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RE: starship-design: How to build a station.

> -----Original Message-----
> From: L. Parker [mailto:lparker@cacaphony.net]
> Sent: 20 April 2000 23:25
> To: 'pk'; 'N. Lindberg'
> Cc: 'starship design'
> Subject: RE: starship-design: How to build a station.
> Ahh, he does mean monopropellant, of which Hydrazine is NOT an example.
> monopropellants are solids and almost have to be by definition, and
> are not suitable for scramjets, ramjets, etc. If, on the other hand, you
> referring to hypergolic propellants (say explosives), I would advise
against them.
> They are volatile and tricky to handle. The Federal government doesn't
even allow
> transport of the components within fifty miles of each other.
> Lee

Quick correction - hydrazine *is* indeed a monopropellant. Example: on two
of the satellites we operate, it is stored in liquid form under pressure, in
titanium alloy tanks. Opening a tank valve results in the hydrazine liquid
being pressure-fed to a thruster, where it passes over a catalyst bed and
decomposes to provide thrust.

Another method that can be employed is to use a small amount of oxidiser to
provide a hypergolic reaction - the thermal energy causing decomposition.
Once the oxidiser is used up, the reaction continues as the hydrazine
rapidly decomposes. 

The catalytic reaction mentioned above is exothermic, which provides enough
heat to start and maintain the decomposition process.