Stefan writes:

Ok, so you want the FAA jump in and require full redundancy on all
instruments for all privately operated light singles to be considered
airworthy? I'm not sure you really want this.

It wouldn't be a bad idea for computer equipment, but it's not enough.
It would be necessary to require not only redundant systems, but
systems with independently-developed software, so that failure modes
of one system don't match failure modes of the back-ups.

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