Narrative:

On feb/sun/97, I flew with 2 passenger from lwm to rkd on a sight-seeing flight. During the training flight, communication #1 had some audio distortion, and what seemed to be a marginal squelch setting. I used communication #2 as my primary radio for the flight. We were using a battery-pwred intercom for the pilot and both passenger. I was using a yoke-mounted VFR GPS (garmin 195). The GPS was running on a cigarette-lighter plug interface to the aircraft electrical system, with its internal rechargeable battery as backup. The battery was fully charged at the start of the day, it has a 7 hour life-span with no back-light. I had a hand-held radio (icom ica-21) in my flight bag. It started the day with a fully charged battery as well. The flight northward commenced at XY30 local, and was uneventful except for the #1 communication radio acting up. We landed. On the sbound flight at 4500 ft MSL, navigation was visual, VOR and GPS. We were receiving advisories from ATC, were squawking a code and were in contact with brunswick, portland, and manchester approach controllers. Our electrical failure occurred while we were in contact with manchester approach 125.05. We were flying into a sunset, and it was obvious that the landing was going to effectively be a night landing. The sbound flight proceeded normally until failure of radio #1 less than 20 mi north of psm. The display began flashing erratically, I concluded that #1 radio failed. I shut off radio #1. Manchester approach reported loss of my squawk, and requested that I recycle my transponder. I noticed that the light on the transponder had been remaining on solidly, and it was dim. Upon recycling the transponder, manchester approach still did not receive my squawk. It was at this time that radio #2 failed in exactly the same way as #1. I turned off radio #2. I turned toward psm which was in sight and at about 4 mi. I set my transponder for 7600 and pressed identify. No light came on and I realized that the transponder was out. It was then that I checked the alternator (generator?) meter for charging current and it read zero. I interpreted this as an alternator failure, and realized that we had only battery power left. I turned off all electricals except the tail strobe. I asked my wife, who was in the back seat to give me the hand-held radio. I tried calling manchester approach on 125.05, but received no response. I was almost on top of psm at 4500 ft MSL at this point, so I called psm tower, and asked them to relay my situation to approach. I concluded that there was effectively no difference in safety landing at psm or landing at lwm about 12 mins away. I informed manchester approach of my intentions, and they asked to be informed when I switched to lwm tower frequency. At this time, I looked down at my GPS which was on the HSI display page. The waypoint it was navigating to was lwm, which is correct for lawrence airport. It indicated a ground track required of about 240 degrees. I turned directly toward the waypoint and pressed 'goto' and 'enter' to create a new radial to the waypoint. The default waypoint in the goto screen is the current goto waypoint, this is a quick way to reset the course line. Creating the new radial re- centered the needle, and I began carefully navigating directly to lwm. I used a feature of the garmin 195 which gives vertical navigation information, and began a descent of 500 FPM based upon GPS information. I thought I had idented the airport vicinity at 12 O'clock, but this later turned out to be rockingham park, a racetrack. I later realized that this decision-making process along with the navigational issues caused me to not complete my full landing checklist. I landed without the mixture in the full rich position. This was a procedural error on my part. The HSI screen of the GPS was giving me erroneous information, but the map screen was correct. I realized that the HSI display was steering me on a parallel track, but 5.6 mi to the right (northwest) of the correct course. I remember that when I switched to the map display, I looked for the lubber line on the strip compass. On the garmin 195, the lubber line always indicates the ground track to the current waypoint. The lubber line was nowhere to be seen, even though the HSI display indicated my waypoint was dead ahead. I believe that there is a software bug in the garmin 195 (software version 2.01) specifically related to the HSI display. I visually picked up the airport off the left wing and turned to enter a wide downwind for runway 32 at lwm. I announced my turn to final on the hand-held. The lwm tower controller (controller #1) cleared the other aircraft for departure. This was a night landing and one with a complete electrical failure. I think it would have been prudent to hold up the aircraft on the ground until I was down and out of the pattern. I had not declared an emergency. I started the flight with 3 levels of navigation: visual, GPS, VOR. After the electrical system failure, I seemed to get 'tunnel vision' on the GPS, effectively eliminating any xchk with my visual navigation. I think controller #2 had a hard time judging my distance when I was on final approach. I had only a tail strobe visible. The a&P mechanic verified that I had experienced a voltage regulator failure. The alternator itself was rebuilt within the last yr. Garmin verified that their software updates (they are up to 2.04, my unit was 2.01) had corrected bugs in the HSI display. I have not received the unit back from garmin as of this writing.

