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Nibb31

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  1. Nibb31
    Thanks, I know how to use google too. It's more a matter of properly introducing a discussion instead of "Random subject, discuss".
  2. Nibb31
    You might want to explain what it is before asking the question.
  3. Nibb31
    DragonLab was supposed to be a cheap way for corporations to experiment with microgravity R&D, and maybe even small scale manufacturing. It might also have been a way to refurbish those CRS Dragons that are piling up in a warehouse. You could probably fly it for less than $100 million (NASA pays $133 million for each CRS mission). The problem is that industry simply doesn't seem to be interested in those space-manufacturing applications after all.
  4. Nibb31
    DragonLab has been a commercial offering for over 5 years now. No customers have shown any interest yet, not even NASA. It's quite possible that RedDragon might follow the same path.
  5. Nibb31
    SpaceX isn't a space program with unlimited funds. Their business model is to sell launch services to customers who pay for them. There is only one customer buying Dragon 2 flights, and it's NASA. They have committed to 6 to 10 manned Dragon flights, and that's it. After that, the ISS is splashed and there are no destinations for Dragon in LEO (unless Bigelow finds some magical customers too). That isn't going to change soon. Even if SpaceX offers rides to Mars, they still need to find customers who are willing to pay to send stuff to Mars. The MCT is vaporware at this point, and there is no business model for a Mars colony. The rest is pure speculation.
  6. Nibb31
    They will be "mass-producing" 6 Dragon 2s. Maybe even less if they get to reuse them.
  7. Nibb31
    Depends how you design your equipment bay. You could have a clamshell design that opens, docks, and closes. Ever seen James Bond ?
  8. Nibb31
    If they were dropping 20 Dragon 2s on Mars, that's at least twice the number of Dragon 2s they are going to be flying for NASA. They would be better off designing a whole new purpose-built mass-produced disposable lander bus for 20 Mars missions rather than modifying a reusable crew taxi that is only going to fly half a dozen times.
  9. Nibb31
    And how are ion-powered robots and a reeling line easier to develop than a robotic arm ? It doesn't need to be reeled in anyway, it has an IDS docking adapter. Again none of that exists. It would cost billions to develop for no good purpose.
  10. Nibb31
    Because inflatable heat shields don't exist. The closest is the HIAD, which isn't a heatshield, but a decelerator (like a big inflatable parachute that works in the upper atmosphere), and more to the point, doesn't work very well (yet?). The only way to bring back Hubble with current technology would be to build a huge Orion/Dragon capsule, with a cargo bay, a manipulator arm and the biggest parachutes ever made by mankind. You think developing Orion was expensive ?
  11. Nibb31
    If he had an ejection seat, probably, but you can't really jump out of a hypersonic capsule. Once the parachute failure became apparent, it was a matter of seconds. The backup plan was a manually operated reserve parachute, but that one failed too. The landing rockets fired after the crash, causing a fire that incinerating the wreckage.
  12. Nibb31
    Not really. Those were just paper studies for a mission. NASA's main focus was on the Shuttle program, which didn't even have a docking port or an airlock at this stage.
  13. Nibb31
    No, that's the price for a F9 launch. FH is supposed to be $90 million. This makes them about 50% cheaper than the competition. I doubt reuse will bring the prices down significantly, even if it does reduce costs for SpaceX. They are already the cheapest shop in town, with an increasing backlog. Cutting prices even more will only make the backlog longer and won't increase profit, and they are going to need a lot of profit if they want to fund their grandiose plans.
  14. Nibb31
    Saving Skylab was always a bit of a low-priority side project. It had supplies for another mission, but it really wasn't designed for long life. They expected that the interior would be invaded by bacteria and mould by the time the Shuttle went to visit, so it might not have remained habitable. They also needed to design a docking module for the Shuttle and an airlock because Apollo and Shuttle used different air pressures and compositions, as well as systems for resupplying water and fluids.
  15. Nibb31
    NASA policy was always to wear spacesuits during mission-critical events (burns and reentry). During Apollo, they wore the "fishbowl" inner-helmets. Only during the early Shuttle missions, the crew had those disco-blue suits and unpressurized clam-shell helmets. These were dropped after Challenger, when the orange LES suits were introduced, followed by the ACES suits. The Russians had cosmonauts flying without spacesuits in Voskhod-1 (there was no room for them to wear suits), which was super-dangerous, but they wanted to beat NASA with a multi-crew flight, and of course, Soyuz-1. After that, space suits have been mandatory.
