I’m too busy to blog much, but the Chairforce Engineer has a follow-up to the previous discussion (see here, too) on lunar transportation architectures and L1.

Jon Goff has some useful thoughts on space system design goals, and some advice for Elon Musk:

Take a look at the EELV program, and even SpaceX. EELV’s goal was to reduce the cost of launching satellites for the military from absolutely obscene to merely ridiculous (ie a 50% drop in price IIRC). So, they tried to make some incremental changes to how they build and operate their vehicles. In some areas they’ve gotten a lot better, but the reality is that they didn’t even acheive the modest goals they set out for themselves. It isn’t that they’re dumb, or malicious, or incompetent. It’s just that they set themselves too easy of a goal, so they didn’t actually have to think outside the same high-cost artillery box that they’ve put themselves in over the years.

It should be pointed out that one of the reason that they haven’t achieved the cost reduction goal is the collapse of flight rate. As I pointed out in my New Atlantis piece, flight rate, even for expendables, is a much higher contributor to launch cost than design is.

He also writes something that a younger Jon Goff would have found heresy:

…if they go for the BFR instead of trying to radically change the Earth-to-Orbit transportation market by going fully reusable…They’re probably going to get their lunch eaten. I mean, they could possibly acquire one of the companies that actually develops a fully reusable, high-flight-rate orbital space transport. But the reality is going to be that if they don’t keep pushing more and more reusability into their Falcon line, it’s going to go obsolete.

That’s sort of an inside joke to long-time readers of sci.space.*, but once upon a time, Jon was a, hmmmm…shall we say, vociferous proponent of expendable launchers. It would be interesting (and possibly educational to others) sometime to hear a description of how his thinking has evolved.

Now, we just have to work on his politics…