Narrative:

At 23000 ft; the 'AC bus 1' then 'left automatic xfer fail' then 'gen 1 off' caution messages appeared. All CRT tubes were flashing on and off. This was followed by the autoplt disconnecting. Then the stabilizer trim; mach trim; and stall fail cautions appeared. The first officer was the PF; the captain declared an emergency and requested vectors to the nearest airport. We received a turn toward ZZZ. We ran the QRH for AC bus 1; left xfer fail; and gen 1 off. Then we completed the QRH for stall fail; stabilizer trim; and mach trim. During the descent the 'EFIS comp mon' caution appeared and the yellow IAS box was over the first officer's airspeed. The captain's and the standby airspds indicated 280 KTS while the first officer's indicated 250 KTS. Per the QRH system (first officer) may have been degraded with right side air data probes affected by AC bus 1 off line. Then at about 11000 ft; the 'ap nu trim' caution appeared. The first officer disconnected the autoplt and hand flew the rest of the flight (quite well; by the way). At this point (on downwind) the captain briefed the approach for the ILS runway 10R at ZZZ. We then ran the descent and approach checklists. The captain again called the flight attendant to confirm the type of landing and the time remaining. We made a normal landing in ZZZ. After monitoring the cabin we elected not to evacuate on the runway as there was no evidence of smoke/fire/damage. We taxied to our gate where we met the ZZZ crash fire rescue equipment chief. He verified there was no abnormal indications in the avionics bay or the aft equipment bay. The passenger were told there was an electrical problem and we needed to land. We then deplaned the passenger. Contract maintenance arrived. After they inspected the left forward portion of the avionics bay; he indicated we had melted wires and an electrical fire at some point. Having seen the damage; it was apparent that we should have completed the QRH procedure for smoke or electrical fire. However; there was some satisfaction to us that the problem had fixed itself by isolating that AC bus and stopping short. We were under the impression there was an electrical failure; not a fire. We strongly believe the problem occurred (after reviewing all the events) because of water on the cockpit and galley floor. There was heavy snow falling at the gate in ZZZ1 and the snow probably melted and leaked down to the electrical equipment. This could be prevented by having a canopy covering the doorway with jetway or something to keep rain/snow outside the airplane. Callback conversation with reporter revealed the following information: the reporter stated the entire #1 AC bus failed and the #1 xfer bus failed. The reporter indicated that from then on; all kinds of failures and fail messages were displayed. The reporter stated the QRH checks were run through for systems that failed but was unaware that a fire was present as no smoke was detected visually. Rptedly; the first officer did smell electrical heat odor but not in amounts that would indicate a fire. The reporter stated the situation has happened before where snow or rain drain into the electrical and electronics bay and caused problems with the systems; adding an effective water barrier or drip shield needs to be in place to protect the electronics bay. Supplemental information from acn 680209: at FL230; all crts went out momentarily; followed immediately by electrical burning smell. Mechanic said there was evidence of a fire in the avionics bay. However; due to the dissipation of the smell in flight; we had no reason to believe there was an actual fire until we were able to look in the avionics bay.

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Original NASA ASRS Text

Title: A CL65 IN CLB AT FL230 DECLARED AN EMER AND DIVERTED DUE TO LOSS OF #1 AC BUS; #1 XFER BUS; AND #1 GEN OFF MESSAGE AND NUMEROUS SYSTEM FAILURES. MAINT FOUND EVIDENCE OF A FIRE IN THE AVIONICS BAY.

