What is the legal amount of fuel to takeoff?

[extricate]

Hi,

Anyone can point me to the right place where I can find information on the legal amount of fuel to takeoff from the point of dispatch?

I'm thinking of a scenario where ground delay leading up to holding point caused my contingency fuel and taxi fuel to be wiped out. I'm left with Trip fuel, Alternate fuel and Final Reserve (30mins) fuel, is it still legal to takeoff?

Thanks!

[vilas]

There is a discussion going on besides there are old discussions. You can search for them.

[blind pew]

Depends what you company allows but you can always plan a different destination with your planned destination as alternate and do a technical diversion in flight as long as you have the proscribed WX minimum. Was used a lot because of the limited range in the 80s.

[Stanley Eevil]

Hi,

Anyone can point me to the right place where I can find information on the legal amount of fuel to takeoff from the point of dispatch?

I'm thinking of a scenario where ground delay leading up to holding point caused my contingency fuel and taxi fuel to be wiped out. I'm left with Trip fuel, Alternate fuel and Final Reserve (30mins) fuel, is it still legal to takeoff?

Thanks!

IMHO, yes - you go! You should have your contingency fuel at dispatch but can then burn it all prior to T/O.
Are you really going to return to stand to ask for a top-up of about 1000 kg?

[AerocatS2A]

IMHO, yes - you go! You should have your contingency fuel at dispatch but can then burn it all prior to T/O.
Are you really going to return to stand to ask for a top-up of about 1000 kg?
I agree that legally you can go, however I would also suggest that it is sometimes prudent to go back for a top up even if not legally required. Sometimes legal minimum is not much fuel, particularly if you were not required to carry alternate fuel. I was in a situation a while back where the airport became unexpectedly fogged in and they weren’t issuing take-off clearances until some work vehicles had been removed so that LVOs could be put in place. Capt and I agreed on a minimum fuel we were happy with which happened to be more than min required due to short sector length and no alternate requirement. 20 minutes later we told ATC we were going back for a top up.

[extricate]

I searched and found this in ICAO Annex 6

"4.3.6.5 A flight shall not commence unless the usable fuel on board meets the requirements in 4.3.6.3 a), b), c), d), e) and f) if required and shall not continue from the point of in-flight re-planning unless the usable fuel on board meets the requirements in 4.3.6.3 b), c), d), e) and f) if required."

where a: Taxi Fuel, b: Trip Fuel, c: Contingency Fuel, d: Destination Alt Fuel, e: Final Reserve Fuel

[EGPFlyer]

I searched and found this in ICAO Annex 6

"4.3.6.5 A flight shall not commence unless the usable fuel on board meets the requirements in 4.3.6.3 a), b), c), d), e) and f) if required and shall not continue from the point of in-flight re-planning unless the usable fuel on board meets the requirements in 4.3.6.3 b), c), d), e) and f) if required."

where a: Taxi Fuel, b: Trip Fuel, c: Contingency Fuel, d: Destination Alt Fuel, e: Final Reserve Fuel

and ‘flight’ commences when you start to taxi therefore you can burn contingency in the taxi. At takeoff you need trip fuel, alternate fuel (if applicable, otherwise extra fuel as per no alternate procedures) and final reserve

[Piltdown Man]

Now define the commencement of flight for file planning purposes. Any such definition had been removed from our manuals. Therefore in my case I believe for fuel planning purposes flight starts the moment the first drop of fuel is consumed. So is it legal to take off? I think it is. The important question though is it sensible to do so? Given the right circumstances I might, but that is not the question the OP asked.

PM

[sonicbum]

Hi,

Anyone can point me to the right place where I can find information on the legal amount of fuel to takeoff from the point of dispatch?

I'm thinking of a scenario where ground delay leading up to holding point caused my contingency fuel and taxi fuel to be wiped out. I'm left with Trip fuel, Alternate fuel and Final Reserve (30mins) fuel, is it still legal to takeoff?

Thanks!

As others have said, yes it is legal but as 99% of the times there is a fuel discussion legality and sound judgement can quickly split up. To be legal You basically need to land anywhere with at least 30 min of fuel in the tanks or more according to regional regulations (EASA vs FAA etc..). Sound judgement contemplates the fact that You want to complete the flight from A to B safely with margins for reasonable* "what if scenarios" especially in period of deteriorating weather conditions and/or high traffic volume at destination.

