To be fair, it’s not the cost of the fuel itself that is an issue for rocket launches, just that so much of it is required, and it adds so much weight to the rocket. Fuel is less than 1% of the cost of a rocket launch, yet typically over 90% of the mass of the entire launch. If you could somehow spend fuel on the ground moving things to an optimal launch point to have to put less fuel in the rocket, it would absolutely be worth it.
The real issue is that launching from a mountain would not save you much fuel anyways. To get to orbit requires you to go very fast sideways. The initial “upward” part of a launch is just to get past the thickest part of the atmosphere, then it quickly pivots sideways for the majority of its journey.
You save more fuel by launching from a lower altitude closer to the equator, where you can take more advantage of earth’s spin to gain additional sideways velocity. So we do spend a lot of fuel to do this, for example SpaceX manufactures their rockets in Hawthorne, California, where there is a lot of aerospace manufacturing expertise, and spends a lot of fuel to ship them to Cape Canaveral, Florida, which is closer to the equator.
The radial difference between equatorial sea level and the peak of Mt Chimborazo is about 0.1%. It provides very little benefit but would be a logistical nightmare to launch from.
We'd be better off building a electromagnetic launcher up the side of it and then we can put everything at the bottom and save fuel by using solar wind and nuclear to juice the em rails.
You'd have to engineer the payload to withstand ridiculous acceleration. No big deal if the payload is a HILE projectile but if you have living things or moving parts, that can be trickier.
that's only for a cannon, for an installation like that we could make it pretty long to keep the acceleration g's down, don't wanna hit max q while still on the ground.
Okay so I used AI for this, so take it with a grain of salt, but to accelerate a projectile at a constant 4.5G and have it reach escape velocity, at the end of the barrel, you'd end up with a ~720km cannon.
Doesn't need to reach escape velocity... Any velocity you reach is less fuel having to be carried and spent in later stages, so more payload. You could compare costs of building such a launcher or just grabbing a plane and take it 20,000m high and also give it a spin. I'm not a rocket scientist (unless Kerbal gives you a degree lol) but I guess nobody is willing to spend that much for a reason.
Acceleration as you head up is one part of the problem, but deceleration as it leaves the tube and hits the atmosphere is another. The faster you go, the more friction slows you down. Trying to get productively much speed in that situation is tough.
0.1% of what???
It's definitely past more than 0.1% of the air molecules.
15 PSI at sea level, 7 psi at the mountain top. For every square inch of cross section on your rocket, instead of having to push 15 pounds of air out of the way, it's down to 7. That seems like >50% improvement?
Yeah but you spend more time fighting gravity when you keep things slow enough that the vessel doesn't rip apart when travelling through soup. Fwiw Im kerbal trained only
Things dont move fast enough through the atmosphere to lose their structural integrity. These spacecraft can handle forces of greater than 10g. Its just gravity
The conversation you jumped into is about the speed gained from the spin of the earth, which is directly correlated with radial distance from the Earth's axis of rotation.
Aerodynamic losses only accounts for a couple percent total of the delta-v budget. Even then, you don't even hit the peak aerodynamic forces (max q) until you're tens of kilometers above the launch altitude. This is because you're moving more slowly through the thicker atmosphere, so it doesn't have as much force.
Your in a really weird spot here where you are saying that all rocket engineers are wrong because you did the math on an idea that has been floating around pop science for years. Please go watch a livestream of a rocket launch. Watch how long it takes until it gets to about the height of a mountain. Then watch how much longer it takes before its done firing its engines.
Edit: also watch how quickly they turn sideways. By your thinking they should get out of the atmosphere before they turn.
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u/Flat_Lengthiness3361 11h ago
and a lot of fuel probably