Rockets being passé, China is working on using an electromagnetic railgun to launch crewed spacecraft the size of a Boeing 737, weighing 50 tonnes, into orbit. This remarkably ambitious project is even more ambitious than it seems at first glance.
The article states the company in question is only trying to achieve somewhere between Mach 1.6 and Mach 5. It will need a rail miles long, but more importantly the bulk of the velocity change needed to get to orbit will come from rockets.
It takes 9-10 km/s of delta-V in a real world scenario to get to low earth orbit. That’s about Mach 27 or so, a long ways away from Mach 1.6 or even Mach 5.
While railguns are known for rapidly accelerating projectiles to hypersonic speeds over the short length of a gun barrel, there's no limit on how slowly they can accelerate something or how long the "rail" part of the railgun can be. Accelerating "slowly" over a long distance is totally possible!
It just seems like an engineering improbability to me with the tolerances required. 5+ miles, I guess you could bury part of it to reduce things like wind, but still.
That would put the g-forces back in play: the faster you go around the rail the stronger the centripetal force that keeps you going in a circle. If the rail is straight the force only depends on acceleration not speed.
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