Narrative:

I was on an IFR flight in visual conditions from ZZZ to ZZZ1. It was my fourth flight in this aircraft. The first 2 were chkout flts and the third was a VFR solo flight. As we approached the area; I noticed that the stormscope display failed. I was not intimately familiar with this aircraft but the stormscope output to the GPS still appeared to be functioning. I noticed that the ammeter reading appeared to be low; though it was above zero and the alternator annunciator was not illuminated. I tested the alternator annunciator bulb (as I had done before flight) to make sure. As we were in the class B airspace; the ehsi indicated that the inverter frequency was too low. I then noticed that; although there was no autoplt installed and it was placarded inoperative; the autoplt annunciators (presumably driven by the GPS unit which was installed) were all flashing. I assumed that there was something wrong with the ehsi and that its output to the GPS unit was faulty. I did not draw a connection with the previous stormscope failure nor did I decide to turn back to VFR conditions. As I was being vectored; the ehsi went blank and then rebooted. It came back for several seconds and then rebooted again. I missed a few ATC calls at this time and was warned that I was headed for a restr area. I corrected by turning with reference to the magnetic compass. I was in VMC at the time. I determined at this time that the ammeter reading was very low and almost on zero. I informed ATC that my directional gyro had failed and I requested no-gyro vectors. While I was in VMC and could turn without too much danger; specific headings with a magnetic compass are too challenging while trying to deal with such a situation. I was vectored to the localizer course for the ILS at ZZZ1. I was instructed to descend to 3500 ft MSL but requested to remain at 4000 ft MSL. The tops were slightly below that level; though I did not tell ATC why I requested 4000 ft. When I was close to the localizer course; I was cleared for the approach though I did not receive a no-gyro vector onto the final approach course. This was really the most critical turn and I was surprised that I had to make it myself. I flew slightly through the final approach course before realizing that I was not going to get the start turn/stop turn instructions. The first approach was botched right as I reached the tops and ATC canceled my clearance and had me climb and vectored me back around. At this point I remembered the partial-panel screen on the garmin 296 that was mounted on the yoke. This proved to be an amazing asset on the second approach. I was vectored back around onto the approach and told ATC why I wanted to stay at 4000 ft. I asked to turn off my transponder to save battery power but she informed me that I couldn't be vectored in that case. She vectored me onto the localizer further out and I turned on course. At this time my garmin 430; which I was using to communication with ATC; rebooted. I was already using my second navigation radio for the localizer and GS since the ehsi (which is connected to the 430) was dead. I decided to turn off the 430 and use communication 2 and navigation 2. I asked ATC for her frequency. There was some confusion about whether I was