Date: 201708
Flight conditions: VMC
Aircraft: Boeing Company Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Other All
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Troubleshooting; Confusion; Distraction
Anomaly: Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Human Factors; Company Policy; Weather
Primary problem: Company Policy

Narrative: Aircraft X was dispatched to ZZZ with a Planned Gate fuel of 183;385 pounds; with a projected landing fuel of 14;061 pounds. Aside from planned burn; additional fuel was included for FAR's; weather deviations; taxi and contingency. The crew was in agreement with Dispatch that the fuel load was appropriate for the flight. Dispatcher remarks included that our crossing time at ZZZZZ Intersection (arrival fix into ZZZ); should be no earlier than XA18. Total SOB was 215; which included the crew and passengers. Payload was primarily the gear and equipment.  We departed approximately 30 minutes after an on-time pushback. After Takeoff the First Officer (FO); who was Pilot Flying (PF); remarked that the airplane seemed heavier than normal during the take-off. During the climbout; we set the PERF INDEX to 5; in anticipation of being very early at the ZZZZZ Intersection fix; an action which would normally contribute to a lower fuel burn than planned. The flight was normal but a trend started developing that fuel burn was higher than planned. For the most part; we crossed the sequential waypoints on; or within a minute or two; of flight plan. There was some convective weather en route which entailed deviations up to 50 nm left and/or right of course; which may have increased the burn. At the time that the relief crew took over flying duties from the Captain and First Officer (FO); the fuel burn was about 2000 pounds higher than planned. We were about 4 minutes behind flight plan; which was intentional; to avoid arriving at ZZZZZ Intersection early. On return from crew break; the relief crew advised that the trend in higher fuel burn had continued. It had also been exacerbated by an inability; due to ATC conflicts; to climb to a higher altitude; and by further weather deviations. The fuel at the refile point; had been 34;000 pounds which was slightly higher than the minimum required for redispatch; but substantially off the planned fuel of 38;000 anticipated at that point. We advised Dispatch of the disturbing trend in the fuel burn and mentioned the possibility of diverting into Brisbane which at that point showed fuel on arrival of 14;500. After deliberation between the crew; ATC and Dispatch; we elected to continue with a planned arrival fuel of 9;600. Given the excessive burn; and the perception by the FO that the plane had seemed heavier on take-off; we contemplated the possibility that the aircraft was indeed heavier than planned. The rationale for this consideration was that; if the standard passenger and baggage weights had been used for determining the weight and balance data for the flight; instead of using weights more appropriate to a [sports] team traveling with equipment and gear; it was indeed possible that the payload had been miscalculated; and that the aircraft the was possibly several thousand pounds heavier than indicated in the W&B data. The FO elected to land at a slightly higher reference speed than the computed data which; given our suspicion of the validity of the landing data; seemed a prudent idea. The arrival and landing was uneventful and we landed with approximately 8300 pounds of fuel; well below the planned landing fuel of 14;000 pounds. We compared our fuel burn to [a similar flight]; which was slightly behind us and on the same route; at a similar altitude and with similar weather deviations; and they reported their fuel burn of being more typical; with a positive trend of burning less fuel than planned. This suggested that our excess fuel burn was not due to any environmental factors; but probably due to being heavier than flight plan. We would appreciate if this incident could be passed to load planning; that they may consider if the unusual circumstance concerning the passengers and pay load of this particular flight; may have led to a miscalculation of weight and balance data.




Synopsis: Air carrier Captain reported a greater than planned fuel burn on an international flight; likely due to erroneous weight and balance calculations; along with deviations for weather.