Narrative: AT 23000 FT; THE 'AC BUS 1' THEN 'L AUTO XFER FAIL' THEN 'GEN 1 OFF' CAUTION MESSAGES APPEARED. ALL CRT TUBES WERE FLASHING ON AND OFF. THIS WAS FOLLOWED BY THE AUTOPLT DISCONNECTING. THEN THE STAB TRIM; MACH TRIM; AND STALL FAIL CAUTIONS APPEARED. THE FO WAS THE PF; THE CAPT DECLARED AN EMER AND REQUESTED VECTORS TO THE NEAREST ARPT. WE RECEIVED A TURN TOWARD ZZZ. WE RAN THE QRH FOR AC BUS 1; L XFER FAIL; AND GEN 1 OFF. THEN WE COMPLETED THE QRH FOR STALL FAIL; STAB TRIM; AND MACH TRIM. DURING THE DSCNT THE 'EFIS COMP MON' CAUTION APPEARED AND THE YELLOW IAS BOX WAS OVER THE FO'S AIRSPD. THE CAPT'S AND THE STANDBY AIRSPDS INDICATED 280 KTS WHILE THE FO'S INDICATED 250 KTS. PER THE QRH SYSTEM (FO) MAY HAVE BEEN DEGRADED WITH R SIDE AIR DATA PROBES AFFECTED BY AC BUS 1 OFF LINE. THEN AT ABOUT 11000 FT; THE 'AP NU TRIM' CAUTION APPEARED. THE FO DISCONNECTED THE AUTOPLT AND HAND FLEW THE REST OF THE FLT (QUITE WELL; BY THE WAY). AT THIS POINT (ON DOWNWIND) THE CAPT BRIEFED THE APCH FOR THE ILS RWY 10R AT ZZZ. WE THEN RAN THE DSCNT AND APCH CHKLISTS. THE CAPT AGAIN CALLED THE FLT ATTENDANT TO CONFIRM THE TYPE OF LNDG AND THE TIME REMAINING. WE MADE A NORMAL LNDG IN ZZZ. AFTER MONITORING THE CABIN WE ELECTED NOT TO EVACUATE ON THE RWY AS THERE WAS NO EVIDENCE OF SMOKE/FIRE/DAMAGE. WE TAXIED TO OUR GATE WHERE WE MET THE ZZZ CFR CHIEF. HE VERIFIED THERE WAS NO ABNORMAL INDICATIONS IN THE AVIONICS BAY OR THE AFT EQUIP BAY. THE PAX WERE TOLD THERE WAS AN ELECTRICAL PROB AND WE NEEDED TO LAND. WE THEN DEPLANED THE PAX. CONTRACT MAINT ARRIVED. AFTER THEY INSPECTED THE L FORWARD PORTION OF THE AVIONICS BAY; HE INDICATED WE HAD MELTED WIRES AND AN ELECTRICAL FIRE AT SOME POINT. HAVING SEEN THE DAMAGE; IT WAS APPARENT THAT WE SHOULD HAVE COMPLETED THE QRH PROC FOR SMOKE OR ELECTRICAL FIRE. HOWEVER; THERE WAS SOME SATISFACTION TO US THAT THE PROB HAD FIXED ITSELF BY ISOLATING THAT AC BUS AND STOPPING SHORT. WE WERE UNDER THE IMPRESSION THERE WAS AN ELECTRICAL FAILURE; NOT A FIRE. WE STRONGLY BELIEVE THE PROB OCCURRED (AFTER REVIEWING ALL THE EVENTS) BECAUSE OF WATER ON THE COCKPIT AND GALLEY FLOOR. THERE WAS HEAVY SNOW FALLING AT THE GATE IN ZZZ1 AND THE SNOW PROBABLY MELTED AND LEAKED DOWN TO THE ELECTRICAL EQUIP. THIS COULD BE PREVENTED BY HAVING A CANOPY COVERING THE DOORWAY WITH JETWAY OR SOMETHING TO KEEP RAIN/SNOW OUTSIDE THE AIRPLANE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ENTIRE #1 AC BUS FAILED AND THE #1 XFER BUS FAILED. THE RPTR INDICATED THAT FROM THEN ON; ALL KINDS OF FAILURES AND FAIL MESSAGES WERE DISPLAYED. THE RPTR STATED THE QRH CHKS WERE RUN THROUGH FOR SYSTEMS THAT FAILED BUT WAS UNAWARE THAT A FIRE WAS PRESENT AS NO SMOKE WAS DETECTED VISUALLY. RPTEDLY; THE FO DID SMELL ELECTRICAL HEAT ODOR BUT NOT IN AMOUNTS THAT WOULD INDICATE A FIRE. THE RPTR STATED THE SIT HAS HAPPENED BEFORE WHERE SNOW OR RAIN DRAIN INTO THE ELECTRICAL AND ELECTRONICS BAY AND CAUSED PROBS WITH THE SYSTEMS; ADDING AN EFFECTIVE WATER BARRIER OR DRIP SHIELD NEEDS TO BE IN PLACE TO PROTECT THE ELECTRONICS BAY. SUPPLEMENTAL INFO FROM ACN 680209: AT FL230; ALL CRTS WENT OUT MOMENTARILY; FOLLOWED IMMEDIATELY BY ELECTRICAL BURNING SMELL. MECH SAID THERE WAS EVIDENCE OF A FIRE IN THE AVIONICS BAY. HOWEVER; DUE TO THE DISSIPATION OF THE SMELL IN FLT; WE HAD NO REASON TO BELIEVE THERE WAS AN ACTUAL FIRE UNTIL WE WERE ABLE TO LOOK IN THE AVIONICS BAY.

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.