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Original NASA ASRS Text

Title: PA28 PVT PLT SUFFERS A LOSS OF HIS ALTERNATOR BUT DELAYS IN THE RECOGNITION OF HIS PROB. AFTER DEALING WITH THAT, HE RUNS INTO A PROB USING HIS GPS WHICH IS NOW ON BATTERY PWR.

Narrative: ON FEB/SUN/97, I FLEW WITH 2 PAX FROM LWM TO RKD ON A SIGHT-SEEING FLT. DURING THE TRAINING FLT, COM #1 HAD SOME AUDIO DISTORTION, AND WHAT SEEMED TO BE A MARGINAL SQUELCH SETTING. I USED COM #2 AS MY PRIMARY RADIO FOR THE FLT. WE WERE USING A BATTERY-PWRED INTERCOM FOR THE PLT AND BOTH PAX. I WAS USING A YOKE-MOUNTED VFR GPS (GARMIN 195). THE GPS WAS RUNNING ON A CIGARETTE-LIGHTER PLUG INTERFACE TO THE ACFT ELECTRICAL SYS, WITH ITS INTERNAL RECHARGEABLE BATTERY AS BACKUP. THE BATTERY WAS FULLY CHARGED AT THE START OF THE DAY, IT HAS A 7 HR LIFE-SPAN WITH NO BACK-LIGHT. I HAD A HAND-HELD RADIO (ICOM ICA-21) IN MY FLT BAG. IT STARTED THE DAY WITH A FULLY CHARGED BATTERY AS WELL. THE FLT NORTHWARD COMMENCED AT XY30 LCL, AND WAS UNEVENTFUL EXCEPT FOR THE #1 COM RADIO ACTING UP. WE LANDED. ON THE SBOUND FLT AT 4500 FT MSL, NAV WAS VISUAL, VOR AND GPS. WE WERE RECEIVING ADVISORIES FROM ATC, WERE SQUAWKING A CODE AND WERE IN CONTACT WITH BRUNSWICK, PORTLAND, AND MANCHESTER APCH CTLRS. OUR ELECTRICAL FAILURE OCCURRED WHILE WE WERE IN CONTACT WITH MANCHESTER APCH 125.05. WE WERE FLYING INTO A SUNSET, AND IT WAS OBVIOUS THAT THE LNDG WAS GOING TO EFFECTIVELY BE A NIGHT LNDG. THE SBOUND FLT PROCEEDED NORMALLY UNTIL FAILURE OF RADIO #1 LESS THAN 20 MI N OF PSM. THE DISPLAY BEGAN FLASHING ERRATICALLY, I CONCLUDED THAT #1 RADIO FAILED. I SHUT OFF RADIO #1. MANCHESTER APCH RPTED LOSS OF MY SQUAWK, AND REQUESTED THAT I RECYCLE MY XPONDER. I NOTICED THAT THE LIGHT ON THE XPONDER HAD BEEN REMAINING ON SOLIDLY, AND IT WAS DIM. UPON RECYCLING THE XPONDER, MANCHESTER APCH STILL DID NOT RECEIVE MY SQUAWK. IT WAS AT THIS TIME THAT RADIO #2 FAILED IN EXACTLY THE SAME WAY AS #1. I TURNED OFF RADIO #2. I TURNED TOWARD PSM WHICH WAS IN SIGHT AND AT ABOUT 4 MI. I SET MY XPONDER FOR 7600 AND PRESSED IDENT. NO LIGHT CAME ON AND I REALIZED THAT THE XPONDER WAS OUT. IT WAS THEN THAT I CHKED THE ALTERNATOR (GENERATOR?) METER FOR CHARGING CURRENT AND IT READ ZERO. I INTERPRETED THIS AS AN ALTERNATOR FAILURE, AND REALIZED THAT WE HAD ONLY BATTERY PWR LEFT. I TURNED OFF ALL ELECTRICALS EXCEPT THE TAIL STROBE. I ASKED MY WIFE, WHO WAS IN THE BACK SEAT TO GIVE ME THE HAND-HELD RADIO. I TRIED CALLING MANCHESTER APCH ON 125.05, BUT RECEIVED NO RESPONSE. I WAS ALMOST ON TOP OF PSM AT 4500 FT MSL AT THIS POINT, SO I CALLED PSM TWR, AND ASKED THEM TO RELAY MY SIT TO APCH. I CONCLUDED THAT THERE WAS EFFECTIVELY NO DIFFERENCE IN SAFETY LNDG AT PSM OR LNDG AT LWM ABOUT 12 MINS AWAY. I INFORMED