Narrative:

Flew to ZZZ with the owner of the plane. Dropped him off there and was headed back to home airport ZZZ1. Just about half way through the flight when I had just switched from the auxiliary fuel tanks I became concerned that the switching of the auxiliary fuel pumps had somehow put too much load on the alternator because just as I turned the fuel pumps on then back off is when my GPS began to flicker and the screen began to move back and forth in a distorted way. I decided to reach out to ATC because after seeing some flickering of the GPS I thought it may have been affecting radios and transponder as well. I decided to turn off the navigation lights and found that the GPS stabilized. I notified ATC center I was having some issues with GPS and thought it may be electrically related and wanted to make sure they could still hear me and I was still under radar contact. They told me that they didn't see me on the radar and to cycle my transponder so I did and they were able to identify me. I noticed the ammeter was still positive so I told them I believed to have it stabilized and would advise if I had any further issues. A few moments later (maybe 2 minutes) I noticed the ammeter began flickering back and forth then pegged itself at zero. I proceeded through the alternator failure checklist and through this process I realized I was running on battery. During the checklist of switching things off and on to identify the issue the GPS cycled off and back on. I realized both alternators had failed and so I wasn't really sure how long I had been definitely running on battery so I slowed the plane to vlo and attempted to extend the gear. The entire electronics including radios transponder and GPS were now flickering off and on and the turn coordinator showed a red flag. I believed that I would lose communication momentarily so I noted the frequency and punched in 7600 identify on my transponder to alert ATC I was losing communication. Just after I hit identify the entire electrical system shut off. I lost RPM gage; turn coordinator; engine monitors; fuel gages; flaps; landing gear; gps; radios and transponder. I followed safety procedure for total electrical failure and turned off all electrics and avionics and master switch. I contacted ATC by my handheld radio and requested a vector to the nearest suitable airport to land. I informed ATC I had a total electrical failure and did not know if my gear was up or down. I had felt the gear begin to come down but there were no lights so I wasn't sure. ATC vectored me over ZZZ2 for two low approaches. The first low approach I flew to just 1;100 feet just below traffic pattern altitude because I was concerned about over-stressing the engine since I had no way to see what my RPM was reading. ATC informed me that my gear was not down. I requested a hold vector for time to get my gear down with emergency extension tool. I followed the emergency checklist to extend the gear and while on a 090 heading at 2;000 feet I was able to put the gear down using the emergency lever. I then was given another vector to perform a low approach. This time I was informed the gear 'appeared to be down'. After this ATC had me turn left for a right downwind for runway 36. I was able to land on 36 and the gear was in fact down and I had no issues landing without flaps there was plenty of runway. I was followed by large trucks and I believe the airport manager along with some fireman and airport employees greeted me on the ground to make sure I was alright and take my name and number. I feel that I followed all safety protocol and made the best decision. If I had to do this again I would have lowered my gear at the first indication of electrical issues and landed at the first suitable airport which would have likely still been ZZZ2 but at least I may have gotten the gear down before the electrical system failed. I was glad I was able to alert ATC of an issue just in time and I was extremely glad I had the handheld radio with me.

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Original NASA ASRS Text

Title: PA30 pilot reported the failure of the electrical system resulted in a diversion and manual gear extension.

Narrative: Flew to ZZZ with the owner of the plane. Dropped him off there and was headed back to Home airport ZZZ1. Just about half way through the flight when I had just switched from the auxiliary fuel tanks I became concerned that the switching of the auxiliary fuel pumps had somehow put too much load on the alternator because just as I turned the fuel pumps on then back off is when my GPS began to flicker and the screen began to move back and forth in a distorted way. I decided to reach out to ATC because after seeing some flickering of the GPS I thought it may have been affecting radios and transponder as well. I decided to turn off the navigation lights and found that the GPS stabilized. I notified ATC center I was having some issues with GPS and thought it may be electrically related and wanted to make sure they could still hear me and I was still under radar contact. They told me that they didn't see me on the radar and to cycle my transponder so I did and they were able to identify me. I noticed the ammeter was still positive so I told them I believed to have it stabilized and would advise if I had any further issues. A few moments later (maybe 2 minutes) I noticed the ammeter began flickering back and forth then pegged itself at zero. I proceeded through the alternator failure checklist and through this process I realized I was running on battery. During the checklist of switching things off and on to identify the issue the GPS cycled off and back on. I realized both alternators had failed and so I wasn't really sure how long I had been definitely running on battery so I slowed the plane to VLO and attempted to extend the gear. The entire electronics including radios transponder and GPS were now flickering off and on and the turn coordinator showed a red flag. I believed that I would lose communication momentarily so I noted the frequency and punched in 7600 IDENT on my transponder to alert ATC I was losing communication. Just after I hit IDENT the entire electrical system shut off. I lost RPM gage; turn coordinator; engine monitors; fuel gages; flaps; landing gear; gps; radios and transponder. I followed safety procedure for total electrical failure and turned off all electrics and avionics and master switch. I contacted ATC by my handheld radio and requested a vector to the nearest suitable airport to land. I informed ATC I had a total electrical failure and did not know if my gear was up or down. I had felt the gear begin to come down but there were no lights so I wasn't sure. ATC vectored me over ZZZ2 for two low approaches. The first low approach I flew to just 1;100 feet just below traffic pattern altitude because I was concerned about over-stressing the engine since I had no way to see what my RPM was reading. ATC informed me that my gear was not down. I requested a hold vector for time to get my gear down with emergency extension tool. I followed the emergency checklist to extend the gear and while on a 090 heading at 2;000 feet I was able to put the gear down using the emergency lever. I then was given another vector to perform a low approach. This time I was informed the gear 'appeared to be down'. After this ATC had me turn left for a right downwind for runway 36. I was able to land on 36 and the gear was in fact down and I had no issues landing without flaps there was plenty of runway. I was followed by large trucks and I believe the airport manager along with some fireman and airport employees greeted me on the ground to make sure I was alright and take my name and number. I feel that I followed all safety protocol and made the best decision. If I had to do this again I would have lowered my gear at the first indication of electrical issues and landed at the first suitable airport which would have likely still been ZZZ2 but at least I may have gotten the gear down before the electrical system failed. I was glad I was able to alert ATC of an issue just in time and I was extremely glad I had the handheld radio with me.

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.