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Comment by kolinko | Hacker News Reader

It wouldn’t help much, sadly. Getting to orbit is about speed, not height — you need 27000 kph to get to orbit, and having an air launched platform would shave off 1k kph off it at most, perhaps 5k with some insane hypersonic engineering.

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Main advantage of air launch is that you can better match your target inclination or perhaps even orbit timing - just drop the rocket at the right time in the right direction over the ocean. With a fixed launch site you always need to adjust for some difference of your point of origin versus the orbit you want to achieve.

Sure but the main disadvantage that you need another highly complex vehicle. Best case its a existing commercial platform like Virgin Orbit, but then you are limited by the size. Or you design another whole vehicle that more complex then the rocket itself.

And even then you need to have all the infrastructure flying and integrated rather as nice static pad.

You are also putting human in bigger danger unless you want to have another autonomous highly complex vehicle.

The benefits are simply better addressed by having 2-3 launch pads.

How big a trebuchet would be needed to chuck a cubesat directly into LEO?

cubesat + small rocket. Orbital mechanics require a burn at a later time in the orbit, to avoid coming back to say hello again to Mr. Trebuchet (Ignoring Earth's rotation)

100 or 200 km tall at point of release ought to do it.

The tip would still have to be doing 7 km/s.

Lookup SpinLaunch.

It helps a bit more than you imply, though: if you can launch from a higher altitude, you have less atmosphere to plow through. That lets you use more of your propellant to speed up instead of to push air out of the way.

You've just got the problem of building a fixed wing aircraft which can carry your rocket full of explosive propellant, successfully release it pointing in the right direction and then get the hell out of the way....

You're extremely limited by the amount of mass you can even launch from a mothership aircraft.

There's no future in this idea outside of small sat, and probably not even there.

That isn’t very helpful considering rocket launches only spend a few seconds in atmosphere mostly going vertically to get above the majority as quickly as possible .

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