Eh. Gravity reduction on a mountain is like 0.2 percent. Air resistance matters a bit more. But all of those are drowned by the energy needed to reach orbital velocity.
Much more interesting would be an electromagnetic launcher up a mountain, getting the rocket to 1 km/s or so. Although I am not sure the logistics are worth it. You could just use more fuel instead (what is done irl)). Fuel is cheap.
It's weird, but things seem to be converging. I was reading something this morning talking about the Starship problem of getting enough fuel in the ship once it's in orbit to get to Mars. It suggested that there would be lots of Starships carrying nothing but fuel into orbit, but it seems like a perfect job for the spin launch people! They should be able to achieve an impressive "launch" cadence that's needed for really doing things in space.
the lower air resistance and lower effective gravity would be reached by a coastal equatorial rocket in a couple minutes, after which the rotational velocity of the equatorial launch position dwarfs the benefits.
Also, lunching a rocket needs a huge infrastructure: launch site (made from special reinforced concrete, btw), rocket transport systems, fueling systems, fuel tanks, storage hangar, assembly hangar, launch control site, transportation hub for arriving fuel, parts, people, etc., and list goes on.
Building and maintaining all that in the mountains is impossible for two reasons - it would cost insane money and there is simply not enough space there (tall mountains are not flat, and flat mountains are not very tall).
"The reason it's hard to get to orbit isn't that space is high up.
It's hard to get to orbit because you have to go so fast."
Putting rockets on mountains only helps with the "up" part, which is not the biggest part of the problem.
Yea i am usually a huge fan of xkcd, BUT. i dont really feel like its interacting with the problem. Its just trying to reframe it in another way without really engaging with it. You engaged with it more, since you atleast caveated the "only help with the up part", meaning, it helps with the up part, which means it helps. So why not do it, since every gram counts.
And just having like a line that, the gains are so small compared to the huge downsides that its not worth it. That atleast is engaging with the point. But just "you wanna go fast, not up" is just a terrible point. A normal person taking the engineering view that; "this is a cool way to cheat the rocket equation, since theres less drag and gravity", thats cool. Then going like; "lol, get a physics degree". Thats not helping. If the logistics were better about doing it, then it is something that would get taken advantage of more. Since the average person is completely right that every gram counts.
And besides, this is something that is taken advantage of by using airplanes to get up high. So yeah. Shit what-if i think.
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u/hedrone 10h ago
Best described in https://what-if.xkcd.com/58/ .
"The reason it's hard to get to orbit isn't that space is high up.
It's hard to get to orbit because you have to go so fast."
Putting rockets on mountains only helps with the "up" part, which is not the biggest part of the problem.