asking for the localizer frequency; but she eventually told me the frequency we were using to communication (which I could not read off communication 1 because it was in the process of rebooting; though it seemed to send and receive fine). Once established and descending into the cloud tops at 3700 ft MSL; I used the garmin 296 as a pseudo HSI. I didn't fly the best approach ever; but the needles never were more than about 1/2 scale deflection. Once I got my scan of the normal instruments to include the handheld GPS; I got the needles centered and was doing ok before breaking out at 2000 ft MSL. The tower asked if I had the field in sight. I replied that I did and was cleared to land. Shortly thereafter; the speaker made a bad buzzing sound. Concerned that the avionics may be damaged by low voltage; I turned off the avionics master and everything except the fuel pump. I followed the visual GS indicator and landed uneventfully. I taxied off the runway and looked at the tower and saw a solid green light. I looked down to retract the manual flaps and turn off the fuel pump and the master switch. I looked up and saw a flashing green light and then realized that the earlier solid green was an error on the tower's part; though I certainly was not going to follow their instructions and take off again. I taxied and parked uneventfully. After exiting the airplane; I noticed that the alternator belt was quite loose and could be turned by hand. The mechanic at the flying club I rented from had just returned the airplane to service and he mentioned before I left that he had changed the oil and the alternator belt. I forgot his comment until after landing. I should have remembered it when the stormscope failed. I should have asked the approach controller for the nearest VFR WX (or; more precisely; the nearest airport with no ceiling since ZZZ1 was technically VFR with an approximately 2000 ft ceiling). If I lost all power above the clouds then my localizer and GS needles would have been useless. I could have done a NORDO localizer approach using the handheld GPS (which is not legal but probably reasonable under 91.3 in such an emergency) or gone to another airport (probably a better idea). Figuring out that alternate would have been prudent (and I had not filed an alternate because the marine layer was supposed to have broken up by this time). I also should have announced my intentions in case of a missed approach (if below the clouds; maintain VFR and enter the ri pattern to try again). I think that they could have figured that out but it doesn't hurt to be explicit. I was relatively unfamiliar with the ammeter installed in this piper. The cessna ammeters that I usually see have a clear charge/discharge indication. This piper ammeter basically requires the pilot to know the normal indication and judge whether the needle is above or below that point. I prefer the cessna charge/discharge meter which should normally point at or near zero since that doesn't require knowledge of the power drawn by various loads. The ATC people were excellent and the handheld GPS was a valuable asset with its depiction of the HSI and turn coordinator (though I am happy that the aircraft's turn coordinator never died). I am glad that the aircraft had