B747-200 FLC RETURNS TO MANILA AFTER TKOF WHEN THE SO NOTES THAT ALL BUT THE AFT #2 TANK BOOST PUMP WARNING LIGHTS WERE ON. ALL SWITCHES WERE 'ON' AND THERE WAS A FUEL IMBALANCE IN TANK #2 INDICATING THAT TANK #2 WAS FEEDING ALL ENGS. THE POSTFLT INSPECTION LATER REVEALED THAT THOSE RESPECTIVE CIRCUIT BREAKERS HAD BEEN PULLED IN A PREVIOUS MAINT SPONSORED GND TEST. THE RPTR'S TEXT IS NOT CLR AS TO WHETHER THEY HAD BEEN PLACED BACK IN OP PRIOR TO THIS FLT. NOT NOTED IN THE LOGBOOK.

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TKOF AND INITIAL CLB WERE NORMAL WITH FULL 'J' PWR. WHILE REVIEWING THE CLB CHKLIST OUT OF 10000 FT; THE SO NOTICED 7 OF 8 LOW PRESSURE LIGHTS ILLUMINATED ON THE FUEL PANEL. ONLY THE #2 AFT PRESSURE LIGHT WAS EXTINGUISHED. THERE WAS A SLIGHT IMBALANCE BTWN #2 AND #3 TANKS. AT THIS POINT; ACCORDING TO THE PANEL INDICATIONS; #2 AFT WAS THE ONLY BOOST PUMP WORKING. ALL OF THE XFEEDS WERE OPEN. PER THE FUEL BURN SEQUENCE; #2 AND #3 TANKS WERE TO FEED ALL ENGS FOR A SHORT PERIOD ON CLBOUT. SINCE WE WERE CLRED TO FL410 AND CLBING QUITE RAPIDLY (DUE TO THE ACFT'S LIGHT WEIGHT); I SUGGESTED A LOWER ALT FOR LEVELOFF TO ENSURE ADEQUATE FUEL PRESSURE AND TO TROUBLESHOOT THE MALFUNCTION. HOWEVER; THE CAPT ELECTED TO CONTINUE THE CLB FOR THE TIME BEING AND GAVE ME THE FLT CTLS SO HE COULD WORK WITH THE SO. CIRCUIT BREAKERS WERE CHKED AND THE COCKPIT OPERATING MANUAL REVIEWED. BY THIS TIME; IT WAS EVIDENT THAT THE #2 TANK WAS FEEDING ALL ENGS. (#2 WAS SHOWING A 3000 TO 4000 LB IMBALANCE.) THE CAPT ELECTED TO IMMEDIATELY RETURN TO THE DEP ARPT. HE REQUESTED PRIORITY HANDLING. AFTER PARKING AT THE GATE; MAINT PERSONNEL ENTERED THE ACFT AND INDICATED THE BOOST PUMP CIRCUIT BREAKERS HAD BEEN PULLED ON THE GND FOR A SPECIAL CHK AND THERE WAS NO 'RECORD' OF THEM BEING RESET. I FOUND THIS QUITE INTERESTING AS THERE WAS NO RECORD OF THE CHK IN THE LOGBOOK ONBOARD THE ACFT. THERE WAS AN INFERENCE BY GND PERSONNEL THAT WE COULD HAVE RETURNED FOR ANOTHER REASON. THIS DID NOT SET WELL WITH ANY OF THE FLC MEMBERS. THE CAPT CALLED OUR CHIEF PLT; CHIEF OF TRAINING AND MAINT CTL TO DISCUSS THE SIT. APPARENTLY; HE WAS TOLD THAT NO OTHER CHKS WERE FEASIBLE OTHER THAN RESETTING THE CIRCUIT BREAKERS AND ENSURING THE PUMPS WERE PUTTING OUT PRESSURE. THE CHIEF PLT AND CHIEF OF TRAINING WERE COMFORTABLE WITH OUR CREW CONTINUING ON TO OUR ORIGINAL DEST. MAINT COMPLETED THE CHKS AND WE DEPARTED AND LANDED AT OUR ORIGINAL DEST WITHOUT INCIDENT. I THOUGHT WE HANDLED THE INFLT MALFUNCTION FAIRLY WELL. THE CAPT SOLICITED INPUTS AND MADE THE FINAL DECISIONS. HE DELEGATED ACFT CTL IN ORDER TO MANAGE THE SIT FIRST HAND. HUMAN ERROR: I FIND IT VERY HARD TO BELIEVE THE SO MISSED LOW PRESSURE LIGHTS ON 2 CHKLISTS AND 3 TO 4 FLOW PATTERNS PRIOR TO THE TKOF. UNDER THAT SCENARIO; THE #2 AFT LIGHT WAS OBVIOUSLY EXTINGUISHED AND WOULD HAVE PRESENTED AN UNBALANCED LIGHT PATTERN; MAKING IT EVEN MORE NOTICEABLE. THE SO IS KNOWN FOR BEING QUITE METICULOUS. LOGBOOKS: I'M ASSUMING THE BOOST PUMP CHK WAS ENTERED INTO THE COMPUTER BASED