Narrative:

Shortly after departing mto on an IFR clearance, I experienced electrical problems. I noticed a bad alternator, so I shut everything I could down and tried to self excite the alternator. About 1 min after that I lost the other alternator. I told cmi approach I was having trouble, but before I could request vectors to cmi I lost total electrical. I had a hand-held transceiver to listen, but I could not transmit. I also had a hand-held GPS and used that to navigation to C77 my destination. I also knew it was VFR at C77 so I continued my flight north, as I was cleared. I left the electrical off, once in a while I would turn on the radios after letting the battery charge, I could transmit for about 7-10 seconds. So I let ZAU know what was going on, they were helpful and had me as a primary target. I heard them on the hand-held let me descend to 3000 ft, so I did, but it did not get me out of the clouds. Then I let the battery charge enough to contact rfd as I got about 45 mi south of rfd, they then let me down further, still in IMC. As I got about 20 mi south of C77 I broke out into VFR WX. I continued and landed at C77 and called rfd tower and told them I was on the ground and safe. I thanked them and they said they followed me on radar and everything was ok. Turns out after inspecting the aircraft mechanics said on 1 alternator the belt broke and the other terminal burned out. Two totally unrelated problems.

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Original NASA ASRS Text

Title: PLT OF A C310 LOST COM DUE TO BOTH ALTERNATORS FAILING FOR DIFFERENT REASONS. PLT USED A HAND-HELD RECEIVER TO RECEIVE BY AND HAND-HELD GPS NAV RECEIVER TO CONTINUE TO DEST WHERE A SUCCESSFUL LNDG WAS MADE IN VFR CONDITIONS. ATC KEPT HIM IN RADAR CONTACT AND HEARD HIM ON SOME OCCASIONS WHEN XMITTED WITH SOME BATTERY PWR.

Narrative: SHORTLY AFTER DEPARTING MTO ON AN IFR CLRNC, I EXPERIENCED ELECTRICAL PROBS. I NOTICED A BAD ALTERNATOR, SO I SHUT EVERYTHING I COULD DOWN AND TRIED TO SELF EXCITE THE ALTERNATOR. ABOUT 1 MIN AFTER THAT I LOST THE OTHER ALTERNATOR. I TOLD CMI APCH I WAS HAVING TROUBLE, BUT BEFORE I COULD REQUEST VECTORS TO CMI I LOST TOTAL ELECTRICAL. I HAD A HAND-HELD TRANSCEIVER TO LISTEN, BUT I COULD NOT XMIT. I ALSO HAD A HAND-HELD GPS AND USED THAT TO NAV TO C77 MY DEST. I ALSO KNEW IT WAS VFR AT C77 SO I CONTINUED MY FLT N, AS I WAS CLRED. I LEFT THE ELECTRICAL OFF, ONCE IN A WHILE I WOULD TURN ON THE RADIOS AFTER LETTING THE BATTERY CHARGE, I COULD XMIT FOR ABOUT 7-10 SECONDS. SO I LET ZAU KNOW WHAT WAS GOING ON, THEY WERE HELPFUL AND HAD ME AS A PRIMARY TARGET. I HEARD THEM ON THE HAND-HELD LET ME DSND TO 3000 FT, SO I DID, BUT IT DID NOT GET ME OUT OF THE CLOUDS. THEN I LET THE BATTERY CHARGE ENOUGH TO CONTACT RFD AS I GOT ABOUT 45 MI S OF RFD, THEY THEN LET ME DOWN FURTHER, STILL IN IMC. AS I GOT ABOUT 20 MI S OF C77 I BROKE OUT INTO VFR WX. I CONTINUED AND LANDED AT C77 AND CALLED RFD TWR AND TOLD THEM I WAS ON THE GND AND SAFE. I THANKED THEM AND THEY SAID THEY FOLLOWED ME ON RADAR AND EVERYTHING WAS OK. TURNS OUT AFTER INSPECTING THE ACFT MECHS SAID ON 1 ALTERNATOR THE BELT BROKE AND THE OTHER TERMINAL BURNED OUT. TWO TOTALLY UNRELATED PROBS.

Data retrieved from NASA's ASRS site as of July 2007 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.