SpinLaunch

[ysabetwordsmith]

It's like a round railgun! It throws satellites into orbit, or is intended to. It's a work in progress.

"The more crazy the project is, the better off you are just working on it — rather than talking about it."
-- JONATHAN YANEY

Absolutely, totally true. "To know, to will, to dare, and to keep silent." All the more important in today's overly connected socially networked blabberfest.

Just remember: you cannot  use this type of system to launch anything delicate.  The spin and thrust will mangle fragile cargo.  What you can  use it for is mass cargo.  Metal parts, food ingredients, anything that is solid or granular.  Maybe liquid if you have really great containment, but that's riskier.  This tech would be fantastically useful for building and supplying things in space.  But throw the raw materials, and build it up there.

Also, dudes: put one on the Moon!  It'll be way easier and cheaper to launch from there, and some of what's on the Moon is also useful for building things in space.  Nobody's built anything to do  stuff on the Moon yet: you could be famous.

Comments

[siliconshaman]

I believe it's being called the YEET! launcher...informally of course. But yes, the principle designer says it would work better on the Moon.. no need for a vacuum containment system for a start, and only 1/6 gee to contended with.

Well, we're going to be building lunar colonies before 2040, and that's a fairly simple self contained launch system that requires no fuel, and since it's all electric it'll run off solar power happily enough.

With that, the lunar colony can start paying it's way pretty quickly. Lots cheaper launching aluminium from the lunar surface to build stuff in orbit. The savings would make a lunar colony financially viable.

Yes ...

[ysabetwordsmith]

That's what I thought. I've seen space and lunar development kick off enough times to recognize the steps. But this time, they skipped one! Usually people make a linear railgun first. They're pretty easy. But they take miles of land and rail, which runs up the cost. This is cheaper because it's tiny in comparison.

Re: Yes ...

[siliconshaman]

Yup.. proving that the trebuchet is superior. (because that's what it is, a flywheel trebuchet.)

Re: Yes ...

[ysabetwordsmith]

Okay, yeah, if I imagine an arm on the thing, now I can see it. And I remember guys trying to figure out how to make an armless trebuchet for battering walls, but they usually couldn't figure out an effective release mechanism and all I could tell them was, "Yeah, it's possible, but I don't remember how."

Re: Yes ...

[siliconshaman]

Oh is that all... Ok. Picture the rocks placed on the flywheel (rocks plural because it has to balance. Although it can be a a rock, singular and a water filled barrel to act as a counterweight because then you can adjust the counterweight.)

Now, what holds it in place is something that looks like a shelf, or scoop made of three sides and back, that cradles the rock. The outside of the scoop hingles down, like the tailgate of a cart, but it's held in place by latch... and the latch is held in place by a leaf-spring.

So, the flywheel spins up, the spring comes under tension, until eventually it's no longer able to hold the latch back, which releases the slide, and the rock goes thataway. Of course it's bit more complicated, you need a threaded nut&bolt to pretension the spring so it releases at the right point...

Which is probably why there's no record of them beyond a few scribbles in artisans notebooks. It's possible, and in theory it would be more powerful, given the right motive force and pulley set up. But it's also incredibly finicky to aim and unreliable unless you've got the tech to make it out of metal...at which point you're better off making cannons.

In fact, I'm not certain that you can make an accurate and reliable version until you're at our current level of tech... at which point, you're not flinging rocks. (at least not at castle walls)

Also dudes: put one on the moon!

[(Anonymous)]

Drawback: you'll lose Cheyenne mountain. ('The Moon is a Harsh Mistress'- Robert Heinlein)

Flavia
(bv97045)

[dewline]

There is also a need for delivery of delicate cargo and we need something else for that service.

But for bulk transport? This will be good and useful.

[siliconshaman]

Well, a really loooong liner accelerator could get your payload up to speed with minimal gee forces involved, and while having one as long as Florida on Earth isn't viable.. real estate on the Moon is a bit cheaper and comes with less environmental issues.

But what about...

[ng_moonmoth]

The concept put me in mind as similar in some ways to Verne's cannon: load the necessary amount of kinetic energy into the projectile while on the ground, except not with high explosives. But there were three points I wonder about that I didn't see any discussion of.

First, one has to get the projectile out of the vacuum chamber. I sort of get the feeling that the projectile drops out of a trapdoor in the flywheel, so it doesn't have to battle air rushing in to get into its free-falling trajectory. But it would be nice to know more about that.

Second, the projectile is coming out at several times the speed of sound, which is going to create one helluva shockwave. Yes, there's a lot of more or less empty land out in NM, but sonic booms get around and break windows when they do. Wnat are the neighbors gonna think?

Finally, in addition to the energy dissipated by the shockwave, there will be quite a lot of atmospheric friction. That not only will represent more energy loss, but will do a dandy job of heating up the projectile. Sure hope that heat doesn't get back to the rocket fuel tanks... let alone a space station asking for a chunk of steel and getting a blob of molten metal.

It would be interesting to know how they're intending to deal with the issues of physics and politics around these items.

Yeah, set it up on the Moon and all those problems go away. Paging Mr. Harriman ... Mr. D.D. Harriman!