an ehsi instead of a normal HSI or directional gyro. The failure of the ehsi meant that the screen was entirely blank. While I did carry some instrument covers and could have retrieved them; it was 1 less thing to worry about. Having the instrument be completely dark avoided any confusion where I was looking at incorrect information. Should I have done the approach into ZZZ1; I think that it was not very hazardous because my attitude indicator worked properly; I was in VMC until established (so I only needed to fly a straight line descent); it was an ILS (which is easier than an NDB or some other non-precision approachs); the ceiling was about 2000 ft AGL; and I had limited battery life remaining. If the electrical system had totally failed; I did have enough fuel to get to a VFR airport with reserves. I did not want to transit the class B with no electrical system (no transponder and no ATC communication). Should I have declared an emergency explicitly? ATC was well aware of my situation and I had described the nature of my problem and the potential impacts. The tower was informed that my radio might die on the approach. I think that declaring an emergency would have been appropriate though it was not required and so I did not do so. I also did not want to panic my passenger with that word and descriptions of them as 'souls' (which I find to be a grim term). Should I have noticed the failure earlier? Definitely. I was expecting an alternator failure to be accompanied by an annunciation and perhaps some large event. I'm much more aware of this gradual chain of events than before. I'm glad that it all turned out fine and I can learn from the experience.

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Original NASA ASRS Text

Title: PA32 PLT RPTS ALTERNATOR FAILURE ON IFR FLT AND STEPS TAKEN TO LAND AT INTENDED DEST.

Narrative: I WAS ON AN IFR FLT IN VISUAL CONDITIONS FROM ZZZ TO ZZZ1. IT WAS MY FOURTH FLT IN THIS ACFT. THE FIRST 2 WERE CHKOUT FLTS AND THE THIRD WAS A VFR SOLO FLT. AS WE APCHED THE AREA; I NOTICED THAT THE STORMSCOPE DISPLAY FAILED. I WAS NOT INTIMATELY FAMILIAR WITH THIS ACFT BUT THE STORMSCOPE OUTPUT TO THE GPS STILL APPEARED TO BE FUNCTIONING. I NOTICED THAT THE AMMETER READING APPEARED TO BE LOW; THOUGH IT WAS ABOVE ZERO AND THE ALTERNATOR ANNUNCIATOR WAS NOT ILLUMINATED. I TESTED THE ALTERNATOR ANNUNCIATOR BULB (AS I HAD DONE BEFORE FLT) TO MAKE SURE. AS WE WERE IN THE CLASS B AIRSPACE; THE EHSI INDICATED THAT THE INVERTER FREQ WAS TOO LOW. I THEN NOTICED THAT; ALTHOUGH THERE WAS NO AUTOPLT INSTALLED AND IT WAS PLACARDED INOP; THE AUTOPLT ANNUNCIATORS (PRESUMABLY DRIVEN BY THE GPS UNIT WHICH WAS INSTALLED) WERE ALL FLASHING. I ASSUMED THAT THERE WAS SOMETHING WRONG WITH THE EHSI AND THAT ITS OUTPUT TO THE GPS UNIT WAS FAULTY. I DID NOT DRAW A CONNECTION WITH THE PREVIOUS STORMSCOPE FAILURE NOR DID I DECIDE TO TURN BACK TO VFR CONDITIONS. AS I WAS BEING VECTORED; THE EHSI WENT BLANK AND THEN REBOOTED. IT CAME BACK FOR SEVERAL SECONDS AND THEN REBOOTED AGAIN. I MISSED A FEW ATC CALLS AT THIS TIME AND WAS WARNED THAT I WAS HEADED FOR A RESTR AREA. I CORRECTED BY TURNING WITH REF TO THE MAGNETIC COMPASS. I WAS IN VMC AT THE TIME. I DETERMINED AT THIS TIME THAT THE AMMETER READING WAS VERY