For all these who want to fly a PAR or SRA in a G1000 Cirrus with blank screens, please remember that the standby AI is powered from two buses: ESS1 and MAIN1. Which also power the PFD and MFD, respectively, so both have probably failed. The standby AI has no internal backup battery!
In fact, the displays are powered from FOUR different buses and both alternators at all times - PFD from ESS1 (both alternators, also BAT2) and MAIN2 (ALT2); MFD from MAIN1 (confusingly ALT2) and MAIN3 (ALT1 and BAT1).
If the standby AI shows the warning flag, which very likely it will, and you are in IMC, it is parachute time.
If you have time to troubleshoot a bit in VMC, you could take out the cat's cradle Cirrus call the electrical system diagram and understand the electrical system, and then isolate the ESS1 bus from the rest of the system by pulling the ESSENTIAL POWER circuit breaker. If that restores power to the AI, great; now you run 1 NAV, 1 COM, PFD, 1 AHRS and the ADC from BAT2 only.
That will last for about 30 minutes (good luck finding that information in flight). So no hour long cruise to the the next PAR controller, thanks.
In an all electrical aircaft, you are relying on the redundancy of the electrical system. While not the best designed, the Cirrus system is quite redundant, so complete failures are extremely unlikely.
Last edited by Cobalt; 16th Jul 2012 at 18:58.