Totally agree with you as far as you go Blackbird but remember, in the descent it is Fuel FLOW that is the same, but at slower speed the descent lasts longer (therefore a small increase in TOTAL DESCENT fuel burn in a slow speed descent) but that extra fuel burn is more than saved by starting the descent earlier than you would for a hi spd descent - thereby saving the fuel that would otherwise be burnt with the thrust levers at crz power prior to TOD for a hi spd descent - a significant net fuel saving. The whole point is that the position of TOD is affected by planned descent speed. At a planned Hi spd descent you have already burnt your 'extra' fuel prior to TOD. Ergo, planned slower speed descent = earlier TOD point = less time spent with crz thrust applied = fuel saving. Total cost is a different argument completely. For instance, tankering fuel. We do it to save money but it costs extra fuel.
Last edited by BANANASBANANAS; 15th Jul 2008 at 13:05.