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Rune

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Everything posted by Rune

  1. It saves "some" orientation. I know because when you load the same save a lot of times (because, say, you keep on getting the suicide burn wrong, not that that's happened to me... ^^'), it will always start with the same orientation... which has nothing to do with the orientation you left the craft in. Rune. File that as quirks of the game.
  2. Quite the opposite, for a given rotational period (rpm's), the "centrifugal force" (which is not a real force) is directly proportional to the turning radius. So the longer the "rope" is, the slower you turn for the same acceleration. In fact, at very short distances, the acceleration may become significantly different between your head and toes, so that would feel incredibly weird. Plus coriolis would become more significant, relatively speaking. Still, the energy contained in the system would be the same for the same acceleration and mass, so the length would not matter in the energy requirements to spin it up. Only a longer rope would be heavier, so it would matter in real life. For a practical number, around 50m radius would be OK (longer even better), but forget about centrifuges ~10m in diameter, unless you just want a small fraction of a G, or you just use them as beds. Studies seem to indicate somewhere between 6 and 10 rpm humans get sick (as in motion sickness sick) due to coriolis effects.
  3. Amazing what you can get on the internet these days. Rune. Mom, can I have a rocket engine for christmas?
  4. I just read the agreement you refer to: more paper studies, not a cent changes hands, and no one commits to any real metal-bending. So it might be good PR, but I wouldn't be holding my breath for a moonbase. As to liquid rockets, if you have access to a lathe or something similar, I would just try to build my own. You will learn a gazillion times more, you can make it small so you don't blow your house up when (not if) something goes wrong, and you can choose safer fuels and oxidizers. Like hydrogen peroxide and alcohol, I recommend starting there. Pressure-fed is also way easier and safer.
  5. You know the first thing that crosses my mind every time I see grasshopper land? Especially this time with the cool aerial footage... There's a spaceship landing "like God and Robert Heinlein meant them to". Rune. And then there's a big grin plastered on my face.
  6. Well, there's propellers. Assuming you have a compact and light fusion reactor (probably part of your main drive) you can get essentially unlimited electric supply, and then electric fans can be just as effective as wings, and allow hover. Wasted weight outside atmo, but... it would look cool as boop.
  7. Holy crap, that is scary. You really can just buy that? As a private citizen? Turbopump, thrust vectoring, igniter, digital control system... that is a very advanced and complicated engine. I would love to take one of those apart! But I would be very, very careful about fueling it, or lighting it. As in "only under expert supervision", and I'm studying to build that short of stuff. Rune. You would think that's the kind of thing that falls under ITAR.
  8. Hey, it was the middle of a war, and slave labour actively sabotaging the production, as you say. It's quite amazing it worked as well as it did. I'm sure the T-model production line was similarly primitive compared to the ones Honda on Chrysler has today. We won't get to the rocketry equivalent of a 2013 car production line if we don't keep at it, and fail considerably along the way. Payloads... well, humans are plentiful. But I must confess I am more interested in bringing stuff back, people can be grown elsewhere. Rune. I've often been accused of looking out too far ahead. But I already gave my opinion on the present state of affairs.
  9. +1. Yeah, uninformed support can be worse for the cause, sometimes. But I stick by Tsiolkovsky's words: "The Earth is the cradle of humanity, but one cannot stay in the cradle forever." Considering how expansive and plague-like our species is, we have little choice anyway. Rune. It might be selfish, but I root for us.
  10. Yeah, I saw that coming while I was writing ^^'. But then I thought, if he can ("...in Human history..."), why not me? As long as I don't mention the Mayflower and pilgrims (I had in mind the Vikings when I mentioned the first Atlantic crossing), I should be OK. Yeah, we are nomads. But first of all, we are curious monkeys: we try stuff to see what happens. As to space being hostile: Duh. But so is 90% of Earth, without technology, to naked primates. And with enough technology, you can literally re-build you favourite place in the middle of the sky. If I leave Earth (and I don't mean me personally, though I would like to), I want to go somewhere better, with a climate I choose, a gravity I choose, and as much room as I choose. If you don't get it yet, I'm talking about free-floating rotating space colonies. So any comment about temperature or surface pressure is irrelevant: I choose those to suit my needs. As to abandoned technologies: you are making my point for me. Yeah, we abandoned blimps, but that is because nowadays we fly in planes, or helicopters. We still fly. Land transportation still happens even if a lot of land vehicles were bad ideas, like nuclear cars (it seems, however, that we are on the verge of electric cars, and if the electricity came from nuclear plants... but I digress). Space tourism is not a technology, it's an idea waiting for the right technology to implement it. So is human expansion beyond Earth. Reusable rockets may be the solution (I personally believe they could bring the cost down by considerably more than an order of magnitude), or they might not be. But then, that just means we have to come up with something else to make it happen. Like using transistors instead of vacuum tubes (or abacus) to perform complicated calculations. And at some point, I have no doubt someone will come up with a material suitable for a space elevator (nothing in physics is against it, and we have promising candidates, even), and then we are set: importing materials to Earth becomes a source of energy, and exporting people something trivial. Rune. Now let's see what other people wrote. This is a popular thread!
  11. Oh, I want to also point out, you folks make a fair amount of valid points about expendable present-day rockets and their inherent limitations. But while you are very right, vacuum tubes also had their own limitations, and we found a way around them to build impossible computers. If I tried, I could find thousands of other examples. And while we are at it, I will also say that I find a moon base to be a big waste of time at the present moment, just like SLS would be (see my feeble attempt to try to get back on topic? ). But we all have our opinions, right? Mine is a bit more informed than some, and less than others. Don't discount any of them until you have analysed them with an open, critical mind. Rune. Who knows? You might learn something or refine your position, I do that all the time, and don't feel ashamed when I do.