MANCHESTER APCH OF MY INTENTIONS, AND THEY ASKED TO BE INFORMED WHEN I SWITCHED TO LWM TWR FREQ. AT THIS TIME, I LOOKED DOWN AT MY GPS WHICH WAS ON THE HSI DISPLAY PAGE. THE WAYPOINT IT WAS NAVING TO WAS LWM, WHICH IS CORRECT FOR LAWRENCE ARPT. IT INDICATED A GND TRACK REQUIRED OF ABOUT 240 DEGS. I TURNED DIRECTLY TOWARD THE WAYPOINT AND PRESSED 'GOTO' AND 'ENTER' TO CREATE A NEW RADIAL TO THE WAYPOINT. THE DEFAULT WAYPOINT IN THE GOTO SCREEN IS THE CURRENT GOTO WAYPOINT, THIS IS A QUICK WAY TO RESET THE COURSE LINE. CREATING THE NEW RADIAL RE- CTRED THE NEEDLE, AND I BEGAN CAREFULLY NAVING DIRECTLY TO LWM. I USED A FEATURE OF THE GARMIN 195 WHICH GIVES VERT NAV INFO, AND BEGAN A DSCNT OF 500 FPM BASED UPON GPS INFO. I THOUGHT I HAD IDENTED THE ARPT VICINITY AT 12 O'CLOCK, BUT THIS LATER TURNED OUT TO BE ROCKINGHAM PARK, A RACETRACK. I LATER REALIZED THAT THIS DECISION-MAKING PROCESS ALONG WITH THE NAVIGATIONAL ISSUES CAUSED ME TO NOT COMPLETE MY FULL LNDG CHKLIST. I LANDED WITHOUT THE MIXTURE IN THE FULL RICH POS. THIS WAS A PROCEDURAL ERROR ON MY PART. THE HSI SCREEN OF THE GPS WAS GIVING ME ERRONEOUS INFO, BUT THE MAP SCREEN WAS CORRECT. I REALIZED THAT THE HSI DISPLAY WAS STEERING ME ON A PARALLEL TRACK, BUT 5.6 MI TO THE R (NW) OF THE CORRECT COURSE. I REMEMBER THAT WHEN I SWITCHED TO THE MAP DISPLAY, I LOOKED FOR THE LUBBER LINE ON THE STRIP COMPASS. ON THE GARMIN 195, THE LUBBER LINE ALWAYS INDICATES THE GND TRACK TO THE CURRENT WAYPOINT. THE LUBBER LINE WAS NOWHERE TO BE SEEN, EVEN THOUGH THE HSI DISPLAY INDICATED MY WAYPOINT WAS DEAD AHEAD. I BELIEVE THAT THERE IS A SOFTWARE BUG IN THE GARMIN 195 (SOFTWARE VERSION 2.01) SPECIFICALLY RELATED TO THE HSI DISPLAY. I VISUALLY PICKED UP THE ARPT OFF THE L WING AND TURNED TO ENTER A WIDE DOWNWIND FOR RWY 32 AT LWM. I ANNOUNCED MY TURN TO FINAL ON THE HAND-HELD. THE LWM TWR CTLR (CTLR #1) CLRED THE OTHER ACFT FOR DEP. THIS WAS A NIGHT LNDG AND ONE WITH A COMPLETE ELECTRICAL FAILURE. I THINK IT WOULD HAVE BEEN PRUDENT TO HOLD UP THE ACFT ON THE GND UNTIL I WAS DOWN AND OUT OF THE PATTERN. I HAD NOT DECLARED AN EMER. I STARTED THE FLT WITH 3 LEVELS OF NAV: VISUAL, GPS, VOR. AFTER THE ELECTRICAL SYS FAILURE, I SEEMED TO GET 'TUNNEL VISION' ON THE GPS, EFFECTIVELY ELIMINATING ANY XCHK WITH MY VISUAL NAV. I THINK CTLR #2 HAD A HARD TIME JUDGING MY DISTANCE WHEN I WAS ON FINAL APCH. I HAD ONLY A TAIL STROBE VISIBLE. THE A&P MECH VERIFIED THAT I HAD EXPERIENCED A VOLTAGE REGULATOR FAILURE. THE ALTERNATOR ITSELF WAS REBUILT WITHIN THE LAST YR. GARMIN VERIFIED THAT THEIR SOFTWARE UPDATES (THEY ARE UP TO 2.04, MY UNIT WAS 2.01) HAD CORRECTED BUGS IN THE HSI DISPLAY. I HAVE NOT RECEIVED THE UNIT BACK FROM GARMIN AS OF THIS WRITING.

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.