[CydeWeys]

An airplane isn't a rocket. New Origins is clearly a rocket, not an airplane. Your comment is waaaaaaay off base. The most salient difference here is that a rocket propels itself forward by using the exhaust gases from burning its fuel as the reaction mass, whereas an airplane uses surrounding air as its reaction mass. New Shepherd can generate thrust just fine in a vacuum (because it's a rocket), whereas an airplane isn't going anywhere.

> There are probably two orders of magnitude in complexity between making a reusable sub-orbital, and a reusable orbital rocket.

Hardly. They've already built all of the necessary control systems, and had multiple successful test flights. Now they just need to scale them up. Admittedly this is not trivial, and I'd put SpaceX as far ahead for this reason alone, but it's definitely not an order of magnitude more difficult, probably just around twice as difficult. And nowhere close to two orders of magnitude!

[vkou]

My point is that scaling up from sub-orbital to orbital is extremely hard. It's not that far removed from going from airplane to rocket, in terms of complexity.

You're going from having a top speed of Mach 3 to a speed of Mach 27 (Stage separation and max Q at Mach 6 and 5). You're shaving every conceivable weight-adder. You're dealing with a rocket the size of a skyscraper, which crumples in on itself when not filled with fuel.

This isn't AWS, where you scale your app by spinning up a couple new nodes. The difference from a suborbital hop to orbit is increasing your delta-v budget nine-fold.

[anovikov]

Well, not it isn't. Their current rocket must have a delta-v of about 2.5km/s, so we are speaking of about 3.5-4x increase. Yet, that's a lot.

But remember their current rocket uses hydrolox. That isn't an easy fuel mix to work with! Russians for example, still haven't managed it.

[greglindahl]

Wait, Blue Origin has already built all the necessary control systems for flight regimes that their existing rocket can't reach? Hypersonic retroburns are not much like ballistic trajectories that barely touch the edge of space.