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mikegarrison

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Everything posted by mikegarrison

  1. I flew in a circle around that. In a 737. We were in the area doing a test, and the pilot decided he wanted to fly around the crater a few times at low altitude (VFR). So he did. We all went to the side of the airplane and looked out the windows. This was before 9/11. ATC is less keen on letting airliners just fly around at low altitude in VFR these days.
  2. The second burn is implied when you reach the target. If you just do a fly-by, there is no second burn.
  3. I have been having a lot of trouble with the "advanced transfer". It just doesn't seem to be as reliable as it used to be. Sometimes works, sometimes gives wonky answers. However, I love the new more general two-burn transfer planner compared to the old in-plane Hohman planner.
  4. Space toilets have long been one of the really difficult parts of human life support to get working well. The new ISS toilet sent up last year supposedly cost $23M to develop and build. Side note: I worked with a guy who was part of the development process for a new toilet in airplanes. If you are old enough you probably remember airplane toilets that were basically big buckets full of human waste and that blue chemical, and if they got full then they got full. (It was not widely advertised, but that blue chemical was actually recirculated. So when you flushed with it by the end of the flight, it was not *just* blue chemical....) Well, when we switched to vacuum lavs, that went away. Our toilets now all connect to a central tank, which is kept at a pressure lower than the cabin pressure. So a person uses the toilet and presses the lever. A valve opens up and the pressure differential sucks the material away to the tank. You never get individual toilets that fill up (although you could get the entire system to fill up). Anyway, I worked in the noise group, and the guy I worked with was trying to measure the noise the toilet would make when it flushed. We wanted enough suction to suck things, but not so much it was scary to the user. To test these in the lab, they apparently used a mixture of liquid (just water, I think) and fake turds. They were made of something like peanut butter and dried dog food and some other ingredients that when mixed together and shaped into logs had the expected consistency, stickiness, and other mechanical properties.
  5. Not for enough money. It's the golden rule. I'm sure that for enough money you could hire SpaceX to not only launch you up there but to send up a waiter who fed you grapes whenever you felt like it. Mainly what SpaceX did with this mission was defuse (a little bit) the "billionaires in space" pushback, by sending up a crew of people who mostly didn't actually pay to go (and also had sick kids cheering for them).
  6. Yup. I was going to post this, but you already did.
  7. It does seem that her Twitter stalker was attacking her for being not sufficient complementary (i.e. "a hater") of Musk and SpaceX. But most often people who stalk women on Twitter mainly do so because they are women. Whatever they use as their excuse for it is usually only of secondary importance.
  8. She apparently has a harassing Twitter stalker, but that's sadly not at all unusual for women.
  9. I got curious about this and looked up her name and her twitter feed. I saw nothing unusual or objectionable.
  10. The Atlantic article is dead on, in at least one respect. The biggest issue is "risk normalization". That's essentially what got BOTH space shuttles. They knew they had problems with the o-rings and the foam, but the more times it happened without a catastrophe, the more they decided it was just normal.
  11. I hate that phrase, because it misses the crucial element. Aviation safety works because it's not about BLAME. It's about ROOT CAUSES. So many people don't understand this. Politicians especially love to find someone to blame. The idea is that if you look for causes, rather than looking to assign blame, you can find things that are useful to fix going forward. If you just want to find someone to blame, all you end up doing is punishing people for actions in the past. It's not nearly as effective. That's not to say there is never any blame to found, but a search for blame tends to make people to hide things. A search for causes tends to make people show things.
  12. 15 miles per hour is about the speed you would hit the water from a 2.3 meter fall. So if you have ever jumped off of a 3 meter (10-ft) diving board, you have hit the water faster than that. But when people dive (or jump) into the water, they try not to land flat ("belly flop"). Going in long-wise means a slower deceleration. You go further under the water, but you don't hit as hard. These capsules can't do that, so it's more like belly-flopping into the water.
  13. I tried using this a while back, and it worked OK, except there was some kind of conflict with the "terrain scattering" (those fake rocks, trees, etc.). Has that been resolved? I don't see any mention in the FAQ. OK, never mind. I just found my old post, and it was actually a Kopernicus bug. Is Kopernicus required?
  14. It works differently if they have given you a free loaner car. All of a sudden, they get a lot more motivated to finish the work and get their car back.
  15. I don't know. I read through the part about the tank testing, and it said nothing about any 10% failure rate. But it was talking about pressure testing every flight article (which is entirely reasonable).
  16. I can't understand anybody arguing this. I can tell you that we pressure test every single airplane before we let it go up for a first flight. And if 10% failed, not only would heads be rolling, but we probably wouldn't be in business anymore. There is just no way you can build something like this and only be 90% sure it can even hold pressure, but then argue that it is able to be launched, landed, refueled, and launched again. =========== We don't really test them because we expect anything to "fail". Instead, we're looking for the leak rate, to make sure it doesn't leak faster than we expect. (A certain amount of leakage is not only expected but designed in.) And as a side note to the side note, if you are onboard during a ground pressurization test you can't go flying immediately after. You have to be careful, because you can actually get "the bends" from that.
  17. And it they had, I would have been fine with it.
  18. Another quote from this document: W. T. F. It's crazy to compare this one plant to the GHG emissions of the ENTIRE USA, and then argue that means it's not significant. I don't know how usual or unusual it is to have a statement like this in the EA, but it's a frigging useless standard to meet -- comparing one operation to the entire US output of GHG. By this standard *anything* is going to be insignificant.
  19. Um .. what?! 10% failure rate is not something most manufacturing companies would associate with "an insane amount of confidence". That would be, in fact, shockingly bad. I will give SpaceX the benefit of the doubt here and assume this is just a scoping thing along the lines of "even if we had a 10% rate of failure, the environmental impact would be ...".
  20. OK, but one thing to understand is that especially at low TRLs, things can fail. Not just "take a lot of time and money to make it happen", but outright fail. There can be problems we haven't found yet that simply prevent this great idea from actually working.
  21. What do you mean by "current technology", anyway? Arguably an Orion ship is within our current technology, but it's still at a very low TRL. https://en.wikipedia.org/wiki/Technology_readiness_level If you mean "TRL 9" -- technology that we have actually already used in service -- then it's pretty clear that Mars is a huge stretch. Anything beyond that simply requires life support technology we've never had to develop. We're talking mission durations in years or decades.
  22. "Made full use" of a window? Is that just "looked out of it", or is there a more full use that I'm not aware of?
  23. What do they teach kids these days, anyway? Cows jump OVER the Moon.
  24. "Crewed" is just a more inclusive word than "manned". It's not a job description.
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