-16-2018, 09:16 AM | #11 | |
Join Date: Feb 2005
Location: Doncaster, UK
|
Re: [Spaceships] Black powder Rockets?
Quote:
|
|
04-16-2018, 06:06 PM | #12 |
Join Date: Aug 2008
|
Re: [Spaceships] Black powder Rockets?
On the scale and at the TL you are talking, I'd suggest a Malf of about 6...maaaaybe 7. It'd probably be realistic to make it a Malf of 3....
__________________
Buy My Stuff! Free Stuff: Dungeon Action! Totem Spirits My Blog: Above the Flatline. |
04-17-2018, 02:38 AM | #13 |
Join Date: Feb 2005
Location: Doncaster, UK
|
Re: [Spaceships] Black powder Rockets?
Here's what I think I've worked out for the Estes E9-6.
From their chart, it has 25 N of thrust, an initial weight of 56.7 g and a propellant weight of 35.8 g. Wikipedia says its Isp is 85.51 Its acceleration is 25 / (0.0567 * 9.8) = 45 G If the whole rocket was a GURPS spaceship, it would have 13 chemical rocket components and 7 fuel tank components. So the acceleration of one chemical rocket is 45 / 13 = 3.46 G The delta-v per tank is 85.51 / 3000 = 0.03 mps Does this seem cromulent? |
04-17-2018, 07:26 AM | #14 |
Join Date: Aug 2007
|
Re: [Spaceships] Black powder Rockets?
It seems unlikely to be related to your basic question.
__________________
Fred Brackin |
04-18-2018, 02:44 AM | #15 |
Join Date: Feb 2005
Location: Doncaster, UK
|
Re: [Spaceships] Black powder Rockets?
|
04-19-2018, 02:12 AM | #16 | ||||
Join Date: May 2005
Location: Oz
|
Re: [Spaceships] Black powder Rockets?
Quote:
Quote:
Quote:
Quote:
__________________
Decay is inherent in all composite things. Nod head. Get treat. |
||||
04-19-2018, 11:29 AM | #17 |
Join Date: Sep 2004
Location: Canada
|
Re: [Spaceships] Black powder Rockets?
Mythbusters also took a shot at Lagâri Hasan Çelebi, but really there were problems with both the Ming Dynasty Astronaut and Lagâri Hasan Çelebi's vehicle, even beyond the propellant question.
The Ming Dynasty Astronaut's "vehicle" was said to be a throne. It was going to flip over and smash even if it didn't explode. Lagâri Hasan Çelebi's vehicle is pretty sketchy in description, but generally is agreed to be a sort of open-topped barrel-type thing... which is neither aerodynamic, nor air-tight, and he was supposed to stand in it so even more unstable there. So both are (as originally told) pretty mythological (Çelebi's "parachute" is about as plausable as Icharus' wings too) even assuming modern motors. The mythbusters used modern motors for both tests, btw, because of health-and-saftey concerns, not that this stopped the Ming Dynasty Astronaut test from exploding - they were not made to be packed in something like a 16x16 grid under a wooden throne with basically-simultaneous ignition. Both stories, however, highlight the problem that the rockets are really only one of the problems that a TL 4-ish astronaut is going to struggle with. You need an aerodynamic stable body that isn't going to just flip over in flight, you really want to have some control over it beyond "light the fuse and pray to the deity of your choice", it has to be air tight, and you need to somehow bring enough air that your crew doesn't promptly suffocate (or you need a chemical air scrubber, which is even more technology and weight).
__________________
All about Size Modifier; Unified Hit Location Table A Wiki for my F2F Group A neglected GURPS blog |
04-19-2018, 11:35 AM | #18 | |
☣
Join Date: Sep 2004
Location: Southeast NC
|
Re: [Spaceships] Black powder Rockets?
Quote:
__________________
RyanW - Actually one normal sized guy in three tiny trenchcoats. |
|
04-19-2018, 11:41 AM | #19 |
Join Date: Feb 2005
Location: Berkeley, CA
|
Re: [Spaceships] Black powder Rockets?
BP rockets are low enough temperature that you could structure your system with the payload behind the rocket. Still an explosion risk, of course, but not dynamically unstable.
|
04-19-2018, 11:59 AM | #20 |
Join Date: Apr 2005
|
Re: [Spaceships] Black powder Rockets?
If you mean a pendulum rocket, unfortunately those are no more stable than conventional layouts. The force of the rocket is fixed along the axis of the rocket rather than the axis of gravity (As we would usually think of a normal pendulum), so it provides no correcting force.
|
Tags |
blackpowder, gunpowder, rocket, spaceships |
|
|