I'm still used to the typical world of waxed cardboard constrcution for
model rockets.  I take it you think they wouldn't be able to handle the
stresses of one sort and another.

Do you think we would be able to use a wire-frame type structure with a
paper skin?  That would reduce construction complexity considerably.

Why not run the expansion chamber in a loop, so that the gas is already
expanded before the mixing chamber and thus the area around the nozzels is
self cooling? Oh, wait, liquid propellants... Right.  How about using
butane, instead of kerosene, then?

A carbon fiber frame is likely to be impossible to do for a reasonable
price.  Perhaps we should start by building the nozzels and other propulsion
systems, then move to checking the thrust capability, and compensate for the
construction of the frame acordingly.

Fuels pumps may be a moot point.  As the air pressure decreases with
altitude, captive air in the fuel tanks will begin to force fuel out the
feed tubes.  What then?

--Brendan

> The nozzles and mixing chamber would have to be metal, but the body would
> have to be lighter, as would the tanks..preferably lexan or something like
> a carbon fiber composite, formed around a vac or blow molded liner.
> properly shielded you could have the nozzle in front of the tanks to
reduce
> the shift in moment as the tanks emptied..., a la early Goddard. if
> ceramics were  used for the shield, with a thin beryllium bronze cup as a
> heat dump... you could probably keep things sane until the temperature
> started to drop precipitously at about 40,000 feet, after which heat
> dissipation is not a real problem. I also think that at some point it
would
> be cool to try and launch from a high flying balloon or aircraft, possibly
> even an RC  craft.
>
> Sigh.......
>
> M
>

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