Fuel Policy and Fuel Monitoring

Universal Application of Fuel Policy

You are shortly about to start practical planning examples on the Single-engine Piston, the Multi-engine Piston and the Medium Range Jet Transport aircraft. As you will find out, we enter various tables and graphs for these aircraft types and, from these, we are able to work out how much fuel will be used for a particular length of flight under different conditions of aircraft weight, air temperature and wind component. In general, these predictions are quite accurate as long as the meteorological conditions experienced are close to the forecast values used to produce the plan. We call this the Trip Fuel.

On its own, however, this is not enough. If we had just the trip fuel on board at the moment of take-off, the engine would stop because of fuel starvation the moment we arrived at the destination, which is obviously not an acceptable way to operate. Clearly, we need some fuel other than the minimum to just do the trip. After all, we start using fuel before take-off. We have to consider start-up and taxi. We also need reserve fuel, firstly in case the trip does not go as planned, and secondly in order to taxi in and shut down.

The principles which establish how much fuel should be carried on an air transport flight have been internationally agreed and are laid down in CS-OPS 1. Whilst the actual amounts vary from aircraft type to type, because different aircraft have different fuel consumptions, the rules by which the minima for each flight are calculated are universal.

This is known as EASA Fuel Policy.

Realistic Trip Fuel

Whatever the commercial pressures to carry minimum fuel, there is no point in coming up with an unrealistically low figure for trip fuel. It has to be based on what you actually expect to happen. This means taking into account, for instance, the most likely routing, rather than a straight line route from departure to destination. If the departure airport insists on Standard Instrument Departures (SIDs) or the destination airport insists on Standard Instrument Arrivals (STARs), as is normal, then the SIDs and STARs may add tens of miles of track distance to the en route portion of the trip. These should be included in calculating the trip fuel. In particular, the following points should be noted:

The operator shall ensure that the planning of flights is based only upon:

•Procedures and data derived from the Operations Manual or current aeroplane specific data.

•The conditions under which the flight is to be conducted, including:

•Realistic fuel flows expressed as kg/h, lb/h or gal/h;

•The aircraft’s anticipated weights (masses)

•Expected meteorological conditions; and

•Air Traffic Service procedures and restrictions

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NB: Taxi fuel NOT included in Total Endurance calculations

Contingency can be assumed to be unused

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EASA Fuel Policy - Breakdown of Fuel

Under EASA fuel policy, fuel is considered under the following breakdown:

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