Narrative:

Approximately 44000 pounds of fuel was dumped. The fuel dump was at FL340 between the diversion point and the top of descent point. The landing was below the aircraft maximum landing weight at approximately 456000 pounds gross weight. The diversion to the nearest suitable airport was initiated as a consequence of an array of status indications. At approximately 1.5 hours after takeoff; four status msgs appeared within a period of several mins. These were; 'brake temperature system;' 'main gear steering;' 'bleed hpsov left;' and 'pack right.' the information was passed to maintenance control and dispatch; and the flight was continued with this condition stable. The condition began to deteriorate; however; approximately 1/2 to 3/4 hour prior to the diversion point. Multiple additional status msgs appeared as the flight progressed. At the time of the diversion decision; the list had increased to 13 msgs. Satcom conferencing was initiated with maintenance control and dispatch. Despite quite direct inquiry; maintenance control was unable to provide any technical information or assistance to the flight crew. Consequently; the flight crew was unable to assure the safe continuation of the flight and a landing was required. Dispatch concurred. In terminating the flight; an important consideration was the fact that three of the status msgs indicated various elms system failures. The elms system has a known history of overheating and fire events. Recently; procedures for the use of ground power of the B777 have been changed in order to prevent incurring damage to the elms system. In actual fact; however; it is frequently observed that company use of ground power on the B777 is not in compliance with the changed procedure. As a consequence of this; flight crews recognize the gravity of elms related anomalies.callback conversation with reporter revealed the following information: reporter stated his carrier has recently made procedure changes for the use of ground power on the B777 in order to prevent incurring damage to the elms system. Their operations manual now says to use two ground power cords when supplying electrical ground power to the aircraft; or one ground cord and leave APU running. Reporter stated this was a boeing recommendation; perhaps as a result of boeing's investigation of several in-service reports of power panel overheat events. This was being done to reduce or eliminate the heat build-up in the P-200 and P-300 elms power panel contactors; which includes the right bus tie breaker (rbtb); the auxiliary power breaker (apb) and the primary external power contactor (pepc). Reporter stated that the new company procedures in the operations manual for supplying ground power are not being followed by ramp personnel. Reporter stated that his company has just made a minor change to this two electrical cord requirement that now states; 'this is a recommendation; not a requirement.' reporter feels his company is not addressing the serious potential for an in-flight fire in the lower main equipment center (mec); especially over water.

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Original NASA ASRS Text

Title: A B777-200 PLT DESCRIBES HOW MULTIPLE STATUS MESSAGES DISPLAYED WITHIN SEVERAL MINUTES; REQUIRED A DIVERSION LNDG. THREE OF THE STATUS MESSAGES INDICATED VARIOUS ELMS SYSTEM FAILURES.

Narrative: APPROX 44000 LBS OF FUEL WAS DUMPED. THE FUEL DUMP WAS AT FL340 BETWEEN THE DIVERSION POINT AND THE TOP OF DSCNT POINT. THE LNDG WAS BELOW THE ACFT MAX LNDG WT AT APPROX 456000 LBS GROSS WT. THE DIVERSION TO THE NEAREST SUITABLE ARPT WAS INITIATED AS A CONSEQUENCE OF AN ARRAY OF STATUS INDICATIONS. AT APPROX 1.5 HRS AFTER TAKEOFF; FOUR STATUS MSGS APPEARED WITHIN A PERIOD OF SEVERAL MINS. THESE WERE; 'BRAKE TEMP SYS;' 'MAIN GEAR STEERING;' 'BLEED HPSOV L;' AND 'PACK R.' THE INFO WAS PASSED TO MAINT CTL AND DISPATCH; AND THE FLT WAS CONTINUED WITH THIS CONDITION STABLE. THE CONDITION BEGAN TO DETERIORATE; HOWEVER; APPROX 1/2 TO 3/4 HOUR PRIOR TO THE DIVERSION POINT. MULTIPLE ADDITIONAL STATUS MSGS APPEARED AS THE FLT PROGRESSED. AT THE TIME OF THE DIVERSION DECISION; THE LIST HAD INCREASED TO 13 MSGS. SATCOM CONFERENCING WAS INITIATED WITH MAINT CTL AND DISPATCH. DESPITE QUITE DIRECT INQUIRY; MAINT CTL WAS UNABLE TO PROVIDE ANY TECHNICAL INFORMATION OR ASSISTANCE TO THE FLT CREW. CONSEQUENTLY; THE FLT CREW WAS UNABLE TO ASSURE THE SAFE CONTINUATION OF THE FLT AND A LNDG WAS REQUIRED. DISPATCH CONCURRED. IN TERMINATING THE FLT; AN IMPORTANT CONSIDERATION WAS THE FACT THAT THREE OF THE STATUS MSGS INDICATED VARIOUS ELMS SYSTEM FAILURES. THE ELMS SYSTEM HAS A KNOWN HISTORY OF OVERHEATING AND FIRE EVENTS. RECENTLY; PROCS FOR THE USE OF GND POWER OF THE B777 HAVE BEEN CHANGED IN ORDER TO PREVENT INCURRING DAMAGE TO THE ELMS SYSTEM. IN ACTUAL FACT; HOWEVER; IT IS FREQUENTLY OBSERVED THAT COMPANY USE OF GND POWER ON THE B777 IS NOT IN COMPLIANCE WITH THE CHANGED PROC. AS A CONSEQUENCE OF THIS; FLT CREWS RECOGNIZE THE GRAVITY OF ELMS RELATED ANOMALIES.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED HIS CARRIER HAS RECENTLY MADE PROC CHANGES FOR THE USE OF GND POWER ON THE B777 IN ORDER TO PREVENT INCURRING DAMAGE TO THE ELMS SYSTEM. THEIR OPERATIONS MANUAL NOW SAYS TO USE TWO GND POWER CORDS WHEN SUPPLYING ELECTRICAL GND POWER TO THE ACFT; OR ONE GND CORD AND LEAVE APU RUNNING. RPTR STATED THIS WAS A BOEING RECOMMENDATION; PERHAPS AS A RESULT OF BOEING'S INVESTIGATION OF SEVERAL IN-SERVICE RPTS OF POWER PANEL OVERHEAT EVENTS. THIS WAS BEING DONE TO REDUCE OR ELIMINATE THE HEAT BUILD-UP IN THE P-200 AND P-300 ELMS POWER PANEL CONTACTORS; WHICH INCLUDES THE RIGHT BUS TIE BREAKER (RBTB); THE AUXILIARY POWER BREAKER (APB) AND THE PRIMARY EXTERNAL POWER CONTACTOR (PEPC). RPTR STATED THAT THE NEW COMPANY PROCS IN THE OPERATIONS MANUAL FOR SUPPLYING GND POWER ARE NOT BEING FOLLOWED BY RAMP PERSONNEL. RPTR STATED THAT HIS COMPANY HAS JUST MADE A MINOR CHANGE TO THIS TWO ELECTRICAL CORD REQUIREMENT THAT NOW STATES; 'THIS IS A RECOMMENDATION; NOT A REQUIREMENT.' RPTR FEELS HIS COMPANY IS NOT ADDRESSING THE SERIOUS POTENTIAL FOR AN IN-FLIGHT FIRE IN THE LOWER MAIN EQUIPMENT CENTER (MEC); ESPECIALLY OVER WATER.

Data retrieved from NASA's ASRS site as of May 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.