LOW AND ALMOST ON ZERO. I INFORMED ATC THAT MY DIRECTIONAL GYRO HAD FAILED AND I REQUESTED NO-GYRO VECTORS. WHILE I WAS IN VMC AND COULD TURN WITHOUT TOO MUCH DANGER; SPECIFIC HDGS WITH A MAGNETIC COMPASS ARE TOO CHALLENGING WHILE TRYING TO DEAL WITH SUCH A SITUATION. I WAS VECTORED TO THE LOC COURSE FOR THE ILS AT ZZZ1. I WAS INSTRUCTED TO DSND TO 3500 FT MSL BUT REQUESTED TO REMAIN AT 4000 FT MSL. THE TOPS WERE SLIGHTLY BELOW THAT LEVEL; THOUGH I DID NOT TELL ATC WHY I REQUESTED 4000 FT. WHEN I WAS CLOSE TO THE LOC COURSE; I WAS CLRED FOR THE APCH THOUGH I DID NOT RECEIVE A NO-GYRO VECTOR ONTO THE FINAL APCH COURSE. THIS WAS REALLY THE MOST CRITICAL TURN AND I WAS SURPRISED THAT I HAD TO MAKE IT MYSELF. I FLEW SLIGHTLY THROUGH THE FINAL APCH COURSE BEFORE REALIZING THAT I WAS NOT GOING TO GET THE START TURN/STOP TURN INSTRUCTIONS. THE FIRST APCH WAS BOTCHED RIGHT AS I REACHED THE TOPS AND ATC CANCELED MY CLRNC AND HAD ME CLB AND VECTORED ME BACK AROUND. AT THIS POINT I REMEMBERED THE PARTIAL-PANEL SCREEN ON THE GARMIN 296 THAT WAS MOUNTED ON THE YOKE. THIS PROVED TO BE AN AMAZING ASSET ON THE SECOND APCH. I WAS VECTORED BACK AROUND ONTO THE APCH AND TOLD ATC WHY I WANTED TO STAY AT 4000 FT. I ASKED TO TURN OFF MY XPONDER TO SAVE BATTERY PWR BUT SHE INFORMED ME THAT I COULDN'T BE VECTORED IN THAT CASE. SHE VECTORED ME ONTO THE LOC FURTHER OUT AND I TURNED ON COURSE. AT THIS TIME MY GARMIN 430; WHICH I WAS USING TO COM WITH ATC; REBOOTED. I WAS ALREADY USING MY SECOND NAV RADIO FOR THE LOC AND GS SINCE THE EHSI (WHICH IS CONNECTED TO THE 430) WAS DEAD. I DECIDED TO TURN OFF THE 430 AND USE COM 2 AND NAV 2. I ASKED ATC FOR HER FREQ. THERE WAS SOME CONFUSION ABOUT WHETHER I WAS ASKING FOR THE LOC FREQ; BUT SHE EVENTUALLY TOLD ME THE FREQ WE WERE USING TO COM (WHICH I COULD NOT READ OFF COM 1 BECAUSE IT WAS IN THE PROCESS OF REBOOTING; THOUGH IT SEEMED TO SEND AND RECEIVE FINE). ONCE ESTABLISHED AND DSNDING INTO THE CLOUD TOPS AT 3700 FT MSL; I USED THE GARMIN 296 AS A PSEUDO HSI. I DIDN'T FLY THE BEST APCH EVER; BUT THE NEEDLES NEVER WERE MORE THAN ABOUT 1/2 SCALE DEFLECTION. ONCE I GOT MY SCAN OF THE NORMAL INSTS TO INCLUDE THE HANDHELD GPS; I GOT THE NEEDLES CTRED AND WAS DOING OK BEFORE BREAKING OUT AT 2000 FT MSL. THE TWR ASKED IF I HAD THE FIELD IN SIGHT. I REPLIED THAT I DID AND WAS CLRED TO LAND. SHORTLY THEREAFTER; THE SPEAKER MADE A BAD BUZZING SOUND. CONCERNED THAT THE AVIONICS MAY BE DAMAGED BY LOW VOLTAGE; I TURNED OFF THE AVIONICS MASTER AND EVERYTHING EXCEPT THE FUEL PUMP. I FOLLOWED THE VISUAL GS INDICATOR AND LANDED UNEVENTFULLY. I TAXIED OFF THE RWY AND LOOKED AT THE TWR AND SAW A SOLID GREEN LIGHT. I LOOKED DOWN TO RETRACT THE MANUAL FLAPS AND TURN OFF THE FUEL PUMP AND THE MASTER SWITCH. I LOOKED UP AND SAW A FLASHING GREEN LIGHT AND THEN REALIZED THAT THE EARLIER SOLID GREEN WAS AN ERROR ON THE TWR'S PART; THOUGH I CERTAINLY WAS NOT GOING TO FOLLOW THEIR INSTRUCTIONS AND TAKE OFF AGAIN. I TAXIED AND PARKED UNEVENTFULLY. AFTER EXITING THE AIRPLANE; I NOTICED THAT THE ALTERNATOR BELT WAS QUITE LOOSE AND COULD BE TURNED BY HAND. THE MECH AT THE FLYING CLUB I RENTED FROM HAD JUST RETURNED THE AIRPLANE TO SVC AND HE MENTIONED BEFORE I LEFT THAT HE HAD CHANGED THE OIL AND THE ALTERNATOR BELT. I FORGOT