  12. I was actually going to rep you for that comment on history (space is most definitely not the Far West, you are right on that), then I kept reading (and this response also sums up some other points made by other people on following posts, not only about what you said). Rockets don't have to be expensive. What is expensive about a rocket? Fuel? The cost of metal? No, what makes them expensive is building them like works of art, in a clean room, with the tightest tolerances in any industry, and by highly skilled aeronautical engineers, and then throw them away after 5 minutes of use. Now study how the V-2 was built, and the launch cadence. You could even trace a reasonable parallel with the mass production of cars. And then you could even look a little bit further, and start thinking outside the box and see that a rocket is not the only way to get something to orbit. The rocket equation may not be going to change, but a space elevator (and this is just an example) could in theory be a fully conservative system, even be used as an energy source. And energy IS cheap, at least right now. Now, there might not be any destinations to go to right now. But neither were any destinations when the first Atlantic crossing was done. Neither was there any reason to leave Africa because of lack of resources. The fact that those things, those motivations, don't exist at the moment, doesn't mean they never will. Rune. Besides living, I want to dream the future into existence too. Sue me.
  13. Hum. I really have to re-post my crafts. My K-22 has the same powerplant (single jet+2 nukes), and I find the thrust issue to get over 10,000m, not on rocket takeover. I actually use the nukes with the jet to get over 15kms quickly (by 7,000 meters you already get upwards of 700s isp on the nukes). But I also light them when I'm close to flameout, and throttle down to 2/3rds to keep the jets going a bit further and build vertical speed quickly. But, my takeover speed is also much, much higher, about 1,500m/s, so I get much more in-space delta-v out of it. What's stopping you from really speeding up? Drag? Too few intakes? Burning all your jet fuel before then because you climb too slowly? Edit: Upon close inspection of the screenshots, I see you don't touch the throttle. Bad idea, you can squeeze quite a bit more out of the jets if you throttle them down a bit after flameout. Rune. Kinda confused.
  14. I have a couple on things waiting on me passing my driving license exam this wednesday and allowing myself to start KSP to actually launch them. I'll post them here ASAP. Rune. If I can stick them on top of a Nova safely, that is.
  15. Really? Well, due to lack of ideas, R-SUV is still the first choice, so you might get lucky, I'm horrible at naming stuff
  16. Just by your description, and without trying out the craft, I think I know what's the problem. On rocket takeover, and with any SSTO really, you want to have a decent ascent speed to get over 35 kms and serious drag losses as soon as you can. So after speeding up at 20-25kms, pitch up until you see about 50m/s on the vertical speed indicator, perhaps lighting the nukes to get an even higher T/W on the pull up maneuver. You can loose an infinite amount of delta-v by staying in atmo. Rune. The second the jets go out, the atmosphere becomes your biggest enemy.
  17. Ok, how about a big supernova relatively close? That fries the whole solar system, never mind Earth. Is that enough of a radical thing? Rune. There are ELE's, and plenty to choose from.
  18. Hey there! I didn't see you, but I think I like you.
  19. That's an easy one to answer: room to grow. A solar system with a few trillion humans will be much more productive in terms of anything you can name, including science, than one with perhaps 10-20 billion at most and zero growth allowed (I won't even get into what kind of society would evolve under such a constrained scenario). Of course, I wouldn't get out of a planet to colonize another, much less a barren rock like the moon, that would be stupid thinking. There is enough stuff in the main belt to build about 300.000 Earth's worth of habitable surface, pick the surface conditions to suit your taste. Never mind using the Oort cloud or the Kuiper belt. Rune. There is a lot of planetary chauvinism going around.
  20. Not if you have some knowledge about how these things work and make it a rod of tungsten with a decent ballistic coefficient (long and pointy). Look at the beginning of thethread to see what percentage of the energy gets dissipated as heat. Then divide by the energy necessary to vaporize each unit of mass of tungsten. Increase mass so final impact mass is the one you want, by perhaps a few of kilograms per delivered ton. Rune. It's called ablative heatshield, and tungsten makes a hell of a good one.
  21. No magnetic anomaly would bring down a plane, or sink a boat. I'm dead certain about that. However, a massive methane buildup and release produced by, say, algae, might (by greatly lowering the density of an area of the sea and the air above it). And in fact, I seem to remember I once read that there is an area somewhere in the pacific where this kind of thing happens relatively often, thus providing a natural explanation to the Bermuda Triangle legends.
  22. Hey! A Hugo award I haven't read! That goes to my "to do" list right away, thanks. And Scotius... well, if the polynesians could do it, then I'm sure we can, without having to wait for new fancy physics. Rune. We have a saying in Spain... "Sobre gustos, no hay nada escrito".
  23. Well, thermodynamics haven't changed since then, so the efficiency of rocket engines is pretty much unchanged. You could shave some weight with our fancy electronics, but that's basically extra peanuts for the astronauts. So with the same fuels and the same number of stages, the rocket would pretty much just as big.
  24. Then I'll hold off on rebuilding my thread until it comes back. I still can't find a decent name for the company, anyhow.
  25. Some screenshots would do wonders to go with those great introductions. I upload the to imgur, but you may have your own preferences. Edit: Ok, never mind that. Apparently I was suffering from a horrible case of network adapter settings, making web pages go at the speed of a paralytic snail, and the images didn't load at all. I'll leave it because I hate empty posts without explanation as to what happened. Rune. And keep at it!
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