Voldenuit wrote:I'm not sure the concept was all that good to begin with. Making a spacecraft reusable ups complexity, ups weight (which reduces payload and range), ups cost, and reduces reliability and safety.
There are good reasons no other space program uses a reusable vehicle (and no, the Buran doesn't count, as it only flew once, and that without any crew on board, before getting canned). SpaceShipOne and Two don't count either, as they are both suborbital craft, and don't face high reentry stresses due to the low speed of reentry.
What about SpaceX's Falcons? It's not a current capability, but Musk's stated that all stages of the Falcon 9 are ultimately intended to be reusable (SpaceX's inability to recover the first stage was their only disappointment on the first test flight), and the the Dragon capsule could actually be reused without so much as replacing the heatshield.
That's a good point. I suppose I wasn't entirely clear about what I meant when I said 'reusable vehicle'. Designing a spacecraft that is meant to survive reentry indefinitely (as the shuttle was), and carting the main engine with you all the way up and down again is an example of 'full reusability' that complicates design and adds weight to spacecraft.
At the other end of the spectrum, we have 'recoverability' - for example, the shuttle booster casings are recovered after launch, and if they are in good enough shape after landing, are refurbished. Falcon 9's *proposed* reusability falls in this category, although they are more complex than the solid rockets used for the shuttle boosters, being a liquid fueled design*. Designing for recoverability adds less weight and complexity than full reusability, and unlike the former, is less likely to drive the design stage in unforeseen directions.
The reentry capsule for Dragon is an example of 'limited reusability'. The capsule is rated for (I believe) a certain number of reentries before it is scrapped and replaced by a new one. This was the same idea behind the Orion CEV that was being developed at NASA before it was shelved.
I think that SpaceX's goals with the Falcon and Dragon are sensible, and one way to reuse spacecraft components sensibly and economically. That is, of course, if it works.
* This makes them more easily damaged on reentry, and is probably why SpaceX is planning on sea recovery for the first (and second?) stage(s).
Wind, Sand and Stars.