Previously on rec.arts.sf.tv.babylon5.moderated, Chris Adams said:
> Once upon a time, Jeffrey Kaplan said:
> >I'm not an engineer, I never claimed to be. I can't build the thing.
>
> You said "any of us here".
I also said "basic design criteria", not "blueprints".
> >> The amount of energy required to get to low Earth orbit is massive when
> >> compared with air flight. The top speed of a 747 is 567 mph; Shuttle
> >> orbital velocity is about 17,500 mph.
> >
> >Use jet engines for horizontal lift-off and flight up to the upper
> >atmosphere, and then light off the rockets for the push into orbit.
>
> Did you read what I wrote? The altitude isn't the problem; it is the
> velocity. The jets can get you up to maybe 3% of the necessary
> velocity. You haven't gained much, but now you are lugging a bunch of
Which jets are you referring to? And also note that I did not suggest
using jets all the way. I specifically suggested multiple engine types
for different stages of the ascent.
> dead weight in engines and fuel tanks.
Overall, is it more dead weight that having to lift the oxidizer for
your rockets for the atmospheric flight section? Someone stated that
it's the oxidizer that takes up so much of the tonnage of the fuel.
An additional potential benefit of having a jet powered ascent stage is
that if you can get a slow enough re-entry, you can then have a powered
landing approach. This, if possible, would allow for a wider range of
landing sites in the event of an emergency. And then being able to
move the ship to its launch field on its own power later, rather than
having to mount it on a transport vehicle.
--
Jeffrey Kaplan www.gordol.org
Double ROT13 encoded for your protection
Peter's Top 100 Things I'd Do If I Ever Became An Evil Overlord, #46.
If an advisor says to me "My liege, he is but one man. What can one
man possibly do?", I will reply "This." and kill the advisor.
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