LOGBOOK. NON ROUTINE MAINT SHOULD BE ENTERED INTO THE ACFT ONBOARD LOGBOOK. THIS WOULD ALERT THE FLC OF POSSIBLE ABNORMALITIES. SUPPLEMENTAL INFO FROM ACN 387560: AFTER CONDUCTING A NORMAL INTERIOR PREFLT; I PROCEEDED TO DO THE EXTERIOR PREFLT AND HEARD THE APU SHUT DOWN. MAINT RESTARTED THE APU AND THE INS'S WERE REALIGNED; #4 ENG WAS STARTED AT THE GATE. ALL PROCS AND CHKLISTS WERE COMPLETED PRIOR TO TKOF. FULL 75% PWR WAS USED FOR TKOF. THE TKOF AND CLB WERE UNEVENTFUL. AT APPROX 10000 FT I DID MY CLB CHK AND NOTICED SEVERAL BOOST PUMP LOW PRESSURE LIGHTS ILLUMINATED. ALL COCKPIT CIRCUIT BREAKERS WERE CHKED AND FOUND TO BE NORMAL. ALL ENGS WERE OPERATING NORMAL. CALLBACK CONVERSATION WITH RPTR OF ACN 387560 REVEALED THE FOLLOWING INFO: THIS RPTR WAS THE SO. WITH REF TO THE APU SHUTTING DOWN DURING HIS PREFLT; HE SAID THAT HE WAS LATER TOLD BY MAINT THAT THERE HAD BEEN A PROB WITH A SWITCH; IT HAVING TRIPPED THEREBY SHUTTING DOWN THE APU. THE MAINT MAN THOUGHT IT WAS A 'RESET SWITCH.' MAINT ALSO SAID THAT THERE WAS A PROB WITH A FAULTY BATTERY CHARGER. SINCE THEY DID NOT WANT ANY ELECTRICAL PROBS LATER; THE #4 ENG WAS STARTED AT THE GATE; THE ACFT PUSHED BACK AND THE REMAINING ENGS STARTED. THE APU WAS THEN SHUT DOWN. RPTR SAID THAT THE CAPT NORMALLY LOOKS AT THE SO'S PANEL FOR ANY LIGHTS; AS THE PANEL SHOULD BE UNLIT; WITH NO FUEL BOOST PUMP LIGHTS ON. IN THIS EVENT; THE CAPT LATER SAID THAT HE HAD FAILED TO DO THIS VISUAL SCAN AS THERE HAD BEEN CONSTRUCTION ON THE ARPT AND HE WAS TOO PREOCCUPIED IN TAXIING TO TURN AND CHK FOR THESE LIGHTS. THROUGH 3000 FT WITH THE FLAPS RETRACTED; THE SO WENT THROUGH HIS XFEED SET UP; INSURING XFEEDS OPEN; SHUTTING OFF MAIN TANK BOOST PUMPS #1 AND #4 TO FEED OUT OF TANKS #2 AND #3 TO ALL ENGS. HE HAD NOT; UP TO THIS POINT; NOTICED ANYTHING UNUSUAL. HE SAID THAT THE PANEL LIGHT SELECTOR SWITCH WAS IN THE 'BRIGHT' POS. THE ONLY CHANGE OR DIFFERENCE WITH THIS ACFT WAS THAT THE FUEL GAUGES WERE OF A NEWER TYPE; A DIGITAL RATHER THAN THE OLD 'ANALOG' TYPE. THE DIGITS WITHIN THESE GAUGES ARE AMBER COLORED; THE SAME COLOR AS THE BOOST PUMP LOW PRESSURE WARNING LIGHTS; AND WOULD PUT OUT A CERTAIN LEVEL OF LIGHT FROM THE PANEL. IT IS A 'DIFFERENT LOOK THAN IT USED TO BE.' AT HIS 10000 FT CLB CHK HE COMPLETED HIS CHKLISTS AND UPON TURNING BACK TO THE PANEL SAW ALL THESE BRIGHT WARNING LIGHTS ON; EXCEPT #2 AFT. HE SAYS HE COULD HAVE MISSED THEM BUT DOESN'T KNOW HOW. UPON RETURN TO THE GATE THE MAINT MAN MENTIONED THAT HE THOUGHT THAT THE LOWER 41 CIRCUIT BREAKERS WERE STILL OUT EXCEPT FOR THE #2 AFT BREAKER WHICH HAD POWERED THE PUMP FOR THE APU. IT WAS EXPLAINED THAT MAINT HAS A NEW PROC THAT THEY DO BEFORE DEP; HE THOUGHT IT WAS CHKING FOR RESISTANCE LEVELS IN THE BOOST PUMP CIRCUITS OR WIRING. THIS WAS A PROC HE HAD NOT HEARD OF BEFORE. WHEN ASKED DURING CALLBACK; HE DIDN'T KNOW IF PULLING THE LOWER 41 BREAKERS WOULD DEACTIVATE THE BOOST PUMP WARNING LIGHTS IN THE COCKPIT BUT DIDN'T THINK SO. HE SAYS THAT THE FAA KNOWS OF THIS INCIDENT; MOST LIKELY THROUGH A COMPANY SELF DISCLOSURE PROC.