w.i.p FUEL CONSUMPTION IN ME FLIGHT PLANNING

[Ahmed]

Noticed unusually high fuel burn against planned.

At a reasonable M .80 cruise at 25k in ISA with a DI 100 loadout and 46000 lbs:

- Expected FF: 6300

- Observed FF: 7900

That's a +25% error in an area of the envelope that should be quite commonly encountered, near optimum cruise aoa. Either FF or drag seem to be significantly off.

Ref: specific range chart for 25k 46klbs

Most likely other data points will render similar errors.

25k_M080_FF.trk

[BIGNEWY]

Fuel consumption review is currently in progress. 

thank you