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John Citizen
19th May 2018, 10:12
Hi.

I am just curious on other pilots thoughts on "minimum fuel on arrival at destination", assuming there are no other fuel requirements (alternate/weather/traffic/holding/contingency/icing/curfew/other). (payload permitting obviously)

Some pilots carry the bare legal/company minimum whilst others might carry a lot more extra (resulting in increased fuel burn).

Some pilots always carry extra/carry an alternate/holding whether it is legally required or not. Some pilots might only carry extra only if at night/single runway/intersecting runway destination/bad weather forecast/actually there.

Sure, there is no end of "what if..." scenarios which will require more than the minimum legal fuel but you can't just carry max fuel every flight (though I am sure some pilots do).

Is it wise to plan to arrive without sufficient fuel to divert to an alternate ? What if arriving during the day in VMC/CAVOK ? Has anyone ever been caught out by doing so ?

Just after some thoughts and ideas to assist with my own fuel making decisions.

Thanks for your replies.

(this does not include tankering fuel because of the price difference)

His dudeness
19th May 2018, 10:19
Is it wise to plan to arrive without sufficient fuel to divert to an alternate ? .

No, its not.

tescoapp
19th May 2018, 10:56
There are several approved alternate fuel planning methods. One of them if something like 12 conditions are met they can plan to not have an alt.

The different methods and rules for each one cover about 8-10 pages in part A fuel planning.


Its legal and if your MTOW or MLW when you arrive you really don't have much choice but to use it.

Are we happy using it.... not really... Will we take extra if we can.... hell yes.

But as its legal and no other safety issues outstanding, If you refused to accept the flight plan and off load freight just to have alt fuel you would be having a chat with someone.

Valid safety issue wx, historical expected traffic level etc not a problem asking to either recalculate with an alt and off load freight. But most if not all company's these days have huge databases with historical fuel burns including time of year and wx and its pretty accurate.

How much fuel does it save and hence money.... colossal amounts over a year we are told.....

Snakecharma
19th May 2018, 11:20
I think it is an important and requires more than a glib answer, BUT practically speaking it depends :)

Counter intuitively it may well be that the bigger the aircraft the more likely it is you won’t always have an alternate - or a real one at least. The reason I say this is for example the A380 (and to a lesser extent the 747 and 777) is not going to fit into every airport so the potential alternates become few and far between in some cases and the fuel required to carry an alternate is higher.

I note you are in Australia, so the lack of suitable airports drives a lot of decisions, whereas if you were operating in the US or Europe the decision making is different.

Perth for example is so far from anywhere useful that many carriers use “island reserve” or a version thereof.

in the machine I fly we carry technical alternates where we can and real alternates when necessary, and the times you need a real alternate it has a real fuel impost, though we can, under certain circumstances give the alternate away.

so to answer your question, a blanket, always carry an alternate answer isn’t necessarily the best or only answer

Meikleour
19th May 2018, 11:24
My take on this "old chestnut"

Over a forty plus year career I experienced more diversions due to blocked runways than due to weather. Most fuel policies are drafted in terms of what you can do/not do depending on how good the weather is. Now, when the weather forecast is good, then most aircraft tend towards carrying minimum legal fuel loads - couple this with much tighter landing spacings and you are now all set up for massive delays if a lander bursts a tyre or requires ATC to do a runway inspection etc.
Take for an example Gatwick (possibly the most busy, single runway, international airport in the world) - a 15 minute runway closure will typically result in up to 10 aircraft holding most of which will probably be carrying the same near alternate fuel! A situation that could so easily turn sour.

Chesty Morgan
19th May 2018, 11:44
“Minimum fuel” on arrival at destination includes alternate fuel (caveat isolated runways and whatever).

If you are talking about arriving at your destination with only final reserve then that’s a judgement call on the day.

pineteam
19th May 2018, 11:56
Minimum fuel in a nut shell means any unexpected delay and you will be burning your final reserve fuel eg 30 min in turbine engine. Minimum fuel does not include alternate fuel.
It was discussed here: https://www.pprune.org/atc-issues/323720-minimum-fuel-definition.html

and here: https://www.pprune.org/questions/607266-flying-b-minimum-fuel-2.html#post10150452

new_era
19th May 2018, 12:08
This is a very interesting topic because as Tony Kern said in his book Redefining the Airmanship we always can improve our level of skill from Safety, Effectiveness, Efficiency and Precision. Fuel management is an area in which we can make the improvement. From bringing always the same amount of extra fuel regardless of the wx, traffic, destination, fuel price…to an improved fuel management. We can discuss about a lot of good practices but I just want to mention one of them which is tankering.

Tankering is an interesting method when the fuel price at departure aerodrome is considerably less than at the destination. As you said you have to calculate if it’s worth it or not (extra fuel burn per 1000 kgs, cost of heavy landing weight,…) usually for short or medium haul it is interesting. You need to be careful also about the structural limitation especially max ldg weight.

