A question from Yahoo! Answers:

Why was the flying shuttle important? What evironmental impact did it have?

If you’re talking about the space shuttle, it’s not important and never was. For starters, it’s a manned vehicle, which means it’s inferior to unmanned ones; there is nothing in space that a man can do better than a machine. When used as a launch vehicle, the space shuttle system is hugely inefficient; a decent traditional carrier rocket can carry a payload worth over 3% of its lift-off weight; space shuttle, only about 1% (for example, a Delta IV rocket can carry up to 25 metric tons to a low orbit vs. 23 tons by the space shuttle, but Delta IV’s lift-off weight is 733 tons, while the space shuttle’s is 2,029 tons). The safety record is spotty, too…

In defense of the space shuttle designers, it must be said that all these issues are obvious in retrospect, but were not so obvious back when the development of the space shuttle was commissioned. Back then, the space shuttle was envisioned as a cost-effective easy-to-maintain alternative to traditional carrier rockets. Needless to say, though, those visions proved to be unrealistic…