HIS COMMENT UNTIL AFTER LNDG. I SHOULD HAVE REMEMBERED IT WHEN THE STORMSCOPE FAILED. I SHOULD HAVE ASKED THE APCH CTLR FOR THE NEAREST VFR WX (OR; MORE PRECISELY; THE NEAREST ARPT WITH NO CEILING SINCE ZZZ1 WAS TECHNICALLY VFR WITH AN APPROX 2000 FT CEILING). IF I LOST ALL PWR ABOVE THE CLOUDS THEN MY LOC AND GS NEEDLES WOULD HAVE BEEN USELESS. I COULD HAVE DONE A NORDO LOC APCH USING THE HANDHELD GPS (WHICH IS NOT LEGAL BUT PROBABLY REASONABLE UNDER 91.3 IN SUCH AN EMER) OR GONE TO ANOTHER ARPT (PROBABLY A BETTER IDEA). FIGURING OUT THAT ALTERNATE WOULD HAVE BEEN PRUDENT (AND I HAD NOT FILED AN ALTERNATE BECAUSE THE MARINE LAYER WAS SUPPOSED TO HAVE BROKEN UP BY THIS TIME). I ALSO SHOULD HAVE ANNOUNCED MY INTENTIONS IN CASE OF A MISSED APCH (IF BELOW THE CLOUDS; MAINTAIN VFR AND ENTER THE RI PATTERN TO TRY AGAIN). I THINK THAT THEY COULD HAVE FIGURED THAT OUT BUT IT DOESN'T HURT TO BE EXPLICIT. I WAS RELATIVELY UNFAMILIAR WITH THE AMMETER INSTALLED IN THIS PIPER. THE CESSNA AMMETERS THAT I USUALLY SEE HAVE A CLR CHARGE/DISCHARGE INDICATION. THIS PIPER AMMETER BASICALLY REQUIRES THE PLT TO KNOW THE NORMAL INDICATION AND JUDGE WHETHER THE NEEDLE IS ABOVE OR BELOW THAT POINT. I PREFER THE CESSNA CHARGE/DISCHARGE METER WHICH SHOULD NORMALLY POINT AT OR NEAR ZERO SINCE THAT DOESN'T REQUIRE KNOWLEDGE OF THE PWR DRAWN BY VARIOUS LOADS. THE ATC PEOPLE WERE EXCELLENT AND THE HANDHELD GPS WAS A VALUABLE ASSET WITH ITS DEPICTION OF THE HSI AND TURN COORDINATOR (THOUGH I AM HAPPY THAT THE ACFT'S TURN COORDINATOR NEVER DIED). I AM GLAD THAT THE ACFT HAD AN EHSI INSTEAD OF A NORMAL HSI OR DIRECTIONAL GYRO. THE FAILURE OF THE EHSI MEANT THAT THE SCREEN WAS ENTIRELY BLANK. WHILE I DID CARRY SOME INST COVERS AND COULD HAVE RETRIEVED THEM; IT WAS 1 LESS THING TO WORRY ABOUT. HAVING THE INST BE COMPLETELY DARK AVOIDED ANY CONFUSION WHERE I WAS LOOKING AT INCORRECT INFO. SHOULD I HAVE DONE THE APCH INTO ZZZ1; I THINK THAT IT WAS NOT VERY HAZARDOUS BECAUSE MY ATTITUDE INDICATOR WORKED PROPERLY; I WAS IN VMC UNTIL ESTABLISHED (SO I ONLY NEEDED TO FLY A STRAIGHT LINE DSCNT); IT WAS AN ILS (WHICH IS EASIER THAN AN NDB OR SOME OTHER NON-PRECISION APCHS); THE CEILING WAS ABOUT 2000 FT AGL; AND I HAD LIMITED BATTERY LIFE REMAINING. IF THE ELECTRICAL SYS HAD TOTALLY FAILED; I DID HAVE ENOUGH FUEL TO GET TO A VFR ARPT WITH RESERVES. I DID NOT WANT TO TRANSIT THE CLASS B WITH NO ELECTRICAL SYS (NO XPONDER AND NO ATC COM). SHOULD I HAVE DECLARED AN EMER EXPLICITLY? ATC WAS WELL AWARE OF MY SITUATION AND I HAD DESCRIBED THE NATURE OF MY PROB AND THE POTENTIAL IMPACTS. THE TWR WAS INFORMED THAT MY RADIO MIGHT DIE ON THE APCH. I THINK THAT DECLARING AN EMER WOULD HAVE BEEN APPROPRIATE THOUGH IT WAS NOT REQUIRED AND SO I DID NOT DO SO. I ALSO DID NOT WANT TO PANIC MY PAX WITH THAT WORD AND DESCRIPTIONS OF THEM AS 'SOULS' (WHICH I FIND TO BE A GRIM TERM). SHOULD I HAVE NOTICED THE FAILURE EARLIER? DEFINITELY. I WAS EXPECTING AN ALTERNATOR FAILURE TO BE ACCOMPANIED BY AN ANNUNCIATION AND PERHAPS SOME LARGE EVENT. I'M MUCH MORE AWARE OF THIS GRADUAL CHAIN OF EVENTS THAN BEFORE. I'M GLAD THAT IT ALL TURNED OUT FINE AND I CAN LEARN FROM THE EXPERIENCE.

Data retrieved from NASA's ASRS site as of May 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.