High Thrust propulsion

[ikrase]

Are there any high thrust (i.e. could some day allow Earth takeoff) rockets other than chemical, NTR, NSWR, and Orion?

 

[Artlav]

Sure, fusion, nuclear lightbulb, compressed air, MITEE, antimatter, metastable fuels, maybe some more.

 

[tori]

Elevators, mass drivers, launch loops, ...

 

[Kaito]

Potato, Onion, Carrot...wait what?
However in orbiter, they are all the same

 

[T.Neo]

Sure, fusion, nuclear lightbulb, compressed air, MITEE, antimatter, metastable fuels, maybe some more.

Wait, compressed air? I think you're going to get a pretty bad ISP with that...

Not sure about antimatter though. I think it would be more suited to relativistic acceleration than surface-to-orbit liftoff.

Elevators, mass drivers, launch loops, ...

Elevators are mostly nonsense. They only deliver to a limited orbit and their maintainance and construction can be troublesome.

Mass drivers have to punch through the atmosphere. They would be better suited to an airless body, such as the Moon.

However in orbiter, they are all the same

Indeed, but having an engine with a near infinite ISP and thrust coming out of a two-inch nozzle could be considered unethical by some.

 

[tori]

Re compressed air: I was doing some measurements with a K size cylinder with compressed air at (if I recall correctly) around 2000 psi and the exhaust velocity came out to around 100 m/s, which is around 10 s of Isp. Piss poor, but indeed high thrust, high enough to lift itself

Elevators and mass drivers in atmosphere are of course utter nonsense. Although that doesn't seem to be an issue if you got cash.

 

[Sky Captain]

Re compressed air: I was doing some measurements with a K size cylinder with compressed air at (if I recall correctly) around 2000 psi and the exhaust velocity came out to around 100 m/s, which is around 10 s of Isp. Piss poor, but indeed high thrust, high enough to lift itself

At least theoretically if your air cylinder is made of some super strong unobtainium containing ridiculous pressure it should be possible to exceed exhaust velocity of conventional LH2/LOX burning engine.

 

[ikrase]

Lightbulb is an NTR.

Is fusion even supposed to have high thrust?

 

[Andy44]

Nuclear lightbulb is not a conventional NTR. It gets about 3000s ISP vs. 1000s ISP for a conventional solid-core NTR. "NTR" makes people think of NERVA, so I think a nuclear lightbulb gets its own category. Call it EGC-NTR, for enclosed gas core.

Fusion doesn't exist, but if it did, why not high thrust? Depends on how you contain the fusion reaction and how much power you can deliver to the propellant.

 

[ikrase]

Well, it has containment and pilot power problems.