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Nibb31

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Everything posted by Nibb31

  1. Nibb31
    Does this stupidity really need yet another thread ?
  2. Nibb31
    Yes, fly-by-wire sets up all sorts of limits to prevent the aircraft from exceeding the airframe's flight envelope.
  3. Nibb31
    So I guess you won't be buying an iPhone 6 Plus. Oh and: (which is actually wrong, it's $859 for 16GB storage and 1GB RAM, whereas the OnePlus One has 64Gb and 3GB RAM)
  4. Nibb31
    Not in today's world where everything is outsourced. Most large companies these days outsource their IT and HR departments.
  5. Nibb31
    If you're mixing manned and unmanned, you're missing Cygnus and also probably Shuttle and Buran... Voskhod and TKS are missing too...
  6. Nibb31
    To make you think about it.
  7. Nibb31
    A Space Shuttle modified to use NTRs would no longer be space shuttle. If you had NTRs, you would design a ship around them, not the opposite.
  8. Nibb31
    If your heatshield is toast, no amount of retro firing will save you (unless you are loaded with 8000m/s of delta v). This is also one of the reasons why Dragon and CST-100 are safer than DreamChaser. Their heatshields are safely protected from MMOD damage right up until the last minute.
  9. Nibb31
    The only problem is getting the full 1000 ton external tank to orbit...
  10. Nibb31
    So if Boeing wins a contract it has to be because of corruption and arm twisting and absolutely can't be because their proposal was technically better than the competition?
  11. Nibb31
    Have you actually seen what a capsule looks like after reentry ? It certainly won't be "fill her up and fly her again". The first returned capsules will have to be torn down for post-mission analysis work to determine if they can be reused, and since there are only 6 flights in 3 years, it's not really enough to build the confidence in reusability and not worth the cost of establishing the recertification procedures. I suspect that the capsules will be gutted or stored for later use, like the current Cargo Dragons. The actual systems will probably be refurbished and reused, but the "airframe" and skin will be new for each flight. It's not like they actually need a fast turnaround either.
  12. Nibb31
    Also, it's not like reusability provides much of an advantage when there are only 6 flights planned.
  13. Nibb31
    Luckily for us, NASA doesn't choose its vehicles based on looks. And actually, the CST-100 is far from cramped. It's the roomiest of the three vehicles and is wider than Apollo. It's been known for months that it would be a downselect to two suppliers. Boeing carries the heritage of Mercury, Gemini, the Apollo CSM, the Saturn V, the X-15, the X-37B, and the Space Shuttle, as well as the P51 Mustang, the XB70, the B1 Lancer, the 707, the DC-3... How more inspiring can it get? It employs some of the best engineers in the World and its experience allowed its proposal to match NASA's criteria more closely than others, which is what really matters. Also DreamChaser is built by Lockheed Martin, which isn't exactly your typical "new space" company, and the proposal included ULA's Atlas V. Again, based on looks only. CST-100 is just as exciting as DreamChaser. I really don't get this irrational bias towards esthetics over functionality. Even the World's best designers knox that form follows function and not the opposite.
  14. Nibb31
    Not sure what that means or how it makes Dragon any different from the CST-100. In the same way a 787 Dreamliner is just a modern iteration of the 707. It uses the same basic layout, the same old jet engines, the same wings and fuselage... Boring! Or in the same way a new Porsche 911 is just a modern iteration of the old VW Beetle, same 4 wheels, same 2 doors, same steering wheel, same rear-mounted engine... Nothing new or innovative there either! The architecture of a vehicle is the result of evolution: we try various architectures and shapes and we innovate within the layout that works best. We've tried biplanes and seaplanes, we've tried 3-wheeled cars or six-wheeled cars, and we've tried winged spacecraft, and those simply weren't practical designs. In a few decades, we will look back at the Space Shuttle and it will look like the Zeppelins of the 1930's, the Concorde, or the 1961 Chevy Corvair, all things that seemed like a good idea at the time, but turned out being technological dead-ends. How is CST an inferior design when you don't know the criteria that NASA used to rank each of the competitors? A superior design is the one that best meets the requirements. Evidently NASA considers that the two selected proposals were superior, otherwise they would have made a different choice. It's not about offending Boeing, it's about picking the most credible competitor. Boeing has met all its milestones. SNC has not. Boeing has a solid and reliable design. SNC has not. There was serious risk associated with SNC's proposal, including the fact that they were about to switch engines, which is a major redesign that pretty much cancels the milestones that they did achieve, and that its abort scenarios were less convincing, making it harder to certify. We also don't know the price of SNC's bid. It might have been on par with Boeing, which makes the choice a no-brainer. CST lands on land with airbags, has a pusher escape system, and it can reboost the station if necessary. That's all pretty innovative. And so are most its systems, avionics, propulsion, which are all state of the art or brand new systems. If anything, DreamChaser is less innovative since it's pretty much the old HL20 that was designed by NASA 20 years ago.
