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  1. I think Ariane would have been chosen even if SX/Falcon9/Heavy was an option at the time. It is a long standing European tradition to insist that European funding be piped back to European industries no matter how much cheaper everybody else does it.
  2. Because it is (Amphibious Assault) Ship. I.e. the amphibious part refers to the assault, not the ship itself. The ship is needed to make the assault swim. The boots, tracks and tires the ship vomits at the beach then make the assault crawl. Sometimes the bigger ships don't go to the beach itself, but instead drop smaller ships from their rear ends that proceed to the beach to vomit out the boots etc. The biggest ships can also throw off helicopters that fly to the beach or even farther inland and drop the boots onto the ground. Some even use only helicopters. It is a whole ecosystem out there, with various niches and specialized species of Amphibious Assault Ships to fill those niches! But the assault is always amphibious, because it comes from the sea and goes to the land.
  3. Alternatively the arm and weight could be shaped so that the arm will clear the weight regardless of timing. As we have all three dimensions to work with this should be possible. I think the practical solution could be to split the counterweight into two, one on each side of the counterarm, and placed far enough from the arm itself that distance between the weights will remain more than the payload end mechanisms can safely pass between. For the gun system, I have a vague idea that I just cannot refine, so I'll just drop it here in case someone more knowledgeable might take interest and break apart. I am thinking of a single chamber gun, but not loaded with a truly explosive charge. Instead the grain in the chamber would be not entirely unlike the grain in a solid fuel rocket. Burning slow enough to keep the acceleration on the payload manageable but providing enough gas to keep the pressure up long enough for the payload to reach the maximum velocity attainable. I wonder if such a system might work even on a theoretical basis.
  4. Although... maybe the actual threat is not a bespoke Starship spy satellite, but the excess capacity on any Starship launch? Any Starship zipping about replacing broken Starlink satellites with new or repaired units could carry a hidden secondary camera payload of substantial size. How would you time a SSBN movement to avoid potential spy sats when there is a potential spy sat overhead at all times? Even though you might not quite cram an entire KH-11 into the Starship unnoticed, very valuable intelligence could be collected by lesser devices if they can catch those most secretive of maneuvers out of the blue. Of course the number of earth imaging satellites has exploded and even cube sat sized units can provide surprisingly good resolution these days, so in a way there are potential spy sats overhead at all times already. A determined state could avert those by spending money, though, as in buying imagery from said satellites at the time and some other place than the operation they seek to hide. It is the non-commercial satellites that are most troublesome.
  5. You think many injectors on single chamber is silly? At one point von Braun's team planned to use six chambers on one nozzle for the A10! Presumably each chamber with a silly number of injectors.
  6. I'll also throw in the AMaRV or Advanced Maneuverable Re-entry Vehicle. It was a nuclear warhead the USAF developed in the seventies and flight tested at the turn of the eighties but never fielded. It used flaps not entirely unlike KSP airbrakes to pull hairpin turns at hypersonic speeds.
  7. 1. In hydrogen bombs the heat and pressure necessary to start fusion is reached with a small fission device. So no. There is also the intermediate level of boosted fission device, where a small amount of fusionable material injected into the fission core provides a significant boost to the energy output. 2. Depends on the exact technology level, namely how difficult it is to reconfigure the guidance system, but not very much. You may lose some range or be limited to longer flight times as the airframe may not be strong enough to fly the optimal trajectory. Specifically for the M-V rocket, though, it has been suspected to be easily weaponized. 3. @DDE gave a much better answer above than I ever could.
  8. On the other hand if the rover broke down before you dropped the carousel you would lose all the samples. Just goes to show how unrealistic the entire "sample now, collect later" strategy is, I guess.
