Narrative:

Approximately 10 hours prior to this (and 2 weeks earlier) situation, the alternator had gone off line. I thought perhaps I had inadvertently not turned the 'field' switch on, although I purchased new regulator for aircraft, but did not install. While 30 mins into flight alternator went off line, but would recycle for mins at a time. I was on top at 5000 ft. I declared emergency, stated problem and requested descent to VFR. I was cleared to 2000 ft, but continued to 1500 ft MSL (to VFR conditions) using VFR sectional and copilot help. I landed at vct without incident. I replaced volt regulator with spare I was carrying with me, refiled and continued to destination svs without incident. I should have remained at MSA and continued IMC to vct, I had plenty of battery power to conclude flight with power from battery. Although an a&P was available at vct, I chose to replace voltage regulator myself. I should have had the a&P inspect the installation and double check my work prior to re-entering IMC conditions.

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Original NASA ASRS Text

Title: PLT OF AN SMA SEL DECLARED AN EMER AND REQUESTED A LOWER ALT INTO VFR CONDITIONS DUE TO AN ELECTRICAL FAILURE OF THE ALTERNATOR. HE LANDED AT A NEARBY ARPT SAFELY AND CORRECTED THE ELECTRICAL PROB HIMSELF, WITHOUT BENEFIT OF A PROPERLY CERTIFICATED MECH TO INSPECT AND SIGN OFF THE REPAIR AS AIRWORTHY. HE SUBSEQUENTLY TOOK OFF AND CONTINUED TO HIS DEST WITHOUT FURTHER INCIDENT.

Narrative: APPROX 10 HRS PRIOR TO THIS (AND 2 WKS EARLIER) SIT, THE ALTERNATOR HAD GONE OFF LINE. I THOUGHT PERHAPS I HAD INADVERTENTLY NOT TURNED THE 'FIELD' SWITCH ON, ALTHOUGH I PURCHASED NEW REGULATOR FOR ACFT, BUT DID NOT INSTALL. WHILE 30 MINS INTO FLT ALTERNATOR WENT OFF LINE, BUT WOULD RECYCLE FOR MINS AT A TIME. I WAS ON TOP AT 5000 FT. I DECLARED EMER, STATED PROB AND REQUESTED DSCNT TO VFR. I WAS CLRED TO 2000 FT, BUT CONTINUED TO 1500 FT MSL (TO VFR CONDITIONS) USING VFR SECTIONAL AND COPLT HELP. I LANDED AT VCT WITHOUT INCIDENT. I REPLACED VOLT REGULATOR WITH SPARE I WAS CARRYING WITH ME, REFILED AND CONTINUED TO DEST SVS WITHOUT INCIDENT. I SHOULD HAVE REMAINED AT MSA AND CONTINUED IMC TO VCT, I HAD PLENTY OF BATTERY PWR TO CONCLUDE FLT WITH PWR FROM BATTERY. ALTHOUGH AN A&P WAS AVAILABLE AT VCT, I CHOSE TO REPLACE VOLTAGE REGULATOR MYSELF. I SHOULD HAVE HAD THE A&P INSPECT THE INSTALLATION AND DOUBLE CHK MY WORK PRIOR TO RE-ENTERING IMC CONDITIONS.

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.