Narrative:

We had departed ord for sfo at very near maximum allowable gross weight (structural, runway and performance) limit. Initial climb out was uneventful. As we climbed through about FL210 the captain (PF) noticed a mild but obvious yawing oscillation. The yaw dampers didn't show any unusual indications and we continued climb. A few mins later, climbing through approximately FL270 we experienced a major electrical malfunction which initially appeared to be a loss of all generators. The captain selected emergency power on and ignition. Overhead and air start (immediate action items for the 'loss of all generators' procedure). The #2 engine flamed out (probably due to lack of fuel pump pressure). The captain (PF) continued flying using standby attitude indicator and altimeters. I was unable to transmit or receive because of the electrical failure. So the captain requested a lower altitude and (after quickly conferring) return to ord. He had to perform a timed compass turn because the #1 INS (heading and attitude reference) had failed. As the flight engineer and I worked through the 'loss of all generators' procedure, we discovered and informed the captain that the #1 generator was still on- line, but that we had some unexplained failures on that bus (such as the #1 INS). Once power was restored to the right emergency AC/dc busses (my instruments) by deploying the air driven generator (part of the procedure), I assumed the duties of PF. The flight engineer (now working with the captain) was unable to reset #2 generator or #3 generator. ZAU cleared us to intercept the runway 9R localizer and for the approach about 80 mi out -- very accommodating. The flight engineer attempted to start the APU for electrical power but the starter would not engage. #2 engine restarted descending through about 24500 ft. We were unable to dump fuel because we had no electrical power on that bus. We were concerned about our stopping capabilities and structural landing limit weight (363500 pounds). The flight engineer tried starting the APU again at about 12000 ft MSL, this time successfully. The APU pwred the #2 and #3 busses. We dumped fuel on approach, approximately 20000 pounds, to a landing weight of 369000 pounds. Fuel dump was discontinued at about 1000 ft AGL. The approach was in VMC. The captain flew from 500 ft AGL to landing. The landing was uneventful, with all 'stopping' equipment operating normally (reversers, anti-skid, etc). Callback conversation with reporter revealed the following information: the first officer says that the #1 INS failure problem is still unresolved. This system is supposed to operate if its respective generator bus is pwred. The first indication of problems with any of the aircraft system was the electrical system going off the line. Callback conversation with reporter acn #303754 revealed the following information: the captain says that the first indication of problems with the aircraft system was the yaw damper circuit breaker opening. As the flight crew was preparing to reset the circuit breaker the #2 and #3 generators disconnected. Later, maintenance discovered that the #3 constant speed drive had disintegrated. Also, the bus tie from the #1 generator and its load-shedding function did not operate as designed. The APU simply would not start until the aircraft was around 10000-12000 ft and have not been told what maintenance discovered there. The #2 engine loss is normal at altitude when the electrical pumps fail. The reporter has had several conferences with the company and they are attempting to discover the causes of these multiple problems.

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Original NASA ASRS Text

Title: MULTIPLE ELECTRICAL FAILURE. ENG FLAMEOUT.

