Narrative:

Loss of electrical power led to intermittent contact with approach. Full power (electrical) loss led to inability to extend electric landing gear and electric flaps. Phase 1: in retrospect I had a clue that I had an electrical problem, but did not recognize it because of recurring issues with the new autoplt I had installed and the new face/displays installed on my navigation/communication. The autoplt had been in for service several times. During the last part of the en route flight to philadelphia international airport on an IFR flight plan the autoplt altitude hold refused to hold. This happened once before, so I disengaged it. Approximately 20 mi from philadelphia international the radio I had just had repaired went out. I reset a fuse -- it went back on and I proceeded inbound. I alerted approach that I had a bad radio and he cleared me direct to philadelphia international airport. He then handed me off to another approach frequency. I checked in and that was the end of communication -- at least reception by me. Since I was on an IFR flight plan and the conditions were VFR I decided to continue into philadelphia since it was the closest airport. I was cleared direct (last IFR communication). I had no electrical power -- the radio and the autoplt had tried to warn me of that earlier. Without electrical power, I was unable to conventionally lower the gear or the flaps. I slowed the airplane, made a slow turn to bleed off speed, lowered the landing gear, cycled the master and the lights to see if I could get a green gear indicator, to no avail. I pulled the gear lever to see if it was tight and pushed hard one more time to ensure it was down and locked. I landed the plane smoothly and rolled out. During the rollout I felt I was slowly sinking and realized the gear was folding under me. The aircraft smoothly lowered -- the propeller struck. I turned off the master and ignition key and tried to keep the plane centered. Fortunately the plane was just right of runway centerline and moving straight as the nose and main gear fully collapsed. Lessons learned: even if you have had recurring problem (irritants) with non critical equipment (altitude hold) look further as it may be caused by another root cause than the last problem. Carry a hand-held in order to communicate with center approach, tower or ground personnel. Without electrical not sure what else I could have done to verify gear locked -- no power.

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Original NASA ASRS Text

Title: PA24-250 HAS ELECTRICAL FAILURE FOLLOWED LATER BY A GEAR COLLAPSE AFTER LNDG.

Narrative: LOSS OF ELECTRICAL PWR LED TO INTERMITTENT CONTACT WITH APCH. FULL PWR (ELECTRICAL) LOSS LED TO INABILITY TO EXTEND ELECTRIC LNDG GEAR AND ELECTRIC FLAPS. PHASE 1: IN RETROSPECT I HAD A CLUE THAT I HAD AN ELECTRICAL PROB, BUT DID NOT RECOGNIZE IT BECAUSE OF RECURRING ISSUES WITH THE NEW AUTOPLT I HAD INSTALLED AND THE NEW FACE/DISPLAYS INSTALLED ON MY NAV/COM. THE AUTOPLT HAD BEEN IN FOR SVC SEVERAL TIMES. DURING THE LAST PART OF THE ENRTE FLT TO PHILADELPHIA INTL ARPT ON AN IFR FLT PLAN THE AUTOPLT ALT HOLD REFUSED TO HOLD. THIS HAPPENED ONCE BEFORE, SO I DISENGAGED IT. APPROX 20 MI FROM PHILADELPHIA INTL THE RADIO I HAD JUST HAD REPAIRED WENT OUT. I RESET A FUSE -- IT WENT BACK ON AND I PROCEEDED INBOUND. I ALERTED APCH THAT I HAD A BAD RADIO AND HE CLRED ME DIRECT TO PHILADELPHIA INTL ARPT. HE THEN HANDED ME OFF TO ANOTHER APCH FREQ. I CHKED IN AND THAT WAS THE END OF COM -- AT LEAST RECEPTION BY ME. SINCE I WAS ON AN IFR FLT PLAN AND THE CONDITIONS WERE VFR I DECIDED TO CONTINUE INTO PHILADELPHIA SINCE IT WAS THE CLOSEST ARPT. I WAS CLRED DIRECT (LAST IFR COM). I HAD NO ELECTRICAL PWR -- THE RADIO AND THE AUTOPLT HAD TRIED TO WARN ME OF THAT EARLIER. WITHOUT ELECTRICAL PWR, I WAS UNABLE TO CONVENTIONALLY LOWER THE GEAR OR THE FLAPS. I SLOWED THE AIRPLANE, MADE A SLOW TURN TO BLEED OFF SPD, LOWERED THE LNDG GEAR, CYCLED THE MASTER AND THE LIGHTS TO SEE IF I COULD GET A GREEN GEAR INDICATOR, TO NO AVAIL. I PULLED THE GEAR LEVER TO SEE IF IT WAS TIGHT AND PUSHED HARD ONE MORE TIME TO ENSURE IT WAS DOWN AND LOCKED. I LANDED THE PLANE SMOOTHLY AND ROLLED OUT. DURING THE ROLLOUT I FELT I WAS SLOWLY SINKING AND REALIZED THE GEAR WAS FOLDING UNDER ME. THE ACFT SMOOTHLY LOWERED -- THE PROP STRUCK. I TURNED OFF THE MASTER AND IGNITION KEY AND TRIED TO KEEP THE PLANE CTRED. FORTUNATELY THE PLANE WAS JUST R OF RWY CTRLINE AND MOVING STRAIGHT AS THE NOSE AND MAIN GEAR FULLY COLLAPSED. LESSONS LEARNED: EVEN IF YOU HAVE HAD RECURRING PROB (IRRITANTS) WITH NON CRITICAL EQUIP (ALT HOLD) LOOK FURTHER AS IT MAY BE CAUSED BY ANOTHER ROOT CAUSE THAN THE LAST PROB. CARRY A HAND-HELD IN ORDER TO COMMUNICATE WITH CTR APCH, TWR OR GND PERSONNEL. WITHOUT ELECTRICAL NOT SURE WHAT ELSE I COULD HAVE DONE TO VERIFY GEAR LOCKED -- NO PWR.

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.