*I was recently planned with 1st alternate being the closest one and a NOTAM stating that due to limiting parking space available the diversion could not be assured, on top of that NPA only... destination single runway with NPA only, weather ok but gambling in aviation is generally not working well, so I took fuel for the next alternate, nice big airport with an ILS and plenty of parking (uh uh !).

[vilas]

Therefore in my case I believe for fuel planning purposes flight starts the moment the first drop of fuel is consumed. If that is so then why is taxi fuel separately calculated and provided for? And therefore contingency fuel is for unforeseen circumstances after takeoff. It can't be burned before takeoff.

[extricate]

If that is so then why is taxi fuel separately calculated and provided for? And therefore contingency fuel is for unforeseen circumstances after takeoff. It can't be burned before takeoff.

Contingency fuel can be used up on ground, not only in the air.

[vilas]

Extricate
you are right. According to ICAO Flight Planning document: Fundamentally, contingency fuel is the fuel required to compensate for factors that could not be foreseen during flight planning. Such factors include, but are not necessarily limited to deviations from flight plan that could influence the total fuel consumed en-route to the destination such as:
 deviations of an individual aeroplane from the expected fuel consumption data;
 unforeseen meteorological conditions;
 unexpected taxi times before take-off;
 unplanned or unanticipated routings and/or cruising levels.

[Piltdown Man]

If that is so then why is taxi fuel separately calculated and provided for

Because you could already have done the taxiing. But anyway, the figure is notional. And where is the APU fuel burn allowance? TA has it spot on.

Soon we will learn exactly when a flight commences for fuel planning. Will it be APU start, push, first engine start, taxi start, taxi end, take-off power set, start of take off roll, wheels up... Will Paddy Power be running a book on this one?

PM

[vilas]

From ICAO Doc 9976
Occasionally, unpredicted prolonged taxi times may consume the planned taxi fuel and burn into the contingency fuel leaving the flight crew with fewer options, once airborne, to compensate for any other unforeseen factor(s). The PIC, in making the decision to continue a flight, must consider this
and all other operational factors that may affect his or her ability to safely complete the planned operation and protect final reserve fuel.
In the case of unforeseen taxi delays, for example, it may be possible to take-off having burned into the contingency fuel in order to avoid a very long delay. Conversely, a return to the gate for more fuel may be prudent if continuing the flight means having to make a fuel stop prior to reaching the intended commercial destination.

[pattern_is_full]

Exactly - an unexpectedly long taxi time (or any other unexpected delay between engine start and reaching the runway hold line) is a contingency, for which the contingency fuel is available and intended.

It does mean that if there are additional contingencies once on the air (everything goes fruit-shaped: unforecast headwinds, 100nm diversions around weather buildups), that the contingency margin will be less, so keep it in mind as the flight progresses.

[extricate]

Thanks all for the replies. Looks like there's only regulation governing fuel requirements for a flight and NOT fuel requirements before takeoff. Essentially, you could run down taxi and contingency fuel or even dip into alternate fuel (worst case but unwise) prior to takeoff.

[ph-sbe]

and ‘flight’ commences when you start to taxi therefore you can burn contingency in the taxi. At takeoff you need trip fuel, alternate fuel (if applicable, otherwise extra fuel as per no alternate procedures) and final reserve

I was going to comment exactly the same. The flight starts when the aircraft moves under its own power, so legally you should be good. But, one very big caveat: do you want to take off?

It's the same thing as out there in the club: if you have to ask yourself if she's legal, you better not take her to your room :)

[nike]

Your fuel build up is based on your CFP and company policy. Your route knowledge and awareness of any differences between what is on the CFP and what you are likely to actually fly all add into the mix as to whether you would get airborne after a lengthy taxi delay. As would the length of flight.... A 16hr flight provides both the opportunity for fuel gains above CFP figures due airborne efficiency opportunities as well as a tech stop to top up the gas should you not gain any fuel along the way. A 1hr flight with potential destination ATC delays and/or potential weather related delays would potentially drive a decision to return to bay for more fuel.

[extricate]

Thanks all for the replies. Looks like there's only regulation governing fuel requirements for a flight and NOT fuel requirements before takeoff. Essentially, you could run down taxi and contingency fuel or even dip into alternate fuel (worst case but unwise) prior to takeoff.

Thanks for the replies. As mentioned above, I understand the risks involved but I just want to know if there are regulations governing this grey area?