Narrative:

At FL300 en route from ZZZZ1-ZZZ; we received a level 1 'battery discharging' alert. The alert stayed on for approximately 15-30 seconds and then went out. It would then cycle back on after about 1 or 2 mins. It repeated this cycle for the rest of the flight. The volts for the battery on the electrical page cycled from 30 volts to 33 volts. The alert would come on when the voltage would reach 32-33 volts and would extinguish when the volts reached 30 volts. During the entire flight the battery voltage never dropped below 30 volts. All other electrical system were normal. We consulted with operations maintenance; the technical representatives; the duty officer; and standards via a satcom call. After verifying with maintenance and the technical representative that the battery was not draining and that there seemed to be no serious problem at hand I decided to continue on to ZZZZ2 and monitor the situation. All parties that were in on the conference call concurred with my decision. I had operations give possible divert fields both ahead and behind us a heads up that we might need to do an emergency divert; if the situation got any worse. About 5 mins after concluding the satcom call we received a level 2 'FCC 1A data fault' alert; with a level 1 'sel yaw switch B off' and a 'sel lsas lib off' alerts. The captain's flight director; airspeed ball and foot; and autoplt #1 were lost. We ran the QRH and decided to commence an airborne divert. After coordinating the rerte with radio; we initiated another satcom call with all of the same parties; to advise them that we were turning back to ZZZZ as we had previously discussed. During the previous discussion; ZZZZ was the unanimous choice for a divert if we needed to divert; without the battery discharging prior to the half way point. Since that was still the case we declared an emergency and started back to ZZZZ. En route to ZZZZ operations reran our fuel numbers and it showed that we would need to dump some fuel to get down to our maximum landing weight of 481.5. A total of 13000 pounds were dumped at FL300. That gave us a landing weight of 479.5. The rest of the flight and the landing were uneventful.

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Original NASA ASRS Text

Title: AN MD-11 FLT CREW ON A TRANSOCEANIC ROUTE RECEIVED MULTIPLE ELEC COMPONENT FAULT MESSAGES. THEY DECLARED AN EMERGENCY AND DIVERTED.

Narrative: AT FL300 ENRTE FROM ZZZZ1-ZZZ; WE RECEIVED A LEVEL 1 'BATTERY DISCHARGING' ALERT. THE ALERT STAYED ON FOR APPROX 15-30 SECONDS AND THEN WENT OUT. IT WOULD THEN CYCLE BACK ON AFTER ABOUT 1 OR 2 MINS. IT REPEATED THIS CYCLE FOR THE REST OF THE FLT. THE VOLTS FOR THE BATTERY ON THE ELECTRICAL PAGE CYCLED FROM 30 VOLTS TO 33 VOLTS. THE ALERT WOULD COME ON WHEN THE VOLTAGE WOULD REACH 32-33 VOLTS AND WOULD EXTINGUISH WHEN THE VOLTS REACHED 30 VOLTS. DURING THE ENTIRE FLT THE BATTERY VOLTAGE NEVER DROPPED BELOW 30 VOLTS. ALL OTHER ELECTRICAL SYS WERE NORMAL. WE CONSULTED WITH OPS MAINT; THE TECHNICAL REPRESENTATIVES; THE DUTY OFFICER; AND STANDARDS VIA A SATCOM CALL. AFTER VERIFYING WITH MAINT AND THE TECHNICAL REPRESENTATIVE THAT THE BATTERY WAS NOT DRAINING AND THAT THERE SEEMED TO BE NO SERIOUS PROB AT HAND I DECIDED TO CONTINUE ON TO ZZZZ2 AND MONITOR THE SITUATION. ALL PARTIES THAT WERE IN ON THE CONFERENCE CALL CONCURRED WITH MY DECISION. I HAD OPS GIVE POSSIBLE DIVERT FIELDS BOTH AHEAD AND BEHIND US A HEADS UP THAT WE MIGHT NEED TO DO AN EMER DIVERT; IF THE SITUATION GOT ANY WORSE. ABOUT 5 MINS AFTER CONCLUDING THE SATCOM CALL WE RECEIVED A LEVEL 2 'FCC 1A DATA FAULT' ALERT; WITH A LEVEL 1 'SEL YAW SWITCH B OFF' AND A 'SEL LSAS LIB OFF' ALERTS. THE CAPT'S FLT DIRECTOR; AIRSPD BALL AND FOOT; AND AUTOPLT #1 WERE LOST. WE RAN THE QRH AND DECIDED TO COMMENCE AN AIRBORNE DIVERT. AFTER COORDINATING THE RERTE WITH RADIO; WE INITIATED ANOTHER SATCOM CALL WITH ALL OF THE SAME PARTIES; TO ADVISE THEM THAT WE WERE TURNING BACK TO ZZZZ AS WE HAD PREVIOUSLY DISCUSSED. DURING THE PREVIOUS DISCUSSION; ZZZZ WAS THE UNANIMOUS CHOICE FOR A DIVERT IF WE NEEDED TO DIVERT; WITHOUT THE BATTERY DISCHARGING PRIOR TO THE HALF WAY POINT. SINCE THAT WAS STILL THE CASE WE DECLARED AN EMER AND STARTED BACK TO ZZZZ. ENRTE TO ZZZZ OPS RERAN OUR FUEL NUMBERS AND IT SHOWED THAT WE WOULD NEED TO DUMP SOME FUEL TO GET DOWN TO OUR MAX LNDG WT OF 481.5. A TOTAL OF 13000 LBS WERE DUMPED AT FL300. THAT GAVE US A LNDG WT OF 479.5. THE REST OF THE FLT AND THE LNDG WERE UNEVENTFUL.

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.