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Old 2nd Jun 2006, 17:19
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Orp Tolip
 
Join Date: Mar 2005
Location: U.K, I think.....
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Apoligies if the following is incorrect, still a bit drowzy (as I was yesterday when I initially replied) from a stinkin cold but just realised that I missed one thing out from my original answer.
The Navlog systems I have used have always assumed CONT fuel is gone at arrival at destination (ie. on arrival at destination it assumes minimum fuel that being FINAL RESERVE + ALTERNATE). The main reason I can see for this is it makes the en-route fuel monitoring simple. At or abeam a waypoint you check fuel. If the fuel onboard is greater than on the Navlog you are up on your fuel plan, if its less then you are down. Idiot proof which with my limited capacity suits me.
As a result (and as Bealzebub and Flaps hinted at) on short trips with max payload you may have a reduced MTOW as we are landing weight limited. We therefore have to ensure that, if we do actually take off at this revised MTOW we actually burn the planned TRIP fuel (by which I mean only trip fuel (ie planned BURN)and not CONT fuel or any other additional fuel onboard) to be sure of meeting the MLW limitation.
It is that simple.
To take it one step further, MLW+PLANNED BURN- ZFW (or MZFW if planning Max payload) gives you MAX FUEL at Take Off without reducing payload). If this is LESS than the fuel figure provided by your planning system then either replan or reduce payload.
Now if your Captains aren't willing to simply modify the actual fuel loaded, burn off more en-route or stand up and get payload reduced in order to meet their legal obligations I think you have a serious Company culture problem that needs to be addressed. However its not the fault of the flight planning software... .
Having said that, as said earlier get it modified to assume CONT fuel isn't burnt and perhaps 'management' won't notice
What type do you operate? It seems stange to me that you can fly 6hrs with a full payload and still hit your landing weight limit unless you are tankering a huge amout of fuel or burn very little en-route. But then long haul for me is a 3 hour trip so what do I know....
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