Mayday Fuel Assumptions
Thread Starter

Joined: Apr 2009
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From: Canada
Mayday Fuel Assumptions
The documentation indicates that Mayday Fuel is declared when you expect to land below final reserve. Sounds simple enough, but is this based on the assumption you will get a direct to final after the Mayday is declared? Or does it include a routing with more track miles such as a star? You could end up declaring a Mayday on the basis of flying an entire star only to be given a direct to final and end up landing significantly above final reserve. What would be the consequences of this?
Joined: Sep 2023
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From: HMP Slade
Some people think too much. If you believe you will land with less than final reserve then declare a mayday. If the situation should subsequently change in your favour, cancel it. Fill out ASR. Job done.
Joined: Jan 2022
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From: Miami
https://skybrary.aero/sites/default/...shelf/2376.pdf

Thread Starter

Joined: Apr 2009
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From: Canada
Neither situation reflects the level of urgency of the case in point:
Is it a situation of no contingency for unexpected delay? No.
Are you about to fall out of the sky? No.
But it is an urgency. and it has to be communicated. So declare a pan, give the reason and do not accept any delay. If given the run around or the controllers have odd priorities (common in exotic parts), THEN declare a mayday.
Is it a situation of no contingency for unexpected delay? No.
Are you about to fall out of the sky? No.
But it is an urgency. and it has to be communicated. So declare a pan, give the reason and do not accept any delay. If given the run around or the controllers have odd priorities (common in exotic parts), THEN declare a mayday.
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From: Cab of a Freight Train
If the situation improves after the declaration (Cleared direct, or planned holding cancelled for eg) then great, but that may not, and in fact, probably won't happen, unless you declare minimum or mayday fuel.
Originally Posted by The AIP
Emergency Fuel
The pilot in command must declare a situation of emergency fuel by broadcasting MAYDAY MAYDAY MAYDAY FUEL, when the calculated usable fuel predicted to be available upon landing at the nearest aerodrome where a safe landing can be made is less than the final reserve fuel.
The pilot in command must declare a situation of emergency fuel by broadcasting MAYDAY MAYDAY MAYDAY FUEL, when the calculated usable fuel predicted to be available upon landing at the nearest aerodrome where a safe landing can be made is less than the final reserve fuel.

Joined: Feb 2003
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From: Blue sky
When discussing this with others, something I always miss is the notion that the minimum fuel situation does not create itself "in an instant". It should be a result of many things that have happened already in which both you and the controller have been in contact and the situation is clear to both of you. The "commited to the airport" is already a pretty strong decision made prior in time, which means ATC gave you some kind of confirmation they should be able to get you in, otherwise you would have already been long gone on diversion.
As long as the controller's plans seems to get you in while you are keeping final reserve fuel in the tanks, that is fine, and you can let him control the situation. From the moment something changes (either longer time in the hold, adapted routing, weather changes,...) and you feel you need to take control over the flight path to protect your final reserve, you declare the mayday to give yourself that priority/"freedom". That doesn't stop you from giving him a signal ahead of course (like "unable STAR", he might give you a direct and the mayday might not be required)
Last edited by BraceBrace; 17th April 2024 at 11:51.
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From: Miami

Joined: Oct 2010
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From: 5° above the Equator, 75° left of Greenwich
Using a minimum fuel status will usually get a controller's attention as it is obvious that it is not frequently used and (in my experience) is likely to cause a sense of urgency. Others above have already been quite clear on how the regulation is intended and how to use it.
+1 on the overthinking. Don't assume a direct will be issued, you're already down on fuel. The thing doesn't fly too far without it and you're already (or will be) down to your last 30 mins, do you really want to push it that far? Something quite extraordinary has already happened to get you down to this point; I'd even go as far as declaring the emergency with a couple of minutes above my usual 30 if the situation might demand such a thing. It's fuel (and not too much of it left BTW), don't mess with it, follow the regulation, communicate as per the norm and, if necessary, err on the side of caution.
KRviator has pretty much summed it all up quite nicely, IMO





