[amsat-bb] Re: Was HEO naivete; now GEO rideshare frequency choice, etc.

[Nigel Gunn G8IFF/W8IFF]

Paul Williamson wrote:
>
> "The first burn went relatively well -- there was a small deviation from the expected burn duration, which placed the spacecraft perigee somewhat higher 
than planned. The second burn could not be accomplished because a slow leak in the high-pressure helium system during 
the week the spacecraft was being
reoriented prevented the opening of valves feeding fuel to the thrust assembly."
> The "small deviation" is known to be due to a design error in the simple digital logic circuit that controlled the burn duration.

OK. The helium leak was a propulsion system fault. The design error in the logic was human error and is known so can be 
designed out.


> 
> On AO-13, the kick motor worked exactly as planned, and the spacecraft achieved the intended orbit. But that orbit could have been chosen better, 
as it turned out. The early re-entry after only 8.5 years was not anticipated, and probably could have been avoided if 
we had been smart enough,
soon enough.

Another "human error" Hindsight is wonderful.
I don't think we should reject an option that requires propulsion because of past errors that are now well understood.


-- 
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Nigel A. Gunn. G8IFF   W8IFF (was KC8NHF)
1865 El Camino Drive, Xenia, OH 45385-1115, USA   937 825 5032
e-mail nigel at ngunn.net             www  http://www.ngunn.net
Member of  ARRL, GQRP #11396, QRPARCI #11644, SOC #548,  Flying Pig #385,
                   Dayton ARA #2128,  AMSAT-NA   LM-1691,  AMSAT-UK, MKARS,  ALC
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