  9. The civilian GPS signal used to be artificially noisy to limit the accuracy. This was called "selective availability." They have turned it off now because augmentation methods and other GNSS systems have made it ineffective plus a lot of civil and merchant activities have become dependent on accurate location. To my knowledge the capability still exist even in the newest satellites. But for example my cell phone's navigation chip picks up (at least) GPS, GLONASS, Galileo and Beidou satellites. The app I check this with lists a couple more systems and has a category for unknown satellites too. So fiddling with just your own system's output may turn out to be ineffective as a drone protection. For the curious this also is (one way) how the russian GPS spoofing that's been in the news every once in a while works. They drown out the satellites' transmission with their own that causes the calculated position to drift off the real position. Careful calculation should allow them to control how much and where the drift is at least in a limited target area. Less predictable effects will happen outside the target area, of course. Countermeasures include encrypted transmissions that the malicious party cannot create (GPS at least has these), directional antennas that reject the spoofing signal coming from low elevation and listening to a lot of satellites and rejecting the outliers whose transmission suggest a position far from the others.
  10. Try thrust vectoring when your nozzle is affixed to the skin of the space craft. Well, vanes or propellant injection would still work, but there must be a good reason why most TVC capable motors go for the moving nozzle system.
  11. Perhaps it could if done by selective breeding only as that process dates back to prehistoric times. Direct genetic manipulation certainly wouldn't be primitive at least by today's standards. What would be considered primitive at the time there are colonies on other planets that would consider themselves to be primitive is up to anyone's imagination.
  12. Is it really necessary for the biological part to travel to space? I say use something like coral animals or maybe insects that have been bred and/or genetically manipulated to grow into specific shapes and make their exoskeletons out of something suitable for the purpose. So take one shed starshipbeetle shell and install a few raptorcoral husks at the bottom. Okay, for the control computer you might need something living. Dogs are known to learn many tricks so pick a breed for a starting point. Make sure there is a well protected place in the ship for the - quite literally - ship's brain to sit in. Then just go play fetch with asteroids or something!
  13. Maintenance costs mostly, I should think, especially with podded propulsors. The complex angle gearings required for mechanical ones can be quite hard to get to for servicing. I have also seen lesser space requirements mentioned, as there is no need for big shafts running from the engines to the gearboxes and propellers. Oh, and electric transmission completely decouples number of screws from the number of engines. Power splitting and combining gearboxes are very specialized things and can be hard to maintain or even get right in the first place. (See Freedom-class combining gearbox issues.) The technology has advanced by several magnitudes since the eighties, don't even mention the sixties experimental SSNs let alone the battleship era systems. As mentioned complete electronic propulsion systems from engine to propeller/wheel are now commercially available off the self and with both wide and long service history. Very high power semiconductors appear to have been the key to efficient and reliable electric propulsion. In the submarine context there is also another consideration. Without mechanical links between the turbine and the propulsor the designers gain extra freedom in designing the frequency characteristics of each end. Not to mention reduced vibrating mass means less radiated noise overall, and the space gains leave room for additional quieting measures. Very very very important for an SSBN.
  14. The wonderful people of Project Rho have put a frighteningly large amount of though into exactly this. In short, mortgages, part payments and group buys would not be only possible, but downright required for private people to buy even the cheapest of starships. The other side of the coin is that you can use those to drive your story/plot to specific directions i.e. a trader failing to generate enough profit to pay off the debt may turn into piracy. Anyway, here's the link to the relevant page: http://www.projectrho.com/public_html/rocket/starshipowner.php Have fun!
  15. Newer US submarines have their reactor cores built to last for the entire lifetime of the submarine. That will be 30 to 50 years at current estimates with just the original fuel load. Unless the NTR is the only power source on your spaceship it can be run for a considerably lesser fraction of the ship's operational life than a submarine's, which (abnormal situations aside) is only shut down while pierside and on shore power. Therefore I would expect that other systems on the space ship would start to expire long before the reactor core dies. Of course such a long life reactor cores require fuel refined to a very high purity. While I have no knowledge I suspect it could be considered "bomb-grade" even. This constrasts with the French who are determined to use the same civilian grade fuel their nuclear power plants burn. Thus they have to refuel their submarines (and the only non-US nuclear powered aircraft carrier in the world) every ten years or less. So if politics restrict the purity of fuel used, refueling the NTR may become an issue to be solved.
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