Narrative: WE HAD DEPARTED ORD FOR SFO AT VERY NEAR MAX ALLOWABLE GROSS WT (STRUCTURAL, RWY AND PERFORMANCE) LIMIT. INITIAL CLBOUT WAS UNEVENTFUL. AS WE CLBED THROUGH ABOUT FL210 THE CAPT (PF) NOTICED A MILD BUT OBVIOUS YAWING OSCILLATION. THE YAW DAMPERS DIDN'T SHOW ANY UNUSUAL INDICATIONS AND WE CONTINUED CLB. A FEW MINS LATER, CLBING THROUGH APPROX FL270 WE EXPERIENCED A MAJOR ELECTRICAL MALFUNCTION WHICH INITIALLY APPEARED TO BE A LOSS OF ALL GENERATORS. THE CAPT SELECTED EMER PWR ON AND IGNITION. OVERHEAD AND AIR START (IMMEDIATE ACTION ITEMS FOR THE 'LOSS OF ALL GENERATORS' PROC). THE #2 ENG FLAMED OUT (PROBABLY DUE TO LACK OF FUEL PUMP PRESSURE). THE CAPT (PF) CONTINUED FLYING USING STANDBY ATTITUDE INDICATOR AND ALTIMETERS. I WAS UNABLE TO XMIT OR RECEIVE BECAUSE OF THE ELECTRICAL FAILURE. SO THE CAPT REQUESTED A LOWER ALT AND (AFTER QUICKLY CONFERRING) RETURN TO ORD. HE HAD TO PERFORM A TIMED COMPASS TURN BECAUSE THE #1 INS (HDG AND ATTITUDE REF) HAD FAILED. AS THE FE AND I WORKED THROUGH THE 'LOSS OF ALL GENERATORS' PROC, WE DISCOVERED AND INFORMED THE CAPT THAT THE #1 GENERATOR WAS STILL ON- LINE, BUT THAT WE HAD SOME UNEXPLAINED FAILURES ON THAT BUS (SUCH AS THE #1 INS). ONCE PWR WAS RESTORED TO THE R EMER AC/DC BUSSES (MY INSTS) BY DEPLOYING THE ADG (PART OF THE PROC), I ASSUMED THE DUTIES OF PF. THE FE (NOW WORKING WITH THE CAPT) WAS UNABLE TO RESET #2 GENERATOR OR #3 GENERATOR. ZAU CLRED US TO INTERCEPT THE RWY 9R LOC AND FOR THE APCH ABOUT 80 MI OUT -- VERY ACCOMMODATING. THE FE ATTEMPTED TO START THE APU FOR ELECTRICAL PWR BUT THE STARTER WOULD NOT ENGAGE. #2 ENG RESTARTED DSNDING THROUGH ABOUT 24500 FT. WE WERE UNABLE TO DUMP FUEL BECAUSE WE HAD NO ELECTRICAL PWR ON THAT BUS. WE WERE CONCERNED ABOUT OUR STOPPING CAPABILITIES AND STRUCTURAL LNDG LIMIT WT (363500 LBS). THE FE TRIED STARTING THE APU AGAIN AT ABOUT 12000 FT MSL, THIS TIME SUCCESSFULLY. THE APU PWRED THE #2 AND #3 BUSSES. WE DUMPED FUEL ON APCH, APPROX 20000 LBS, TO A LNDG WT OF 369000 LBS. FUEL DUMP WAS DISCONTINUED AT ABOUT 1000 FT AGL. THE APCH WAS IN VMC. THE CAPT FLEW FROM 500 FT AGL TO LNDG. THE LNDG WAS UNEVENTFUL, WITH ALL 'STOPPING' EQUIP OPERATING NORMALLY (REVERSERS, ANTI-SKID, ETC). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE FO SAYS THAT THE #1 INS FAILURE PROB IS STILL UNRESOLVED. THIS SYS IS SUPPOSED TO OPERATE IF ITS RESPECTIVE GENERATOR BUS IS PWRED. THE FIRST INDICATION OF PROBS WITH ANY OF THE ACFT SYS WAS THE ELECTRICAL SYS GOING OFF THE LINE. CALLBACK CONVERSATION WITH RPTR ACN #303754 REVEALED THE FOLLOWING INFO: THE CAPT SAYS THAT THE FIRST INDICATION OF PROBS WITH THE ACFT SYS WAS THE YAW DAMPER CIRCUIT BREAKER OPENING. AS THE FLC WAS PREPARING TO RESET THE CIRCUIT BREAKER THE #2 AND #3 GENERATORS DISCONNECTED. LATER, MAINT DISCOVERED THAT THE #3 CONSTANT SPD DRIVE HAD DISINTEGRATED. ALSO, THE BUS TIE FROM THE #1 GENERATOR AND ITS LOAD-SHEDDING FUNCTION DID NOT OPERATE AS DESIGNED. THE APU SIMPLY WOULD NOT START UNTIL THE ACFT WAS AROUND 10000-12000 FT AND HAVE NOT BEEN TOLD WHAT MAINT DISCOVERED THERE. THE #2 ENG LOSS IS NORMAL AT ALT WHEN THE ELECTRICAL PUMPS FAIL. THE RPTR HAS HAD SEVERAL CONFERENCES WITH THE COMPANY AND THEY ARE ATTEMPTING TO DISCOVER THE CAUSES OF THESE MULTIPLE PROBS.

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.