  16. Nibb31
    They don't always announce when they give stuff up... They usually just lose focus and move on to something else. They aren't actively developing their constellation any more either, after all the hype about it being the cash cow that will fund Mars colonies. There might be a couple of guys still working on crossfeed, constellation, or reusable upper stages, but they seem to just transfer resources onto Musk's next pet project until the old one dies.
  17. Nibb31
    My father was a kid in the London East End during the Blitz bombings. He used to sneak out of the shelters to watch the "doodlebugs" (the nickname for the V1). One day, when they returned home from a wedding, they found the house burning because a German bomb had gone right through my father's bedroom. If it wasn't for the wedding, he would have been sleeping in his cot. My great grandfather was killed in Belgium during WWI. Although we have an old letter from one of his mates saying that it was in a heroic action to take a fort, we'll probably never know about the actual circumstances. Many of the "heroic actions" from WWI were desperate attempts to overwhelm the enemy's machine guns with more cannon fodder. He was probably sacrificed like millions of other poor blokes like him.
  18. Nibb31
    Especially Voskhod. It was considered a death trap, even by the Russian cosmonauts, which is why it only flew manned twice.
  19. Nibb31
    The Polyus payload is still rather secretive and was part of the Soviet response to Reagan's SDI ("Star Wars"). The lasers were designed to destroy US SDI satellites. The Polyus spacecraft was mounted upside down on the Energia rocket, so it was supposed to rotate 180° after separation to circularize its orbit, but due to a software bug, it rotated 180° twice and deorbited itself. Typical Kerbal error.
  20. Nibb31
    A sphere is the most efficient ratio between volume and mass, which was the most important criteria for early space craft. The closer you are to a sphere, the lighter your capsule is for a given volume. If your capsule is light, it needs lighter parachutes. On the other hand, a sphere is not passively stable in the airflow, so it will tend to tumble. You can counter this by ballasting the weight on the bottom so that it remains upright. It will also have practically no lift, so your trajectory will be purely ballistic, which gets you a very high-g descent. A conical configuration, on the other hand, is inherently stable and provides lift. You can direct the blunt end towards the flow and tilt the capsule to obtain lift. A short cone shape (like Apollo or Orion) can be oriented more obliquely towards the airflow than than a taller cone (like Dragon), which means that you can get more lift. Lift provides a more gentler reentry and more cross-range.
  21. Nibb31
    It's not about being on-time. It's about being faster than anything that has ever been done in the space industry. And SpaceX doesn't exactly have a great track record of being on-time or even staying focused on any specific project.
  22. Nibb31
    Unpressurized cargo is only for use outside the ISS.
  23. Nibb31
    Yes, if it flies empty with the trunk at max payload, which would be a bit of a waste, but is possible if they really need to send up a 3-ton piece of unpressurized equipment. How would you even get unpressurized cargo out of the Dragon cabin at the ISS ? Currently, the trunk walls act as a radiator. That won't possible once on the ground. The trunk with the fins doesn't fit inside a payload fairing, which we have established, is going to be a requirement for planetary protection. Planetary protection is more of a process/quality/certification thing, but it requires development of ground systems, clean rooms and procedures that SpaceX probably doesn't have to deal with in its current payload processing facilities. Power systems are part of the spacecraft, not the payload.
  24. Nibb31
    Nobody ever intended to send people to Mars in a Dragon. It isn't designed for that.
  25. Nibb31
    Dragon's unpressurized cargo requirement for COTS is for the trunk. It isn't designed to fly unpressurized cargo inside. How would you get it out ? Yes, it can survive a contingency depressurization event, but that doesn't mean that all systems are currently hardened for long duration exposure to vacuum. Unless you add radiators, there is no way to dispense the heat generated by the onboard systems. It will need new navigation and communication systems, new power systems, a new trunk, provisions for planetary protection, an automated hatch, a mechanism to deploy whatever it has to deploy. That is a substantial redesign already. Yes, only if you look at the outer mold line. It will be as much a production Dragon as a NASCAR Ford Mustang is a production Ford Mustang. Dragon has never intended to be EVA capable.
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