Re: [amsat-bb] Re: The hard questions..

[wa6fwf <wa6fwf@xxxxxxxxxxx>]

On Sunday 15 February 2004 21:22, Stacey E. Mills wrote:

>If we had been clairvoyant we would have probably charged the aux. battery 
>and taken the main battery off line. 

you had earlier mentioned that the command team had noticed battery anomalies 
several months ago...

> Charging the aux. battery would have accomplished nothing unless the
> shorted main battery were also taken off-line. 


If the aux battery would have been completely charged might it not have dumped 
enough energy into the main to possibly burn open the dendrite shorting a 
cell? 

   Or  having the aux battery  fully charged you may have been more prone to 
"cut loose" the main  as you were watching it fail since you would have known 
that you had a good fully charged aux... 

In hindsight at the time of failure,cutting both batteries open might have 
been yet another option, since you could then catch the sat in sunlight and 
look at what was going on with both batts before committing to one or the 
other... but there may be things I'm not aware of that would have  prevented 
this from working...

personally I think the relay design is poor  and connecting a dead aux is not 
much better... diode isolation even though it costs you a voltage drop  would 
have been better, but I know then you couldn't try and save a set of 
batteries until later... every design has tradeoffs.

     I for one no know of no company, group, individual, or doctor...   that 
doesn't do a post-mortem after something goes wrong...   to learn from what 
has happened and to see if anything could have been done differently  in the 
future. But there is no reason for anyone to wrap themselves in self pity or 
to martyr themselves as being to blame, for that is non-productive... but to 
just say it was "inevitable" and lets move along to the next sat without 
reviewing all of the possibilities and options  is equally non-productive.
 

73
Kevin WA6FWF

 There are no secrets to success. It is the result of preparation, hard work, 
and learning from failure.-- Colin Powell



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