Narrative:

After departing the airport; I noticed an intermittent low voltage warning from the annunciator; something I had seen in climb out 2 days earlier. In this case; I was able to see the ammeter confirm a discharge. My assumption was that the alternator coupler drive was beginning to slip. This has occurred in the past and indications were similar. This distraction my attention and I turned to the first fix in my IFR clearance although I had been given a heading to follow. The controller corrected me. After landing at my fuel stop; I was able to easily start the engine; which made me believe that I had only slightly discharged the battery. Because it was typical for the low voltage light to flash at low RPM's and the flashing was intermittent at run-up; I departed the airport. Shortly; after raising the gear and flaps; my radios and transponder failed. Using a backup handheld radio; I was able to contact ATC and advise of my situation; although communication was intermittent and I was preoccupied with determining the best course of action. I ultimately decided to continue VFR to my home base. En route; I decided to lower the landing gear fearing that I might not have enough battery power left when I arrived at my destination 2 hours away. What I had not factored in was the reduced airspeed brought about by the gear being down. This increased my en route time to 2 hours 30 mins and caused me to arrive at my destination at dusk. Although I was able to activate runway lights; announce my intentions and land safety; I did so without any exterior lighting. Reflecting on this; I should have taken the intermittent annunciator light more seriously. I should have refueled at the intermediate airport and departed immediately or sought maintenance at that field.

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Original NASA ASRS Text

Title: DISTRACTED BY AN ELECTRICAL PROB; MOONEY M20K PLT HAS A TRACK HDG DEV WHILE DEPARTING MCI.

Narrative: AFTER DEPARTING THE ARPT; I NOTICED AN INTERMITTENT LOW VOLTAGE WARNING FROM THE ANNUNCIATOR; SOMETHING I HAD SEEN IN CLBOUT 2 DAYS EARLIER. IN THIS CASE; I WAS ABLE TO SEE THE AMMETER CONFIRM A DISCHARGE. MY ASSUMPTION WAS THAT THE ALTERNATOR COUPLER DRIVE WAS BEGINNING TO SLIP. THIS HAS OCCURRED IN THE PAST AND INDICATIONS WERE SIMILAR. THIS DISTR MY ATTN AND I TURNED TO THE FIRST FIX IN MY IFR CLRNC ALTHOUGH I HAD BEEN GIVEN A HDG TO FOLLOW. THE CTLR CORRECTED ME. AFTER LNDG AT MY FUEL STOP; I WAS ABLE TO EASILY START THE ENG; WHICH MADE ME BELIEVE THAT I HAD ONLY SLIGHTLY DISCHARGED THE BATTERY. BECAUSE IT WAS TYPICAL FOR THE LOW VOLTAGE LIGHT TO FLASH AT LOW RPM'S AND THE FLASHING WAS INTERMITTENT AT RUN-UP; I DEPARTED THE ARPT. SHORTLY; AFTER RAISING THE GEAR AND FLAPS; MY RADIOS AND XPONDER FAILED. USING A BACKUP HANDHELD RADIO; I WAS ABLE TO CONTACT ATC AND ADVISE OF MY SITUATION; ALTHOUGH COM WAS INTERMITTENT AND I WAS PREOCCUPIED WITH DETERMINING THE BEST COURSE OF ACTION. I ULTIMATELY DECIDED TO CONTINUE VFR TO MY HOME BASE. ENRTE; I DECIDED TO LOWER THE LNDG GEAR FEARING THAT I MIGHT NOT HAVE ENOUGH BATTERY PWR LEFT WHEN I ARRIVED AT MY DEST 2 HRS AWAY. WHAT I HAD NOT FACTORED IN WAS THE REDUCED AIRSPD BROUGHT ABOUT BY THE GEAR BEING DOWN. THIS INCREASED MY ENRTE TIME TO 2 HRS 30 MINS AND CAUSED ME TO ARRIVE AT MY DEST AT DUSK. ALTHOUGH I WAS ABLE TO ACTIVATE RWY LIGHTS; ANNOUNCE MY INTENTIONS AND LAND SAFETY; I DID SO WITHOUT ANY EXTERIOR LIGHTING. REFLECTING ON THIS; I SHOULD HAVE TAKEN THE INTERMITTENT ANNUNCIATOR LIGHT MORE SERIOUSLY. I SHOULD HAVE REFUELED AT THE INTERMEDIATE ARPT AND DEPARTED IMMEDIATELY OR SOUGHT MAINT AT THAT FIELD.

Data retrieved from NASA's ASRS site as of January 2009 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.