Good luck to all those involved in the industry!

Although I wish the general economic situation (at present – and even more in the future, which will be worse) was better for them.

JP: in a different context, a nice line from the latest Ian M Banks novel “I can’t wait for this to achieve escape velocity from the mundanity well”.

John W hit the nail on the head. I wonder how many of today’s student protesters have a clue as to what “escape velocity” is.

Just fly!

I’m bored here.

The biggest problem is getting them to re-enter, which is an issue of having ‘just enough’ shielding in just the right places. Elon thinks it could take 2-3 years to get to where this can be done, and admits it is very hard: no one has ever attempted this with a liquid fueled stage before.

Now, as to Morton Thiokol… yes they are a private company, but they are getting their sales through forcing their product on us rather than on its merits. If some private operator wants to buy their product and take an ISS delivery contract, then fine. But that is not even close to what is going on here.

To put the debate going on between the free market space types and the socialist space types in perspective, the Orion capsule has cost $4.5B tax payer dollars already and is not ready to fly. It is a less capable space craft than Dragon. It is not capable of a re-entry on a Mars free return trajectory. I believe this is about an order of magnitude more than the entire SpaceX program to date.

I would also point out that there is no serious player in the commercial space market considering solid engines. The hybrid engines on SpaceShipTwo are not solids; they use a liquid oxidizer and may bet throttled and shut down. Once you light an ATK SRB, you are going where it is going unless you blow the end caps with the “thrust termination system’ or fire an escape tower to pull you away from it. That’s just not acceptable in the commercial world.

I’m pleasantly surprised that the Falcon Stage 1 *isn’t* LOX-LH; I agree, that makes its like a bit more staightforward, but there’s still the matter of checking for Frank-Reed loops on recovered Stage 1s, which could lead to fractures on subsequent launches.

Lest we forget, Morton Thiokol is a private company.

If the excellent folk at SpaceX have a handle on materials (or materials testing) which alleviates this risk, then I’m happy.

And thanks for the play-by-play, Dale. Much appreciated.

As to the re-use of liquid engines. This is not a problem. Even the bleeding edge ISP-Ubber-Alles SSME’s on the shuttle were usable on many flights. The Merlin’s are built to be rugged and use LOX-RP, a much easier environment to deal with than LOX-LH. If you are worried about re-use of rocket engines… well, some of our readers happen to build engines that restart first time every time. XCOR builds the Ronson Cigarette Lighter of rocket engines. The guys at SpaceX aren’t doing too shabby a job either

Governments research projects push the outer edge ‘because they can afford it’. Commercial entities look for the economic sweet spot instead. Wider margins means more trouble free operational hours.

Having mis-spent my youth doing more Physics than was strictly good for me (especially materials, or “condensed matter” as they call it, these days) – I do wonder about the concept of re-using liquid-fuelled first stages, though – given the extreme conditions of temperature and stress such items go through, I wonder how the costs of testing a recovered stage match up to the costs of building a fresh one…