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Article #134Re: nasa-celebrates-successful-mars-landing
From: Walter Banks
Date: Tue, 07 Aug 2012 16:20
Date: Tue, 07 Aug 2012 16:20
32 lines
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2541 bytes
Grant Edwards wrote: > On 2012-08-06, Don McKenzie <5V@2.5A> wrote: > > > Been there, done that :-) > > > > http://www.abc.net.au/news/2012-08-06/nasa-celebrates-successful-mars-landing/4180454 > > I thought the over-hyped commentary during the landing and especially > in pre-landing videos (like the "Seven Minutes of Terror") was > embarassing and made the design engineers and mission planners sound > incompetent. > > The commentators kept yammering on about how there was "zero margin > for error", and how "absolutely everything has to work right". > > Really? A design with _zero_ safety margin? Who signs off on a > system design or mission plan like that? > > I'm pretty sure that the "absolutely everything has to work right" is > also bullshit. I heard several people who seemd know know which way > was up talking about redundancy in the hardware design, the software > design, and in the mission planning itself. There was certainly lots of redundancy. One number that is still impressive was that with all of the redundancy NASA identified about 250 remaining single point possible failures. The math on that many series terms makes the comment understandable. w..
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From: Walter Banks <walter@bytecraft.com>
Newsgroups: sci.electronics.design,aus.electronics,comp.arch.embedded
Subject: Re: nasa-celebrates-successful-mars-landing
Date: Tue, 07 Aug 2012 12:20:36 -0400
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