[amsat-bb] Re: spaceflight(launch) question

[G0MRF@aol.com]

Hi.
 
Nice thought.
 
As far as I am aware, Ion thrusters need a lot of DC power, although low  
power (80W or so) have been developed.
But there are still two problems. One is the restrictions on propellent on  
the ISS / shuttle. Even though Xenon gas is 'harmless' it still posses a hazard 
 due to fuel tank pressure and a contamination risk if it leaks into the  
habitable areas.
The other problem is the thrust developed by a small Ion drive is really  
very small. Probably less than 10 milli Newtons.  Given the drag on the  solar 
panels at 350km, it may be that the thrust is too little to overcome the  drag.
 
Pulsed plasma technology may be better as it only needs Teflon and DC  power, 
so no risk to crew.
 
But propulsion on a LEO as a concept has to be a winner.
 
Thanks
 
David  G0MRF
 
 
 
In a message dated 01/11/2008 03:12:10 GMT Standard Time,  
sparkycivic at shaw.ca writes:

I was  wondering... An question just occured to me that I couldn't answer: If 
a small  satellite were hand-launched from the space station, and it 
contained an  ion-drive motor powered by electricity, would it ever be able to 
accelerate in  order to gain a higher orbit, or would that require an impracically 
large  power supply/engine?  In other words, could that method be used to  
achieve higher orbits with communication/ham class satellites without having  to 
use the typical large rocket we've been using all this time?  Also,  would there 
be a cost-advantage to this  method?