Originally Posted by BobTurner
I know you asked specifically about the check ride. But the question extends to actual operation in IMC. How many backups, if any, are enough?
That is a question of a different nature: do I have the skill, experience and attitude to avoid entering conditions where I don't have an out in case of hardware failure. The answer, of course, will depend on the individual, their risk-tolerance and phase of the moon. For instance, I fly a BRS parachute, but will take higher risks because of its presence; does that make me a bad person? I don't think your question has an answer other than "Fly Safe, whatever that means to you."
My original question was more along the lines of why are FAA standards so woefully out of date and out of touch with reality. My next airplane will have two independent magnetometers and between three and five independent GPS/WAAS/GLONASS/Galileo/BeiDou receivers active at any time, two of which can drive the autopilot, and all but one survive total electrical system meltdown short of nucular EMP. Plus a handheld or two for COM/NAV backup, should it come to that. It will outperform and out-safetify every club airplane I ever trained in--the weak link is the fuel selector between the ears--but still it won't strictly satisfy the letter of the law for IFR training unless I string a LORAN/ADF lightning rod from the rudder to my posterior...sigh. I'll go pound some rivets now.