China Uses Giant Rail Gun to Shoot Smart Bomb Nine Miles Into the Sky
China Uses Giant Rail Gun to Shoot Smart Bomb Nine Miles Into the Sky
China's navy has apparently tested out its hypersonic rail gun — but during a demonstration of its power, things didn't go quite as planned.
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Successful or not, news of the test is a pretty big deal given that it was just a few months ago that reports emerged about China's other proposed super-powered rail gun, which is intended to send astronauts on a Boeing 737-size ship into space (NASA had begun building its own astronaut-shooting railgun in the 1990s, but had to abandon it due to lack of dinero.)
I thought EM-powered launching of fragile things like people was thrown out decades ago. How do you fire something up at high Gs without having high Gs? Projectiles and even some cargo may not care, but people might.
You can launch people out of a mass driver.
They'll die, but you can do it.
If by people you mean "people-flavored slurry", sure.
We here at Terminal Velocity Aerospace prefer the term "post human product".
There's an amazing novel series called The Hyperion Cantos where they have these space ships that accelerate so quickly they turn the passengers into goo. Then over the course of the trip the auto-doc regrows the people. Their memories are wiped, so they aren't aware of what is happening to them.
In theory you can launch humans magnetically if you have a really long acceleration track, though I don't think "gun" is really a very good description of such a facility since it's more like a maglev (or hyperloop style vacuum tube train) that gradually rises miles into the air with one end open. Technically possible, but given the costs and difficulty with getting a tall enough structure I'd be fairly skeptical that China actually intends to seriously build one.
Wouldn't have to go straight up, could go along the ground then have a long sweep that turns up
That was actually the best idea because a long enough length and curve means you can use less acceleration each second. One problem is that to keep it low, like say 3Gs, both the length and curve are huge. Like hundreds of miles. Second is the exit - how high would you have to built it to not open the vacuum tube (it has to be a vacuum to work, i.e. the issues that Hyperloop ran into) and be slamming the projectile with a deceleration effect into the thin air that's left? The numbers have been crunched before, mass drivers on Earth can't deliver breakable things.
Also, that curve would be additional Gs and a lot of technical problems to maintain its path.
Thats what I was thinking of, you still have to deal with building a hugely tall structure though, because the exit must be above the thickest part of the atmosphere
Most or all of it. To be at orbital velocity the projectile would be moving at 30 km/s. Even a small amount of gases would be a like a brick wall.
Hugely tall and extremely rigid, because if it wobbles while the projectile is moving through it, it will tear itself apart.
Now someone much smarter than I can do the math, but over a long enough distance with a shallow enough incline on a ramp I dont see why it couldnt be done.
The math might mean the scale of the ramp makes the idea completely unrealistic to build. But I dont see why it wouldnt work.
Physics joined the chat
What does that even mean? Yes, this is a question of physics.
8 gs is enough to cause most to pass out. 40 gs is usually going to cause permanent injury. Accelerating on a ramp at less than 40 gs would take a while if you want to reach escape velocity which is like Mach 25. Just mental mathing poorly, it’d be like a mile or two of railgun. Iunno, someone sober do the math.
Well yeah a lot of the concepts for magnetic accelerators for orbital launches in the past 50 odd years have required 2+ km of ramps to work well
Mathematically it's possible, like you mentioned. But due to physical restrictions of our planet it might not be feasible
Well for one you cannot make anything orbit with only a launch from the earth, it will require at least an orbital insertion burn or it will either crash back down or reach escape velocity, not orbit earth. So is there another rail gun in space that catches and relaunches the craft? Are they firing rocket engines and rocket fuel with this rail gun?
Physics, specifically orbital mechanics, remains in the chat.
The shallower your incline is, the more air you have to fight through post-launch to get to orbit, during which you're losing velocity. And to get into low-earth orbit you have to reach 28000 kph (17000 mph) because it's not so much about going up as it is about going really fast.
So you need to leave the end of the gun going fast enough to lose speed to air resistance and still reach and maintain orbit. I haven't attempted the math, but it seems like your vehicle would burst into flame going that speed in the atmosphere.
You still haven't accounted for how an orbital insertion would work. You have to reach orbital speeds in the correct direction which requires a directional burn not possible from the ground.
Ok, so how does the orbital insertion burn work then? Are they rail gunning rocket engines and fuel up there too?
Re-read the comment. "Physics has entered the chat" Its neither a yes or a no that its possible.
Im sure you could accellerate a person gradually enough over a long enough distance in a sufficient vehicle to launch them into space. Wether its practical or if we have the tech yet isnt "physics"...
Re-read the comment. "in space" is not the same as "in a usable orbit"
Inertial dampeners
Yea that’s just bullshit