Narrative:

Returning to ZZZ about 1hr 20 mins into the flight I had an electronics failure that wound up being an alternator failure. I was on an IFR flight plan; in [TRACON] control; cruising at 7000 ft. I was above an overcast layer that went from 5500-6500. [TRACON] called me up to amend my flight plan; it was at that moment I saw my GPS go blank; I called [TRACON] and indicated I was having an equipment issue and to standby for 1 min. They did not respond. I transitioned from autopilot to hand flying and began to diagnose the GPS failure; at the same time now wondering if the radios also had an issue caused by the unknown elec problem. [TRACON] called again; at this time I tried a backup headset; and used both sets of jacks in the front. Radios were able to receive but not transmit. I then squawked 7600. [TRACON] indicated they could see the squawk; and asked me to ident if I could hear them. I did. At that time I checked my volts and saw I was in a discharge state; down to about 10 volts; and now realized my alternator failed. I now began to consider my options of flying IMC ahead with no electrical power; a moment later I saw a break in the overcast and decided it would be safer to continue below the overcast under VFR; so I squawked 1200 to tell the controller I was going to fly VFR; they did not acknowledge the change; I then descended to 3500 ft and turned off my master to save power for my landing gear. I then began to brief poh to see if I could reset the alternator; and also refreshing the manual landing gear procedure so I would be ready for any option. I was on a straight course to my home airport; but it would take me over the top ZZZ1. I knew the top of class C was 4400; so I climbed to 4500 to go over the top of the class C; and remain about 500-1000 below the ceiling. During the stress of the situation it seemed like the best option. Upon reaching ZZZ I turned on the master and had enough power to lower the gear. I landed fine. I then called tracon to tell them I was on the ground and close my flight plan. I spoke with an instructor today and he mentioned that although I was above the class C; I would need the mode C 'on' to fly over that airspace; so I should have flown around the class C; not over it. I did not catch this.the factors that led to this miss was not having good recall of the far related to the space above controlled airspace with regard to mode C; being more concerned with flying; avoiding IMC with no elec power); wondering if there was a bigger issue brewing (elec fire; or other); fuel burn now that the gas gauges were 'off'; and the stress of not knowing if 10 volts was enough to lower the gear (when it wasn't enough to power my GPS). I have read stories about radio failure in IMC and to fly last cleared flight plan....; however total elec failure is a bigger issue given the loss of turn coordinator. Getting below the IMC layer became my priority. A safety course on how to handle a total elec failure would be good; what to do if you have the option to get safely below the IMC layer; vs if you cant; and what pitfalls to avoid (my over the top of class C example); etc.

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Original NASA ASRS Text

Title: An instrument rated private pilot experienced an electrical system failure in instrument conditions. He was able to locate VFR conditions and continued to his destination.

Narrative: Returning to ZZZ about 1hr 20 mins into the flight I had an electronics failure that wound up being an alternator failure. I was on an IFR Flight Plan; in [TRACON] control; cruising at 7000 ft. I was above an overcast layer that went from 5500-6500. [TRACON] called me up to amend my flight plan; it was at that moment I saw my GPS go Blank; I called [TRACON] and indicated I was having an equipment issue and to standby for 1 min. They did not respond. I transitioned from Autopilot to hand flying and began to diagnose the GPS failure; at the same time now wondering if the Radios also had an issue caused by the unknown Elec problem. [TRACON] called again; at this time I tried a backup headset; and used both sets of jacks in the front. Radios were able to receive but not transmit. I then squawked 7600. [TRACON] indicated they could see the squawk; and asked me to Ident if I could hear them. I did. At that time I checked my volts and saw I was in a discharge state; down to about 10 volts; and now realized my Alternator failed. I now began to consider my options of flying IMC ahead with no electrical power; a moment later I saw a break in the overcast and decided it would be safer to continue below the overcast under VFR; so I squawked 1200 to tell the controller I was going to fly VFR; they did not acknowledge the change; I then descended to 3500 ft and turned off my Master to save power for my landing Gear. I then began to brief POH to see if I could reset the Alternator; and also refreshing the Manual Landing Gear procedure so I would be ready for any option. I was on a straight course to my home airport; but it would take me over the top ZZZ1. I knew the top of Class C was 4400; so I climbed to 4500 to go over the top of the Class C; and remain about 500-1000 below the ceiling. During the stress of the situation it seemed like the best option. Upon reaching ZZZ I turned on the master and had enough power to lower the gear. I landed fine. I then called Tracon to tell them I was on the ground and close my flight plan. I spoke with an instructor today and he mentioned that although I was above the Class C; I would need the Mode C 'ON' to fly over that airspace; so I should have flown around the Class C; not over it. I did not catch this.The factors that led to this miss was not having good recall of the FAR related to the space above Controlled airspace with regard to Mode C; being more concerned with flying; avoiding IMC with no elec power); wondering if there was a bigger issue brewing (elec fire; or other); fuel burn now that the gas gauges were 'off'; and the stress of not knowing if 10 volts was enough to lower the gear (when it wasn't enough to power my GPS). I have read stories about radio failure in IMC and to fly last cleared flight plan....; however total elec failure is a bigger issue given the loss of Turn Coordinator. Getting below the IMC layer became my priority. A safety course on how to handle a total Elec failure would be good; what to do if you have the option to get safely below the IMC layer; vs if you cant; and what pitfalls to avoid (my over the top of Class C example); etc.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.