Narrative:

Preflight planning for flight was remarkable until reading the maintenance section. Aircraft had arrived with an unresolved equipment cooling system malfunction. An initial review of the log history revealed that this problem had been deferred for 5 days. The placard called for both packs to be operated it outside temperatures exceeded 29 degrees C. According to muc ATIS; outside air temperature at that time was only 28 degrees C. Nevertheless; we had the APU and both packs running anyway. We turned on the IRS units; within 2 or 3 mins the wheel well horn went off; and the equipment cooling overheat light illuminated. We notified the station and called for maintenance. Troubleshooting with muc ground maintenance proved fruitless. No combination of switch position would extinguish the overheat light. A more thorough review of the aircraft log by dispatch revealed that this problem had in fact been chronic. Further; it appeared that a dedicated attempt to troubleshoot and correct this malfunction in los angeles had been aborted; for reasons unknown to us. Instead of being fixed there and then; the problem was deferred once again. This time; however; there was no quick fix to extinguish the overheat light. Only after this IRS panel was completely turned off did the warning horn go out and the overheat light go off. At this point; the station manager became a factor. He objected to captain's decision and openly questioned his judgement. He argued that the malfunctioning equipment cooling system had a 'legal deferral' and that the inbound pilot had flown it in with no problem (clearly this was wrong; the overheat light was steady on). Subsequent to this; the station manager went around behind the captain's back; trying to persuade other crew members (including first officer's and some of the flight attendants) to challenge the captain's decision. Both first officer's and I informed the station manager that just because the inbound crew had elected to fly with the deferral didn't mean that it was necessarily either legal or wise. We also attempted to persuade him that even if the aircraft had no mechanical problem flying in; it had one now; and that was the driving factor. He didn't seem to grasp the flight safety ramifications of this malfunction; even after first officer and I recalled for him an md-11 crash from a similar equipment cooling failure and fire. The station manager seems to be a sincere; reasonable; and hard-working employee; but he would not be persuaded that this was not some deliberate act by captain. Overall observations: 1) this flight was canceled for one and only one reason: inadequate maintenance to correct a serious system malfunction. An aggravating factor was maintenance's willingness to keep deferring this problem; especially on an aircraft dispatched to an international non-maintenance station involving extended overwater flight. 2) the flight safety implications of this incident are tremendous.

Related reports:

Google
 

Original NASA ASRS Text

Title: A B767-300 FLT CREW HAS CONCERN WITH MEL'ED EQUIP COOLING FAN INOP.

Narrative: PREFLT PLANNING FOR FLT WAS REMARKABLE UNTIL READING THE MAINT SECTION. ACFT HAD ARRIVED WITH AN UNRESOLVED EQUIP COOLING SYS MALFUNCTION. AN INITIAL REVIEW OF THE LOG HISTORY REVEALED THAT THIS PROB HAD BEEN DEFERRED FOR 5 DAYS. THE PLACARD CALLED FOR BOTH PACKS TO BE OPERATED IT OUTSIDE TEMPS EXCEEDED 29 DEGS C. ACCORDING TO MUC ATIS; OUTSIDE AIR TEMP AT THAT TIME WAS ONLY 28 DEGS C. NEVERTHELESS; WE HAD THE APU AND BOTH PACKS RUNNING ANYWAY. WE TURNED ON THE IRS UNITS; WITHIN 2 OR 3 MINS THE WHEEL WELL HORN WENT OFF; AND THE EQUIP COOLING OVERHEAT LIGHT ILLUMINATED. WE NOTIFIED THE STATION AND CALLED FOR MAINT. TROUBLESHOOTING WITH MUC GND MAINT PROVED FRUITLESS. NO COMBINATION OF SWITCH POS WOULD EXTINGUISH THE OVERHEAT LIGHT. A MORE THOROUGH REVIEW OF THE ACFT LOG BY DISPATCH REVEALED THAT THIS PROB HAD IN FACT BEEN CHRONIC. FURTHER; IT APPEARED THAT A DEDICATED ATTEMPT TO TROUBLESHOOT AND CORRECT THIS MALFUNCTION IN LOS ANGELES HAD BEEN ABORTED; FOR REASONS UNKNOWN TO US. INSTEAD OF BEING FIXED THERE AND THEN; THE PROB WAS DEFERRED ONCE AGAIN. THIS TIME; HOWEVER; THERE WAS NO QUICK FIX TO EXTINGUISH THE OVERHEAT LIGHT. ONLY AFTER THIS IRS PANEL WAS COMPLETELY TURNED OFF DID THE WARNING HORN GO OUT AND THE OVERHEAT LIGHT GO OFF. AT THIS POINT; THE STATION MGR BECAME A FACTOR. HE OBJECTED TO CAPT'S DECISION AND OPENLY QUESTIONED HIS JUDGEMENT. HE ARGUED THAT THE MALFUNCTIONING EQUIP COOLING SYS HAD A 'LEGAL DEFERRAL' AND THAT THE INBOUND PLT HAD FLOWN IT IN WITH NO PROB (CLRLY THIS WAS WRONG; THE OVERHEAT LIGHT WAS STEADY ON). SUBSEQUENT TO THIS; THE STATION MGR WENT AROUND BEHIND THE CAPT'S BACK; TRYING TO PERSUADE OTHER CREW MEMBERS (INCLUDING FO'S AND SOME OF THE FLT ATTENDANTS) TO CHALLENGE THE CAPT'S DECISION. BOTH FO'S AND I INFORMED THE STATION MGR THAT JUST BECAUSE THE INBOUND CREW HAD ELECTED TO FLY WITH THE DEFERRAL DIDN'T MEAN THAT IT WAS NECESSARILY EITHER LEGAL OR WISE. WE ALSO ATTEMPTED TO PERSUADE HIM THAT EVEN IF THE ACFT HAD NO MECHANICAL PROB FLYING IN; IT HAD ONE NOW; AND THAT WAS THE DRIVING FACTOR. HE DIDN'T SEEM TO GRASP THE FLT SAFETY RAMIFICATIONS OF THIS MALFUNCTION; EVEN AFTER FO AND I RECALLED FOR HIM AN MD-11 CRASH FROM A SIMILAR EQUIP COOLING FAILURE AND FIRE. THE STATION MGR SEEMS TO BE A SINCERE; REASONABLE; AND HARD-WORKING EMPLOYEE; BUT HE WOULD NOT BE PERSUADED THAT THIS WAS NOT SOME DELIBERATE ACT BY CAPT. OVERALL OBSERVATIONS: 1) THIS FLT WAS CANCELED FOR ONE AND ONLY ONE REASON: INADEQUATE MAINT TO CORRECT A SERIOUS SYS MALFUNCTION. AN AGGRAVATING FACTOR WAS MAINT'S WILLINGNESS TO KEEP DEFERRING THIS PROB; ESPECIALLY ON AN ACFT DISPATCHED TO AN INTL NON-MAINT STATION INVOLVING EXTENDED OVERWATER FLT. 2) THE FLT SAFETY IMPLICATIONS OF THIS INCIDENT ARE TREMENDOUS.

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.