"Dick Morris" wrote in message
...


Vincent Cate wrote:
On the other hand there is not so much room for improvement in rockets.

There's not a lot of room for improvements in efficiency (Isp), but
we've barely scratched the surface as far as cost reduction is
concerned.

Come on now, rockets have been under continous development
for most of a century. There can't be very many ways to improve
engines with that much history. What could you possibly do to
improve them. Are you willing to say that they are not near
perfection now? :-)