Balloons To Give A Spaceship A Head Start?
quibbler
pann...@net.aol.com says...
> A cluster of humongous balloons lifts the spaceship to some
> high altitude, whereupon the spaceship's engines start
> and it goes into orbit, or someplace, more efficiently than
> if it started from the ground.
>
> Any mileage in this idea?
It's called a "rockoon". It's been used since the earliest days of
rocketry. Van Allen used them a bunch.
I'm not sure about the total efficiency gain. One starts the rocket at a
greater height and in less dense air. But the rocket will still have to
achieve escape velocity to reach orbit. So reducing air friction is the
main advantage, it seems. If you do this over the equator and in the
direction of the spin of the earth you can also take advantage of that
source of energy.
Folks like goddard were trying to build solar-thermal planes to fly his
rocket up to high altitude at reasonably high speeds. People are still
kicking around hybrid system designs ideas like this.
--
_____________________________________________________
Quibbler (quibbler247atyahoo.com)
"It is fashionable to wax apocalyptic about the
threat to humanity posed by the AIDS virus, 'mad cow'
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eradicate." -- Richard Dawkins
Fred B. McGalliard
and the like. It used only a single balloon. You might think of what kind of
balloon platform it would take to put up a shuttle sized craft, plus
refrigerators for the LH2, pressurized crew compartments so they don't have
to spend hours in the vehicle itself. It gets pretty big, and expensive, and
a bit hard to do last minute repair and launch activities. I still think
it's a good idea. A semi permanent platform, shaped into a donut by
pressure, with the vehicle in the center, and a service platform with a
runway on top, drops down to pick up crew and payload and such, floats up to
mate with the launch vehicle.
"Leon Pann" <pann...@net.aol.com> wrote in message
news:d45439e0f6172673...@remailer.frell.eu.org...