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Old 14th Feb 2009, 20:19
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eckhard
 
Join Date: May 2005
Location: France
Age: 69
Posts: 1,143
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Hi n9xv

This is a reply I sent to a previous post about fuel planning. It may be useful to you; if not, I apologise.


Here are some notes which you might find useful. They are 'JAR-OPS generic' but I may have used some 'company-specific' terminology here and there:

FUEL PLANNING NOTES

TIF TRIP FUEL Fuel for take-off, climb, cruise, descent and approach at destination using forecast winds and planned Flight Levels on the route filed with ATC.

CONT CONTINGENCY 5% of TRIP FUEL to allow for unforecast winds, lower than optimum levels, ATC re-routes, etc.

DIV DIVERSION Fuel for go-around, missed approach, climb, cruise, descent and approach from destination to the alternate airport using forecast winds, levels and routing as listed on the flight log.

RES RESERVE Final Reserve sufficient for 30 minutes holding at 1500ft above the alternate airport.

REQ REQUIRED Fuel Required at the start of the take-off roll. It is the sum of TRIP, CONT, DIV and RES fuel. (Actually it is permissible to use CONT fuel before take-off, but unwise to use it all.)

DECMP DECOMPRESSION Not generally required for European operations. It is only relevant for long-distance flights over water (e.g. ETOPS). Sometimes referred to as ADDITIONAL Fuel

EXTRA EXTRA Extra fuel at the discretion of the captain to allow for holding at destination, anti-icing, etc. Can also include 'Tankering' Fuel.

TAXI TAXI Sufficient fuel allow for APU use, engine start and taxi before takeoff.

TANKS The Total of all the above. The fuel in the tanks before engine start.

Some other definitions:

FINAL RESERVE is enough for 30 minutes holding at the alternate airport (after diversion). If you dispense with an alternate (i.e. you 'commit' to landing at your destination), this is the minimum fuel that you must land with. If it is likely that the aircraft will land with less than this amount, you should declare a 'Mayday'.

TOTAL RESERVE is enough for a diversion to the alternate airport followed by 30 minutes holding. It is the sum of DIV and RES fuel. Sometimes called COMPANY MINIMUM RESERVES (CMR). Some companies have a 'minimum' CMR, e.g. 2000kg for a 737. I think this is the figure referred to in some posts.

PLANNED REMAINING is what you expect to land at the destination with. It is the sum of CONT, DIV, RES, DECMP and EXTRA fuel.

So you see there is no requirement to allow for 'holding' at destination. A sensible crew will take EXTRA fuel to cater for holding at destination, if they feel it is justified. On a 'normal' flight, they will arrive with PLANNED REMAINING, and so have some holding capability at destination in any case.

Hope this helps to clear up what can be a complicated subject (not helped by different terminology being used by different operators).
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