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Date: Sun, 17 Dec 2006 23:12:55 -0500
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From: "colyncase on earthlink" <colyncase@earthlink.net>
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Subject: Re: [LML] Re: electric attitude indicators
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I guess I'm not a great fan of using a mems + cpu based unit as a backup.
I like my backup to fail for a different reason than the primary failed.

Aside from that, the unit-volume of all aviation digital ahrs systems 
combined
is so minuscule that if you told me no one had ever been seen to fail in the 
air
I still would not feel warm and fuzzy.

if you are just sold on digital ai's I would find out from Chelton and if 
possible
pinpoint, just how much testing it takes to get these things to work most of 
the
time and then see where these backup units you mention stack up.  I would 
expect
there is a huge gulf between them, and even then, Cheltons have been known 
to
fail.

I went with the full size battery backed life-saver gyro from mid-continent 
as my primary and
a standard vac ai as my backup.

Colyn