What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On July 3, 2023, the pilot in command (PIC) and one passenger departed wiscasset airport, wiscasset, Maine (kiwi) to a planned destination of northeast philadelphia airport, philadelphia, Pennsylvania, (kpne) on a 14 CFR part 91 personal flight. The pilot stated this flight took place approximately 10 hours after the most recent 100 hour maintenance inspection. After the aircraft departed kiwi, the PIC stated they climbed to 6,000 feet and remained there are cruise for approximately 45 minutes. After a requested altitude change, the PIC climbed to 6,200 feet and remained there for approximately 10 minutes when the PIC heard a loud “pop” and the pax pointed out the digital tachometer had suddenly failed and lost power. The PIC stated they went to call approach to alert them of the issue and start planning a landing and when they noticed the garmin 430 flashed multiple times and then lost power along with the transponder, audio panel, ammeter/voltmeter, lower garmin G5 and turn coordinator (electrical). The PIC stated almost immediately after this smoke started to come into the cabin from behind the garmin 430 unit as well as from behind the left analog gauge cluster and under right side of dashboard panel. The PIC stated the smell of the smoke was indictable of an electrical burn as noted by the smell of burning insulation and white smoke. The electrical master and alternator and radio master switches were immediately shut off and multiple breakers had been tripped at this point. The PIC opened the pilot side window and got a rush of smoke into the cabin, a large amount of heat was noticed from the pax under the right side of the dashboard by their knees. The PIC found that Worcester Regional Airport, Worcester, Massachusetts, (korh) to the southeast at 12 nautical miles was most suitable for landing. PIC executed an emergency gear extension and landed on runway 33. Aircraft was met by emergency services and pic/pax deplaned without injury. Subsequent inspection by certificated mechanics found and replaced the following damaged components and accessories: aircraft battery, voltage regulator, alternator, damaged wire from voltage regulator to alternator, damaged alternator return line from firewall forward, five (5) feet of 12 gauge wire and three (3) feet of 4 gauge wire. At this time the following are inoperative and require further troubleshooting: oil temp gauge, both fuel quantity gauges, tachometer, and the com and navigation radios.
As the FAA filed it
ON JULY 3, 2023, THE PILOT IN COMMAND (PIC) AND ONE PASSENGER DEPARTED WISCASSET AIRPORT, WISCASSET, MAINE (KIWI) TO A PLANNED DESTINATION OF NORTHEAST PHILADELPHIA AIRPORT, PHILADELPHIA, PENNSYLVANIA, (KPNE) ON A 14 CFR PART 91 PERSONAL FLIGHT. THE PILOT STATED THIS FLIGHT TOOK PLACE APPROXIMATELY 10 HOURS AFTER THE MOST RECENT 100 HOUR MAINTENANCE INSPECTION. AFTER THE AIRCRAFT DEPARTED KIWI, THE PIC STATED THEY CLIMBED TO 6,000 FEET AND REMAINED THERE ARE CRUISE FOR APPROXIMATELY 45 MINUTES. AFTER A REQUESTED ALTITUDE CHANGE, THE PIC CLIMBED TO 6,200 FEET AND REMAINED THERE FOR APPROXIMATELY 10 MINUTES WHEN THE PIC HEARD A LOUD “POP” AND THE PAX POINTED OUT THE DIGITAL TACHOMETER HAD SUDDENLY FAILED AND LOST POWER. THE PIC STATED THEY WENT TO CALL APPROACH TO ALERT THEM OF THE ISSUE AND START PLANNING A LANDING AND WHEN THEY NOTICED THE GARMIN 430 FLASHED MULTIPLE TIMES AND THEN LOST POWER ALONG WITH THE TRANSPONDER, AUDIO PANEL, AMMETER/VOLTMETER, LOWER GARMIN G5 AND TURN COORDINATOR (ELECTRICAL). THE PIC STATED ALMOST IMMEDIATELY AFTER THIS SMOKE STARTED TO COME INTO THE CABIN FROM BEHIND THE GARMIN 430 UNIT AS WELL AS FROM BEHIND THE LEFT ANALOG GAUGE CLUSTER AND UNDER RIGHT SIDE OF DASHBOARD PANEL. THE PIC STATED THE SMELL OF THE SMOKE WAS INDICTABLE OF AN ELECTRICAL BURN AS NOTED BY THE SMELL OF BURNING INSULATION AND WHITE SMOKE. THE ELECTRICAL MASTER AND ALTERNATOR AND RADIO MASTER SWITCHES WERE IMMEDIATELY SHUT OFF AND MULTIPLE BREAKERS HAD BEEN TRIPPED AT THIS POINT. THE PIC OPENED THE PILOT SIDE WINDOW AND GOT A RUSH OF SMOKE INTO THE CABIN, A LARGE AMOUNT OF HEAT WAS NOTICED FROM THE PAX UNDER THE RIGHT SIDE OF THE DASHBOARD BY THEIR KNEES. THE PIC FOUND THAT WORCESTER REGIONAL AIRPORT, WORCESTER, MASSACHUSETTS, (KORH) TO THE SOUTHEAST AT 12 NAUTICAL MILES WAS MOST SUITABLE FOR LANDING. PIC EXECUTED AN EMERGENCY GEAR EXTENSION AND LANDED ON RUNWAY 33. AIRCRAFT WAS MET BY EMERGENCY SERVICES AND PIC/PAX DEPLANED WITHOUT INJURY. SUBSEQUENT INSPECTION BY CERTIFICATED MECHANICS FOUND AND REPLACED THE FOLLOWING DAMAGED COMPONENTS AND ACCESSORIES: AIRCRAFT BATTERY, VOLTAGE REGULATOR, ALTERNATOR, DAMAGED WIRE FROM VOLTAGE REGULATOR TO ALTERNATOR, DAMAGED ALTERNATOR RETURN LINE FROM FIREWALL FORWARD, FIVE (5) FEET OF 12 GAUGE WIRE AND THREE (3) FEET OF 4 GAUGE WIRE. AT THIS TIME THE FOLLOWING ARE INOPERATIVE AND REQUIRE FURTHER TROUBLESHOOTING: OIL TEMP GAUGE, BOTH FUEL QUANTITY GAUGES, TACHOMETER, AND THE COM AND NAVIGATION RADIOS.