Narrative:

Due to excess fuel burn on arrival narita, japan (minus 7000 pounds) was unable to hold 30 min as requested by ATC. Asked for and received priority handling for the approach. Callback conversation with reporter revealed the following information: the first officer reporter returned the call back. He stated that the reasons for the fuel burn being over the fuel burn figures in the computer flight plan were 4 fold. The first issue was that the flight, while under flight crew number 1 (captain and first officer) for 1/2 of the flight, had been held down, for a time, to FL230 that increased the fuel burn. While at a higher cruise level later, crew #1 encountered a second issue, mod turbulence, and climbed above optimum altitude for smoother air. Later in the flight that first crew was asked if they wished to maintain that altitude, which was by now below optimum altitude, for the remainder of the trip. They elected to ask for the higher flight level that flight planning showed to be more optimal, even though it was not correct for their weight at that point in time. (Reporter mentioned that this 'altitude slot' was a recurring problem over this route to nrt so crews sometimes do climb early) that was the third issue. The fourth issue that, overall, the winds aloft were averaging a 25 KT stronger head wind component as measured against the flight plan. Winds were simply stronger than expected. The captain and first officer (crew #2) had expected to arrive at nrt with about 31000 pounds of fuel. They were now short by 7000 pounds. The delay announced was for 30 min. The captain advised ATC that, 'we need to receive priority handling -- can't hold that long or we will have to divert.' ATC did not question this, they simply 'swapped' position of this flight with another company flight and the rptrs were then #1 for the release out of the holding pattern, which occurred within 1 min. Had the flight accepted the delay the flight would have then been planned to land with 18000 pounds of fuel, increasing the crew's concerns.

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Original NASA ASRS Text

Title: A B-747-400 CREW ISSUED A MINIMUM FUEL ADVISORY TO APCH CTLR IN FOREIGN AIRSPACE.

Narrative: DUE TO EXCESS FUEL BURN ON ARR NARITA, JAPAN (MINUS 7000 LBS) WAS UNABLE TO HOLD 30 MIN AS REQUESTED BY ATC. ASKED FOR AND RECEIVED PRIORITY HANDLING FOR THE APCH. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE FO RPTR RETURNED THE CALL BACK. HE STATED THAT THE REASONS FOR THE FUEL BURN BEING OVER THE FUEL BURN FIGURES IN THE COMPUTER FLT PLAN WERE 4 FOLD. THE FIRST ISSUE WAS THAT THE FLT, WHILE UNDER FLC NUMBER 1 (CAPT AND FO) FOR 1/2 OF THE FLT, HAD BEEN HELD DOWN, FOR A TIME, TO FL230 THAT INCREASED THE FUEL BURN. WHILE AT A HIGHER CRUISE LEVEL LATER, CREW #1 ENCOUNTERED A SECOND ISSUE, MOD TURB, AND CLBED ABOVE OPTIMUM ALT FOR SMOOTHER AIR. LATER IN THE FLT THAT FIRST CREW WAS ASKED IF THEY WISHED TO MAINTAIN THAT ALT, WHICH WAS BY NOW BELOW OPTIMUM ALT, FOR THE REMAINDER OF THE TRIP. THEY ELECTED TO ASK FOR THE HIGHER FLT LEVEL THAT FLT PLANNING SHOWED TO BE MORE OPTIMAL, EVEN THOUGH IT WAS NOT CORRECT FOR THEIR WT AT THAT POINT IN TIME. (RPTR MENTIONED THAT THIS 'ALT SLOT' WAS A RECURRING PROB OVER THIS RTE TO NRT SO CREWS SOMETIMES DO CLB EARLY) THAT WAS THE THIRD ISSUE. THE FOURTH ISSUE THAT, OVERALL, THE WINDS ALOFT WERE AVERAGING A 25 KT STRONGER HEAD WIND COMPONENT AS MEASURED AGAINST THE FLT PLAN. WINDS WERE SIMPLY STRONGER THAN EXPECTED. THE CAPT AND FO (CREW #2) HAD EXPECTED TO ARRIVE AT NRT WITH ABOUT 31000 LBS OF FUEL. THEY WERE NOW SHORT BY 7000 LBS. THE DELAY ANNOUNCED WAS FOR 30 MIN. THE CAPT ADVISED ATC THAT, 'WE NEED TO RECEIVE PRIORITY HANDLING -- CAN'T HOLD THAT LONG OR WE WILL HAVE TO DIVERT.' ATC DID NOT QUESTION THIS, THEY SIMPLY 'SWAPPED' POS OF THIS FLT WITH ANOTHER COMPANY FLT AND THE RPTRS WERE THEN #1 FOR THE RELEASE OUT OF THE HOLDING PATTERN, WHICH OCCURRED WITHIN 1 MIN. HAD THE FLT ACCEPTED THE DELAY THE FLT WOULD HAVE THEN BEEN PLANNED TO LAND WITH 18000 LBS OF FUEL, INCREASING THE CREW'S CONCERNS.

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.