Narrative:

Descending; at about FL240; we experienced a failure of AC bus 2. Simultaneously; we briefly smelled an electrical odor; briefly lost pressurization; and several other associated failures occurred. We ran the AC bus 2 message checklist -- which called for a GEN2 reset -- and successfully recovered normal electrical operation. Approximately 30 seconds later; we experienced a more serious electrical failure. The pfd's; mfd's; FMS; and EICAS screens all started to blink on and off and we could hear electrical relays clicking. The air driven generator (air-driven generator) deployed; AC bus 1 failed; and AC bus 2 failed; but thankfully; came back on line. Both AC autotransfer functions showed that they had failed. I immediately declared an emergency with center. At a loss to understand the situation; we quickly called our airline's maintenance control and received assistance. Eventually we were able to recover use of all AC busses except for the AC service and utility busses. This left the cabin without lights; but all major aircraft systems were operational. We made an uneventful landing several minutes later. Upon reaching the gate; however; we again smelled the electrical odor and I decided to shut down the aircraft. The passenger deplaned in a normal fashion with aid from the emergency lights. Maintenance quickly found the source of the problem. An electrical component in the avionics bay had severely overheated; leaving a charred area of about 2 cubic ft. Several wires and nearby components in the area had been charred. Upon seeing the damage; I quickly realized that we were extremely lucky to have avoided a much more serious emergency. Callback conversation with reporter revealed the following information: reporter stated that there was extremely heavy rain at the departure airport and that a 'universal fit' jetway was used; which did not fit tightly against the fuselage. Reporter stated that 'a lot of water' entered the aircraft in the boarding area. Reporter advised that; after landing; evidence of a lightning strike was noted near the radome. Reporter stated that there was lightning seen on the last leg of the flight; but that the strike could also have occurred on the leg previous to when the electrical problems occurred.

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Original NASA ASRS Text

Title: CL65 FLT CREW EXPERIENCED MULTIPLE ELECTRICAL FAILURES ACCOMPANIED BY AN ELECTRICAL ODOR. EMER DECLARED AND A SUCCESSFUL LNDG WAS MADE.

Narrative: DSNDING; AT ABOUT FL240; WE EXPERIENCED A FAILURE OF AC BUS 2. SIMULTANEOUSLY; WE BRIEFLY SMELLED AN ELECTRICAL ODOR; BRIEFLY LOST PRESSURIZATION; AND SEVERAL OTHER ASSOCIATED FAILURES OCCURRED. WE RAN THE AC BUS 2 MSG CHKLIST -- WHICH CALLED FOR A GEN2 RESET -- AND SUCCESSFULLY RECOVERED NORMAL ELECTRICAL OPERATION. APPROX 30 SECONDS LATER; WE EXPERIENCED A MORE SERIOUS ELECTRICAL FAILURE. THE PFD'S; MFD'S; FMS; AND EICAS SCREENS ALL STARTED TO BLINK ON AND OFF AND WE COULD HEAR ELECTRICAL RELAYS CLICKING. THE ADG (AIR-DRIVEN GENERATOR) DEPLOYED; AC BUS 1 FAILED; AND AC BUS 2 FAILED; BUT THANKFULLY; CAME BACK ON LINE. BOTH AC AUTOTRANSFER FUNCTIONS SHOWED THAT THEY HAD FAILED. I IMMEDIATELY DECLARED AN EMER WITH CENTER. AT A LOSS TO UNDERSTAND THE SITUATION; WE QUICKLY CALLED OUR AIRLINE'S MAINT CTL AND RECEIVED ASSISTANCE. EVENTUALLY WE WERE ABLE TO RECOVER USE OF ALL AC BUSSES EXCEPT FOR THE AC SERVICE AND UTILITY BUSSES. THIS LEFT THE CABIN WITHOUT LIGHTS; BUT ALL MAJOR ACFT SYSTEMS WERE OPERATIONAL. WE MADE AN UNEVENTFUL LNDG SEVERAL MINUTES LATER. UPON REACHING THE GATE; HOWEVER; WE AGAIN SMELLED THE ELECTRICAL ODOR AND I DECIDED TO SHUT DOWN THE ACFT. THE PAX DEPLANED IN A NORMAL FASHION WITH AID FROM THE EMER LIGHTS. MAINT QUICKLY FOUND THE SOURCE OF THE PROB. AN ELECTRICAL COMPONENT IN THE AVIONICS BAY HAD SEVERELY OVERHEATED; LEAVING A CHARRED AREA OF ABOUT 2 CUBIC FT. SEVERAL WIRES AND NEARBY COMPONENTS IN THE AREA HAD BEEN CHARRED. UPON SEEING THE DAMAGE; I QUICKLY REALIZED THAT WE WERE EXTREMELY LUCKY TO HAVE AVOIDED A MUCH MORE SERIOUS EMER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THERE WAS EXTREMELY HEAVY RAIN AT THE DEP ARPT AND THAT A 'UNIVERSAL FIT' JETWAY WAS USED; WHICH DID NOT FIT TIGHTLY AGAINST THE FUSELAGE. RPTR STATED THAT 'A LOT OF WATER' ENTERED THE ACFT IN THE BOARDING AREA. RPTR ADVISED THAT; AFTER LNDG; EVIDENCE OF A LIGHTNING STRIKE WAS NOTED NEAR THE RADOME. RPTR STATED THAT THERE WAS LIGHTNING SEEN ON THE LAST LEG OF THE FLT; BUT THAT THE STRIKE COULD ALSO HAVE OCCURRED ON THE LEG PREVIOUS TO WHEN THE ELECTRICAL PROBS OCCURRED.

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.