FF on Jets vs Turbo Props
Does anyone have a simple explanation on why Fuel Flow is lower on a turbo-prop at low altitudes than on a jet engine?
As far as I know, on short route sectors (low cruising altitudes) the burn of a turbo-prop regional aircraft may be down to half of a comparable Regional Jet.
I think I've got a general idea on why FF is high at low altitudes on a jet. (It is generally due to high density of the air, which requires more fuel. (...?))
I've also got a general idea on why a turbo-prop is relatively ineffective (=high FF) at high altitude. (It is due to low propeller efficiency in low density air.)
But why is the FF of a turbo-prop so (relatively) much less at low altitudes? It is still a jet engine driving a propeller?
Nick.