In a message dated 12/18/2007 3:11:34 P.M. Pacific Standard Time,
VTAILJEFF@aol.com writes:
Do you not consider a
second independent EFIS with it’s own ADAHRS as sufficient backup
Not a simple question--depends on the power distribution design
concept. My first reaction is to suggest you consider the common elements
between the two EFISs--and that would seem to be only the pitot static system
since the Dynon has its own separate battery. When I designed my
electrical system I started with an all electric objective and did all I could
to include simplicity as well as redundancy to keep the motor running. For
a number of reasons that resulted in two Odyssey batteries and one
alternator. Then I added a Chelton Pro--a certified EFIS. So I felt
comfy I had a good AHARS and two high quality displays with redundancy. To
provide a backup for the 2% of the time I am in real IFR I decided a Dynon was
the cost effective answer--I just could not imagine a failure mode that would
leave the motor running and kill both EFISs. But maybe your imagine is
different than mine.