I did a test at different speeds and CIs and found the following: M.780 ~ 1300 kg/hr (per engine) CI 10 ~ 1320kg/hr CI 160 ~ 1340 kg/hr M.840 ~ 1390 kg/hr I did my best to let the engines stabilize before noting the values. I think that the fuel flow spread across the speed range is way too small and should be looked at. This also affects fuel predictions, as in this case it seems that the gained time outweighs the higher FF when increasing the speed. Here, a bigger increase in FF with speed (engine output) would be required to restore normal FF ~ speed ~ flight time relationships. Would it be possible to look into this issue?