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Nibb31

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Everything posted by Nibb31

  1. At the time Apollo was conceived, some people thought that it would be impossible to achieve the level of precision that was required to rendezvous in orbit. It was something that hadn't been proven and therefore couldn't be relied on for the baseline mission profile. Therefore Saturn was to be a precursor to Nova, which was pretty much the "Plan B" if it turned out that orbital rendez-vous was impractical. Gemini proved that RV and docking was possible, which opened up the EOR and LOR profiles, but the Saturn V was well under way by then. It did allow them to abandon Nova.
  2. Anything that hits the ISS from a vertical angle isn't going to be in much of an orbit for long, which means that it wasn't in much of an orbit to begin with.
  3. It's a view looking up inside the F9 upper stage LOX tank with the composite helium tanks.
  4. I'm confused. Are we talking about DreamChaser or some hypthetical F-111/Space Shuttle mashup ? Cargo DreamChaser has foldable stabilizers so that it can fit inside a fairing (It actually stole the idea from the Russian Spiral). It needs to be in a fairing because it carries unpressurized cargo palettes on the outside. After the fairing is jettisoned, the stabilizers unfold. There is no reason for them to ever fold back during flight, so it probably uses some sort of reliable one-way spring and latch mechanism (like most other space-deployable solar panels, antennas, and landing gear). Crew DreamChaser, if it ever flies, will have fixed stabilizers, because it doesn't launch inside a fairing. It doesn't have a fairing because it needs to be able to abort surely and rapidly, so you want to minimize any unnecessary jettison and unfolding events that only introduce extra points of failure.
  5. The jet engines were for ferry flights on one of the Buran prototypes. They were never intended to be present during reentry. How would that work ? Folding back the stabilizers would provide less lift.
  6. They fold on Cargo Dream Chaser because it launches inside a fairing. The Crew version (if it ever flies) should have fixed stabilizers, because no fairing, because of launch aborts. I don't see why it would need to retract them in flight, so it probably can't. Misland ? It doesn't have propulsion. If you switch runways while you're still high enough, you can glide there.
  7. Not sure what you mean. Capsules are also lifting bodies. The only difference is that they use RCS for control instead of control surfaces. Operationally, DreamChaser is a capsule with a slightly higher L/D ratio and a lot of extra weight due to the wings stabilizers, landing gear, and hydraulics, which are only used during the last minutes of its mission (which is primarily to fly in space). In practice, the Space Shuttle experienced around 3G deceleration. Due to the lower surface area, DC will probably come in a bit hotter, say 3.5G. Soyuz goes up to 5G for a short period. A modern lifting body capsule should peak at around 4-4.5G coming in from LEO. Another advantage of a capsule is that it can re-enter passively if necessary. If it loses control authority, it will stabilise into a passive attitude, you will get more Gs that way, but as long as you can pop the chutes manually and you don't get eaten by lions, you should survive. From LEO at least. If a lifting body loses hydraulics or power, you're toast. Lower Gs are preferable of course, but the difference isn't huge and the mass and complexity penalty is high.
  8. It doesn't have wings. It's a lifting body with stabilizers.
  9. Are you a qualified aerospace technician or do you have any experience with aerospace maintenance ? Have you got any experience that is similar to the listed tasks ? (Apparently you don't know what SAP is, so that's a negative point). My guess is that if you don't have a diploma or the experience, then you won't qualify.
  10. It's not destroyed, it is "disassembled" part by part by the protomolecule...
  11. That's one hell of a tool. - Oy, Bob, pass me the main body tool! - Alright Tom, you want the 9m or the 12m one ?
  12. Looks like that accident was mostly due to not aviating (the co-pilot disconnecting a vital system and not realizing the consequences) and then miscommunication between the crew. Yelling "MAYDAY" over the radio would have served no purpose. As opposed to yelling "MAYDAY", which was my point. No distress signal was sent, because the crew was probably busy trying to recover from the stall.
  13. The 3 rules for a pilot are: Aviate: Keep the plane flying (or landing). Navigate: Know where you are, figure out where you're going. Communicate: First with your co-pilot and crew. Note that Communicate comes last, and even then, the priority is to communicate with those who are able to actually help you Aviate and Navigate. In an emergency, a pilot should concentrate on the flying. You only communicate when you have the plane under control and you know where you are. Once you have time to actually Communicate, the last thing you want to do is to scream "MAYDAY" over the radio. That serves absolutely zero purpose. It's much more useful to calmly state your emergency, your cockpit readings, and your position.
  14. Where did you see any serious plans to use the X-37B to dock to the ISS ?
  15. That's not very useful compared to the penalties in mass, cost, and complexity. What's a "military X1 shuttle" ?
  16. That's because the goals were stupid. Which is why I claim that it was a bad idea. A winged spacecraft is a bad idea. Sidemount launch is a bad idea. Cargo and crew on the same vehicle is a bad idea. Building a 100-ton launcher that can only launch 20-tons is a bad idea. Focusing on the LEO instead of going back to the Moon was a bad idea. And even reusability was a bad idea at that point. The whole concept was flawed from the start. NASA did the best they could with what they were given.
  17. Actually, IMO, it was quite the opposite: Terrible idea, impressive execution. And I wouldn't call it a failure either. It flew for 30 years and accomplished most of its goals. Remember that we are talking about 1970's technology. Most of the Space Shuttle was still designed with a slide rule. There was very little CAD engineering in those days. Crippen and Young had balls of steel to climb into that thing for its first flight. It was the most complex machine ever designed and yet it flew. When it did fail, it was more because of bad decisions and cutting corners than poor engineering. Yes, it had flaws, but the flaws were mainly due to the fundamental concept than the execution of that concept.
  18. How many threads does there need to be for talking about the Space Shuttle and Buran ?
  19. I never understood the appeal of Bethesda games regarding graphics. Skyrim and Fallout 4 both suck unless you mod them like crazy. I thing GTA V, despite getting a bit old now, it's still among the most beautiful games graphics wise,and remember it was originally designed to run on the old Xbox360. I can't wait to see Red Dead Redemption 2.
  20. The "mirror universe" populated by "evil twins" of our beloved heroes goes way back to TOS. I don't give a hoot about canon. All I want is a good story. Star Trek is riddled with lazy plot devices (holodecks, replicators, parallel universes, time travel, alternate timelines...) that only exist so that lazy writers can throw canon out of the window whenever it suits the story and the filming budget for the current episode. The Expanse on the other hand is great space opera, with decent physics, consistent characters, and a good story. It does have a couple of plot holes, but at least they do their best to avoid most of the silliness of Star Trek.
  21. In fact, there are references in Star Trek lore that claim that the Terran Empire existed in the mirror universe centuries before Star Trek Enterprise. In the mirror universe, Burnham is raised by Georgiou instead of Sarek, which means that it diverges at least before Burnham's birth, which means that although the universe follows different timelines, Burnham's biological parents, who had different personalities and lived different lives, still managed to have sex at the exact same moment and conceived the exact same individual with the exact same genes and gave her the exact same name. It makes no sense. Other example: Mirror-universe Burnham is presumed dead. What happens if prime-universe Burnham now has a child ? We end up with people who exist in one universe and not in the other. After a few generations, these divergences will cascade and you end up with totally different populations in both universes and the "evil twins" plot device falls apart. This is what I hate about Star Trek. There are so many parallel universe, alternate timelines, and time travel plot devices that just about anything is possible and the writers don't have to adhere to any kind of rules. It's just stuff that's made up as they go along to make easy plot tricks.
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