Originally Posted by
Lantirn
Hello everyone.
Final reserve is a planning figure for 30 mins required for dispatch, lets say for the A320 its around 1100kgs.
I am wondering if that should change inflight if one encounters fuel penalty failures inflight.
Lets say you lose green hydraulic fluid and after gear extension you cant retract it and you have to divert to a close airport (not your day). So you have increased fuel consumption, almost double. Leveling off you realise that you burn around 4000kg/hr.
Does the "planning" fuel value of 1100kgs for landing still applies as a threshold for fuel mayday declaration? Or you factor the fuel penalty and make that mayday call threshold at 2000kgs to adjust?
Obviously you will declare urgency or emergency in bad weather under time pressure with technical issues for other reasons and the fuel mayday may come late towards the end of the flight.
But my question is more academic. Are you obliged to adjust the final reserve fuel value for the emergency fuel declaration with increased fuel consumption?
My guess is that you should adjust and count the FPF because ATC has an estimate of your endurance from your flightplan. Declaring a fuel mayday late would compromise safety.
Have searched ICAO FPFM (9976) and Annex 6 but still nothing there.
Hi,
the mayday fuel is time based, hence whatever increases your fuel consumption (gear stuck down, slats/flaps and so on) will affect how much time you can be in the air with a given amount of fuel. You will need to reassess all your critical fuel scenarios such as the final reserve fuel for instance. On the A320 a single hydraulic failure is not an emergency but the inability to land with at least 30 min of fuel in your tanks (if that is the case) will become one, like in your example.