Any plausible non chemical rocket based space launch system on Earth?

[GTOM]

I write an sf story, and an important part is an attack on a big, expensive space launch system on Earth.
But what system could be built without pretty much magic? Looks like space elevator couldnt be made even from carbon nanotubes.
Maybe a space cannon, that could launch cargo to space with suborbital speed, then lifted further with nanotube cables and a space station below GEO orbit?

 

[.Scott]

Perhaps "SpinLaunch", which is cargo-only.
Also, if you are looking to avoid "big, expensive", then a space elevator wouldn't fit the bill.
There is also "Air-launch-to-Orbit".

This paper describes a proposed 120-foot super-sonic jet carrying a SpaceX Falcon 1 for launch to orbit. For comparison, the Concorde SST was about 200 feet long.

 

[phyzguy]

It's a story. Just say there was a breakthrough in high strength materials that made the space elevator possible.

 

[Filip Larsen]

Depending on how "feasible" the launch system must be, it may be quite tricky to come up with a system that doesn't use chemical rockets.
One option could of course be a nuclear SSTO, if such will fly with your story universe.
Or perhaps some kind of air breather (meaning chemical jet propulsion rather than chemical rocket) to bring the cargo high into the atmosphere and then something like a skyhook to lift it into orbit, but even then both the skyhook and the orbital cargo would require additional momentum change and there are only so many ways you can that while in orbit. For instance, circularizing cargo orbit from a sub-orbital injection trajectory is not super feasible to do with electric rockets.

 

[DaveC426913]

Sorry, what's wrong with the Beanstalk (space elevator)? It's not happening now, but do you really think it's a dead-end?

OK, what about a skyhook then?

 

[GTOM]

Perhaps "SpinLaunch", which is cargo-only.
Also, if you are looking to avoid "big, expensive", then a space elevator wouldn't fit the bill.
There is also "Air-launch-to-Orbit".

This paper describes a proposed 120-foot super-sonic jet carrying a SpaceX Falcon 1 for launch to orbit. For comparison, the Concorde SST was about 200 feet long.

It describes a rocket in the stratosphere phase. Could it really withstand such big acceleration?

 

[GTOM]

Sorry, what's wrong with the Beanstalk (space elevator)? It's not happening now, but do you really think it's a dead-end?

OK, what about a skyhook then?

i dont want to bring some sort of unobtanium to explain how it can hold the weight. the structure should be still ruinable without nukes.

 

[.Scott]

By "It", I am guessing you mean the SpinLaunch system ... And by "it", I am guessing you mean the SpinLaunch second stage.
Yes, a second stage rocket can be designed to withstand the 10,000Gs inflicted by a SpinLaunch launch.