Takeoff and landing performance, and the flight plan data is normally precalculated.. .. .The takeoff data is normally calculated for each runway in a book form taking into account the runway direction, slope, length etc and the obstacles after takeoff, and the optimum configuration that works for the runway.. .. .Some ball park fuel flows.... .. .Taxi fuel 300lb. .. .Climb fuel flow, 15000lb/hr@2000ft->8000lb/hr@39000 ft. .Descent fuel flow, 800lb/hr. .Cruise fuel flows. .1st hr 8400lb. .2nd hr 6000lb. .3rd hr 5600lb. .4th hr 5500lb. .5th hr 5400lb. .6th hr 5300lb. .7th+hr 5200lb. .. .Z