  15. Nibb31
    The money awarded is what was asked for in their bid. Space X said they could meet requirements for $2.6 billion so that's what they got. Boeing said they could do it for $4.5 billion so that's what they got. We don't know how much money SNC asked for, maybe they were actually more expensive than Boeing.
  16. Nibb31
    People keep on using "but ... crossrange!!!" and "but ... lower Gs!!!" as if they were huge advantages of DreamChaser compared to other vehicles. Well, it turns out that NASA is not interested in crossrange or lower Gs. Those things were not part of their requirements. And on the other hand, DreamChaser has some serious shortcomings that were much more troubling: DCs hybrid engines were the same that are causing the delays on Virgin's SpaceShipTwo. They are running into severe development roadblocks and changing the engines at this stage in the design process is a major redesign, which would put the program at risk and require new certification and new milestones. And of course, there is the problem of aborts at low speeds. A lifting body requires high speeds to "glide", and when it does glide, it doesn't fly like a plane. Its controllability and survivability during all stages of an abort pose a lot of questions that haven't been convincingly answered.
  17. Nibb31
    I don't get this "moving back" thing. Capsules are pretty much the best form factor for a spacecraft, just like "four wheels-front engine" is the common architecture for cars for over a century, or "fuselage and wings on the side and tail at the back" is the best layout we've found for aircraft. We have tried other arrangements, but in the end, we pick what works. By that logic, a Porsche Cayenne is a step back from a Robin Reliant, because it uses the same layout as a Ford Model T. Winged spacecraft look cool but they have all sorts of problems. Capsules just work well. They are not a step back.
  18. Nibb31
    Dragon V2 and CST-100 are pretty diverse already. One lands on rockets, the other lands on airbags. One flies on Atlas V, the other flies on a Falcon 9. One is reusable, the other isn't. I don't see why SNC's proposal would have been more "diverse". I don't even think that "diversity" was among NASA's goals. They had selection criteria, and those two proposals were the ones that best met those criteria.
  19. Nibb31
    What is the step back here?
  20. Nibb31
    At least we now know how much NASA is going to pay for a Dragon V2 launch: $2.6 billion for 6 flights, that's $400 million, or $100 million per seat. So much for "cheap access to space". Also, with 6 flights for each contractor between 2017 and 2024, it's easy to understand why reusability wasn't a requirement.
  21. Nibb31
    Coolness wasn't a requirement. They had milestones and requirements. DreamChaser failed to meet those milestones and requirements. It's not a surprise.
  22. Nibb31
    I thought that was mostly for electrical engineering. Tada tssss...
  23. Nibb31
    It's not that it's not allowed. It's just that it's not very relevant and just looks a bit random next to other posts about career counseling, Kerbals vs Grox, or Finnish folklore. It's just not the sort of place where you should expect people to take your post seriously. I didn't even know what a Samsung 840 was before I read that you were talking about a model of SSD. I'm pretty sure there must be forums specifically for people who are looking for information about SSDs. There might be a couple of people here who understand (and care) about your topic, whereas on a PC hardware forum, you will probably get more support and more on-topic discussion than on a forum that is specifically about "off-duty chatter".
  24. Nibb31
    I really hope that "coolness" and "amazing looks" were not the top criteria in the competition.
  25. Nibb31
    Is there really such thing as a "rocket scientist" any more? If you want to build rockets these days, you would seek a job in aerospace engineering.
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