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Everything posted by mikegarrison

  1. https://en.wikipedia.org/wiki/Sealab_2021 (By the way, when I was a kid, Sealab 2020 seemed set in the remote future. So was Space 1999 and 2001 A Space Odyssey.)
  2. That was actually an important design consideration for the https://en.wikipedia.org/wiki/Lockheed_Constellation, which was designed with a triple stabilizer because they wanted to make sure it would fit into the hangers of the primary customer. A single vertical stabilizer would have been too tall and would have required new hangers. Not if you lose an engine.
  3. Vertical stabilizers and rudders are actually sized by engine-out conditions (on most multi-engine airplanes). The asymmetric thrust is a bigger deal than basic yaw stability and control. Anyway, as @sevenperforce just said, it's mainly about lever arms. The farther away from the aerodynamic center for yaw, the smaller you can make them and still get the same control. Vertical stabilizers don't usually have a significant amount of steady-state lift-induced drag (because ideally they are trimmed to a zero-lift condition), but they still have form drag and friction drag and wave drag. So the smaller the better, usually.
  4. Already borrowed. I first saw it in one of Douglas Adams's Hitchhiker Guide books. Although, IIRC, it was in a guide entry about a triple-breasted sex worker. Or maybe that was "the best bang since the big one"? I would have to dig up my paperback copy of the novel to be sure.
  5. I think that's a very old patch. I remember trying it before the pandemic.
  6. I would argue that the first "footprints" on Mars have already been made by robots.
  7. Besides, after a while everybody goes crazy and starts gene-splicing and killing each other with electricity that shoots from their hands. Just ask Andrew Ryan.
  8. What they really need is to just put a ladder on the side of the Dragon and have one of the astronauts climb it while bumping their head on something. That's an infallible drive system that doesn't even require any fuel.
  9. It's nearly the same problem that the Starliner had. That dinitrogen tetroxide is nasty stuff and corrosive AF. It doesn't play nicely with valves. SpaceX eventually got rid of the check valves by putting in burst panels, IIRC, so that really I think they have no way of shutting off the SuperDracos, much less restarting them. They are kind of one-time-use items.
  10. https://www.theonion.com/nasa-panics-after-asteroid-fires-back-1849587289
  11. It's not viable, for lots and lots of reasons. Just for example: on a commercial airplane you have to demonstrate (with a real evacuation using real people) that you can evacuate the entire airplane in 90 seconds -- in the dark, with half the exits blocked off (and they won't tell you which half until the 90 seconds starts). I've never seen anyone from SpaceX ever address anything like this.
  12. That's understandable. I kind of expect a fair number of explosions, actually, although I guess we'll see what happens.
  13. Lunar Starship is not designed for Earth re-entry.
  14. 15Gs does not necessarily mean they would have passed out. Whether you lose consciousness depends on how long you are subject to the loads, how hard they are, how you are restrained, and what direction they are in. (And if you are a pilot or a scientist or an engineer or a tourist?) Most climbing gear is rated to about 18Gs, on the supposition that a person in a harness who takes more than an 18G falling load will likely sustain fatal internal injuries anyway. But that's from the harness -- a person in a couch can take higher loads for a short time. Airplane seats (and pretty much all other cabin furnishings) are rated to 16Gs, based on evidence that 16G crashes are survivable for seatbelted passengers.
  15. OK, so a little Googling says that there was indeed a proposed "Outer Planets - Solar Probe" project (aka. the "Ice and Fire" mission). And yes, the solar probe part of it eventually led to the proposal that finally ended up being the Parker Solar Probe.
  16. I think that same XKCD is what first brought KSP to my attention as well. I think I had heard of it before but only in the context of "little green men trying to get to space" or something, which made it sound more like a tycoon management game. But that comic intrigued me.
  17. That sort of free-return also takes longer. Not a good thing when we are talking about life support and radiation exposure. Anyway, the point is that they were not worried about which way the moon was rotating. The moon only rotates once per month (as opposed to the Earth's one per day), so it's not a big deal.
  18. Yes, they went around the moon retrograde. This was so they would have a "free return trajectory" in case anything went wrong (and on Apollo 13, it did). If you go around the moon in a prograde manner, if you don't brake into orbit you will probably get gravity boosted into a higher orbit. But if you go around in a retrograde manner, you get the opposite effect. So the point was that if for some reason they were not able to brake into lunar orbit, they would automatically end up heading back to Earth for re-entry.
  19. Doubt it. Nertea's mods tend to all work as a system, and Kerbalism is mostly incompatible with that system.
  20. Technically it can can/will/must land even with all three chutes out of service. It's just not going to be a good landing.
  21. I don't know the exact crash load of landing without the retrorockets, but I'm very confident it's more like a minor car crash than an instantly fatal event.
  22. I am pretty confident that the landing retrorockets are not a life/death failure point. Not like, say, the parachutes are.
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