Re: [amsat-bb] KITSAT-3 launch

[Stephan Greene <sgreene@xxxxxxxxxxx>]

On Tue, 25 May 1999, Jeff Davis wrote:

> Quoting Dave Cawley (Timestep@dial.pipex.com) [990525 12:28]:
> > 
> > And is yet another example of a university being able to launch a satellite,
> > but no replacement for OSCAR 13 yet ?
> > Seems increasingly daft to me ?
> 
> Why does it seem so daft that a university can hitchhike a low-earth orbit for
> a 10 pound bird that is carrying no explosive fuel?
> 
> P3D is a "big boy" requiring a "big ride". :)

In addition,LEO is an easier environment and it's easier to get a ride:

- less stressful radiation environment
- magnetic and gravity gradient (passive) stabilization feasible
- easier link budget
- no propulsion requirement and a spring is your deployment mechanism
- lower delta-v means more ride opportunities
- small means more ride opportunities

The jump from building even a complex computer-controlled spacecraft for
LEO to a Molniya-orbit P3x design is non-trivial:

- Active attitude control
- on-board propulsion to get to final orbit
- greater distance means more u/l and d/l power
- much tougher radiation environment
- more complex ground control requirements
- more complex launch integration

Finally, I wonder if universities see a bent-pipe transponder as less of
an intellectual challenge vs. the LEO designs.

OTOH, I am VERY thankful they are building and flying these birds at all.

73 Steve  KA1LM


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Stephan A. Greene      Beeper: 1-800-759-8888 PIN 1030552# 
sgreene@washsq.com     IT Product Devel, Washingotn Square Associates Inc
sgreene@patriot.net    Personal
ka1lm@amsat.org        Amatuer  KA1LM  Grid FM18hx                      
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