Perhaps they could simultaneously release a counterweight downward into a large pool of water connected to several channels designed to distribute the kinetic energy. As long as they designed the device so the same mechanism released both payloads then it shouldn’t be too tricky to time it right.
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And he (Gerald Bull) got assassinated for his efforts. Frank Langella played him in the made for HBO movie.
Maybe the forces aren’t that big. WWII anti-aircraft guns used proximity fuses to detonate the shells when they got as close as they could to the target. These used valve circuits, and yet survived 400g (?) and got to a similar height as that thing.
My main worry is the energy in the launcher. The HARP gun might have been more efficient than a rocket because all the fuel was converted to kinetic energy on the ground. Here, the rotor arm has high more kinetic energy than the projectile, and they are just wasting that when it stops to load another one.
This could work in space. If you put one of these on a rubble asteroid, it could divert it by firing off rocks. But one on the earth’s surface won’t do diddly IMHO.
How come no-one ever puts megabucks into our smart ideas? No fair!
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It’s definitely around 10,000 lateral g’s when the thing is spinning at full speed. That’s what Spinlaunch itself is claiming and that’s just how the math works for centripetal force with something that radius spinning that speed.
I haven’t seen the exact specs on the motor but it’s been described as “a couple of megawatts applied over 1-1/2 hours.” If that means something on the order of 3000 or 4000 kWh of energy (or even ten times that) that’s minuscule in the grand scheme of things, especially if the electric power comes from a renewable source. There are long-range Teslas with 100kWh battery packs, so think of charging up something like 40 of those.
I have no idea how much energy the vacuum plant requires to suck all the air out of the large launch chamber though. That might be even more than what it takes to spin up the system.
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Space! Space! Space! Ele! Ele! Ele! Vators! Vators! Vators!
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Ah. Quite right. I had forgot the steady acceleration just to get the thing to go in a circle. I find it surprising that it is that much greater than the acceleration along a gun barrel; in which case, this idea just got even sillier. There were schemes for firing stacks of intelligent mirrors out to the first Lagrange point to counter solar warming. These could have survived a gun launch, and might have survived a centtrepetal launch. Water bears might even enjoy the ride. But not much else.
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10,000Gs is their number, and I assume they did the math on all this before starting the company.
The difference between “going high” and “orbit” is enormous energy. Suborbital is frankly easy. Balloons can do it. Orbital means escape velocity, which is a whole other order of magnitude. There have been a hundred concepts over the decades for things that could go suborbital and thus laypeople thought it only needs to go a little further to reach orbit, but that’s not how orbit works. It’s about speed, not height. There’s a reason we’re still using rockets to do this after 70 years, and it’s not from lack of trying other options.
But none of that means this won’t work. I wish them all the best!
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Probably the best argument against a space elevator (assuming we were able to build one) is “what happens when it inevitably comes down due to engineering failure or space debris impact or act of terrorism or just age and neglect?”
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I think that is answered in the Mars Trilogy.
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Thanks. As someone else pointed out, I hadn’t reckoned on the acceleration needed to just go in a circle before you let go. I, too, would love to see some nice, clean way of getting stuff into orbit. I still favour accelerating in a straight line. A plasma canon might be a good solution: that gets beyond the energy density limits of conventional chemistry but may be less cranky than rail guns ( which my autocorrect just edited to ‘fail guns’ 
)
PS: An old friend of mine ran his company from Bermuda, and sent me a picture of HARP, which was a walk from their hotel. He had never heard of it.
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That does seem the simplest option. It is likely still a challenge to release them in such tight co-ordination that there is not a huge shock to to the rotor. - the speeds and energies involved kind of blow normal mechanical engineering intuition away. Speaking of which, that water impact would be like a bomb going off!
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I could see this as a method to launch some of the components needed to assemble a spacecraft or station in orbit. Or fuel.
OK this is kind of a tangent since it obviously wouldn’t work here but what would happen to a human in a neutral buoyancy tank if the entire tank was accelerated to high G-forces? Would they eventually get crushed by the increased water pressure or no?
Perhaps if they have Abyss-like breathable liquid ?- (article mentions 20g threshold where liquid fill is required to prevent lung collapse - still is a long way from 10k-g).
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AIUI, increase the g by a factor of n, then you increase the weight of the column of air or liquid by n, which increases the pressure by n. So one atmosphere at 1g is normal sea level pressure: double g and you double the pressure, so you’d not only be twice as heavy yourself, but you’d be under 2 atmospheres of pressure. Under normal conditions, that’s the pressure at 10m (~33 feet) depth underwater. 10kg would mean 10,000 atmospheres of pressure. For reference, the bottom of the Mariana Trench would be about 1100 atmospheres.
Even if you weren’t instantly crushed, even if you had The Abyss style breathable water, the instant that pressure was released, every gas in your body would expand and you’d explode from the bends.
0/10, not recommended.
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Yep. There is no time to decompress - you go straight from enormous G to zero the moment you were released. Your density is not uniform, so your heavy bits will have separated out. Not good for those of us with delicate complexions.
I am not saying this can’t work. They claim they can launch unmodified mobile phone circuits. But IMHO, a gun of some sort looks a better bet.
Beam 'em up Scotty!.
In an article I read about it they mentioned booster rockets on the projectile itself eventually. They also mentioned interest from the defense sector. I have this feeling that the anticipated end project will slowly change over time to be something dismally different, and far more destructive.
I imagine platforms of these in orbit, pointing downward.
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