I've heard:

"designed upside down"
"incorrect engineering drawings"

>From the picture, it appears to be a Select Controls G-switch, (or one virtually identical to it), which is the very same used in most of the hobby rocketry electronics.  Its a switch originally used by the military for launch detect, in things like the Hellfire missile.  I know the documents at Select Controls must be correct (unless they've changed) because I've used it on a pc board, for timer initiation after launch detect, in a hobby rocketry electronics device.

I'll bet anything the error came in the CAD Schematic/PCB library component construction for that part.  Part was probably installed on the board exactly in the orientation shown on the silkscreen & passed all the visual 'inspections'.  2 switches in each of two systems, all laid out from the same pcb library & all wrong. 

Gary Crowell 




> -----Original Message-----
> From: piclist-bounces@mit.edu 
> [mailto:piclist-bounces@mit.edu]On Behalf
> Of M. Adam Davis
> Sent: Monday, October 18, 2004 10:36 AM
> To: Microcontroller discussion list - Public.
> Subject: Re: [OT] Genesis crash linked to upside-down (sensor) design
> 
> 
> Should have used a multiple axis switch (or accelerometer) with a 
> computer function that told whether the switch was in a 
> correct state at 
> any given time.
> 
> Should have also considered radio control - if chute doesn't pop in 
> time, pop it by command.  They were sufficiently close enough 
> to send a 
> strong enough signal to command the thing.
> 
> Oh well.  I bet the design engineers and those who signed off on the 
> document are getting their beatings.
> 
> -Adam
> 
> Peter Johansson wrote:
> 
> >>From the d'oh! department...
> >
> >
> >Genesis crash linked to upside-down design
> > 
> >17:18 15 October 04
> > 
> >NewScientist.com news service
> > 
> >
> >Sensors to detect deceleration on NASA's Genesis space capsule were
> >installed correctly but had been designed upside down, resulting in
> >the failure to deploy the capsules parachutes. The design flaw is the
> >prime suspect for why the capsule, carrying precious solar wind ions,
> >crashed in Utah on 8 September, according to a NASA investigation
> >board.
> >
> >
> >Remainder of the article available at:
> >
> >http://www.newscientist.com/news/news.jsp?id=ns99996541
> >
> >-p.
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> >
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