But is it really a catapult? - eviltoast

Using centripetal force puts it in trebuchet territory does it not?

  • Tar_Alcaran@sh.itjust.works
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    2 months ago

    Ignoring air resistance (which you really shouldn’t, especially not when you’re talking in the thousands of meters per second), you need to launch something at around 1400m/s get it to 100km high “suborbital”. You need to launch it over 8000m/s to get it into orbit. In 2022, Spinlaunch were getting to ~450m/s, but that was two years ago and maybe they’ve improved.

    Now, 1400m/s is in the neighborhood of a tank cannon, which is doable. But 8000m/s on the surface, or about 29.000 kph, is about mach 23. That’s like running smack into a brick wall of air, every millisecond. And in reality, you need MUCH more speed, because you’re shooting at a much shallower angle, so there’s a lot more air to get through.

    • itsame@lemmy.world
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      6 days ago

      The animation shows they use a normal(?) engine once the rocket is launched. Looks like this can always work, it is like throwing a rocket into the air and then starting the engine. I wonder if that is any better than normal launch or from underneath an airplane.

    • threelonmusketeers@sh.itjust.works
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      2 months ago

      I think they’re too early. Kinetic launchers will be great for yeeting raw materials from moons and asteroids, but launching delicate satellites through Earth’s thick atmosphere seems fraught with challenges.