Michael Belfiore is concerned about Rocketplane’s business plan and technical approach:

These guys say they’ll fly paying passengers–and not just any paying passengers, but ones able to blow almost a quarter of a million dollars on a what amounts to a fabulously expensive roller coaster ride–in an experimental spacecraft built around a used business jet. Because its cheaper.

Well, there’s actually nothing wrong with that. It’s certainly an airframe with which we have a lot of experience (though not necessarily for this application). It’s not at all obvious to me that it’s better to use a new design from scratch. And the fact that it’s used doesn’t bother me, either. Many airliners are flying safely with aging airframes (and we now have B-52s flying some of whose current flight crews may have grandfathers who flew them). What matters is not age (or even cycles), but inspections.

And there’s more, unfortunately. Turns out the rocket engine is going to be preowned as well, of the highly explosive liquid fuel variety. That’s because the built-from-scratch engine they were going to use blew up on the test stand.

Without knowing more about this, I can’t really comment, but liquid engines are not intrinsically dangerous, marketing hype from SpaceDev aside. It depends on the design, and the margins.

And something for me to follow up on: a tipster tells me that Rocketplane hasn’t approached the FAA about certifying their hot-rodded Learjet–surely a requirement for following through with their business plan.

If they haven’t talked to the FAA at all, I’d be concerned (and surprised, if not astonished). But if the “tipster” is saying literally that they haven’t applied for “certification,” I wouldn’t expect them to, now or later. “Certification” has a very precise meaning in this context. The whole purpose of the new launch legislation last year was to allow passengers to fly without having to go through certification of a spaceplane (something that the FAA-AST doesn’t know how to do at all, and that FAA-AVR, the part that certifies aircraft, doesn’t know how to do it for spacecraft).

All that is needed is a launch license. Virgin Galactic may attempt to get their spacecraft certified (because that seems to be Burt’s druthers), but if they do, I suspect they’ll find out that it will throw a wrench into their business plans, cost them a lot more than they expect, and delay their entry into the market for years.

[Update on Sunday night]

Robin Snelson makes a good point in comments–Belfiore is comparing apples and orange. Virgin Galactic is a spaceline, whereas Rocketplane is a manufacturer. Better to compare the latter to the SpaceShip Company.