That said, tankering offers 2 big advantages: cost saving and extra fuel in case of marginal weather or traffic congestion. Your stress level will be reduced in case of unexpected delay or marginal weather condition.

pineteam
19th May 2018, 12:09
Good Point New Era. We fly a lot to China. And fuel is really expensive there. I always ask the latest ZFW to carry as much as possible profitable fuel. Most of the time we carry so much fuel that we have enough for the return sector. That’s the positive thing when flying into China. :}

eckhard
19th May 2018, 12:42
I recently carried round-trip fuel from the UK to Angola in a 787. Fuel price must be very expensive to make it worthwhile on an eight-hour sector.

I think that Meikleour makes a good point about blocked runways versus weather. Although the regulations allow for dispatch without an alternate (in certain cases), I would consider it prudent to have a plan ‘B’ whatever the weather forecast.

Chesty Morgan
19th May 2018, 13:29
Pineteam that is the US definition for declaring low fuel. In ICAO you shall declare an emergency when your useable fuel on landing is calculated as less than FRF.

In your scenario any delay should not mean you are into your final reserve fuel. It could mean that you are using your alternate fuel.

Minimum planned and calculated en route fuel for arrival IS FRF plus ALT. However, it is perfectly acceptable and legal to continue to destination if your calculated fuel is less than FRF plus ALT.

Meikleour
19th May 2018, 13:40
Has no one else noticed the inconsistancy in most airlines attitudes to fuel burn?
a) carry the minimum fuel to reduce the burn and "save the planet".
b) tanker fuel to save money and thereby increase fuel burn and er.... "not save the planet"!!!!!

Denti
19th May 2018, 13:57
In general it depends a lot on where you operate. Unlike Meikleour i have never experienced a blocked runway (except for weather reasons, snow/ice/freezing rain) but plenty diversions due to weather, and i'm just two countries further in the middle of europe. Using statistical contigency fuel, which we we don't use in most cases, that alone is enough to not just go to the closest alternate, but chose from two to three different ones. Yes, theoretically we can plan without any alternate (if weather permits), but usually that requires a bit more fuel than simply going with one, and even than we can choose between a fuel alternate or more commercially/operationally fitting ones. Europe has an airport density that is simply more than enough for that. In more remote areas that is of course different, and as said above, if one flies a super, the number of available alternates dwindles quite considerably.

As usual, aviation cannot work without a certain flexibility on the day, and everything depends on where you are, where you are going, in which kind of equipment, in which conditions, both enroute and at the destination.

new_era
19th May 2018, 14:22
Has no one else noticed the inconsistancy in most airlines attitudes to fuel burn?
a) carry the minimum fuel to reduce the burn and "save the planet".
b) tanker fuel to save money and thereby increase fuel burn and er.... "not save the planet"!!!!!
Lol
Companies never care about environment. If they want you:
a) to carry the minimum fuel it is to burn less and "save few dollars"
b) to tanker it is to avoid refueling at some places where fuel price are high
Conclusion: both for economic reason

pineteam
19th May 2018, 14:39
Pineteam that is the US definition for declaring low fuel. In ICAO you shall declare an emergency when your useable fuel on landing is calculated as less than FRF.

In your scenario any delay should not mean you are into your final reserve fuel. It could mean that you are using your alternate fuel.

Minimum planned and calculated en route fuel for arrival IS FRF plus ALT. However, it is perfectly acceptable and legal to continue to destination if your calculated fuel is less than FRF plus ALT.










Hi Chesty Morgan,
Where you talking about US rules? I'm sorry I'm not familiar about US regulations.
What I said above is according to ICAO rules
From ICAO Annex 4444: Air Traffic Management.
-Minimum fuel: The term used to describe a situation in which an aircraft's fuel supply has reached a state where the flight is committed to land at a specific aerodrome and no additional delay can be accepted.

-The declaration of minimum fuel informs ATC that all planned aerodrome options have been reduced to a specific aerodrome of intended landing and any change to the existing clearance may result in landing with less than planned final reserve fuel. This is not an emergency situation but an indication that an emergency situation is possible should any additional delay occur.

AerocatS2A
20th May 2018, 08:54
Note that John Citizen is in Australia and a lot of the time fuel for an alternate is not legally required at all. You can be planned to a single runway and provided the forecast is ok then you can plan to get there with fixed plus variable reserve and burn through the variable reserve on the way.

As for what you should actually carry? Our company policy is to plan to land with 2000 kg (about an hour of fuel) assuming no other requirements. On a nice clear day/night I‘m totally happy with that and am comfortable burning into it a little bit. On a typical sector, if we were to plan minimum fuel we’d be landing with about 1200 kg including variable reserve. To my mind, that’s not enough, it only takes a single go-around and you’re looking at eating into fixed reserves, but 2000 kg, no problem.

There are a few times I would plan to have more than 2000kg. First, when it is required by the company fuel policy, i.e., weather below the alternate minima so an alternate is required and/or thunderstorms or traffic holding requires extra. Second, when it is not required but I‘m not happy. An example is when fog is forecast for after our arrival time. I have seen fog come in early often enough for that to trigger alarm bells in my head. When I want extra fuel but it is not legally required, I will discuss with load control to see how much can be taken without affecting payload. I may decide to take as much as that allows as that gives me divert options for as long as possible, or I may decide it’s worthy of offloading payload.

The reality is, particularly on the East coast of AUS, even if you don’t have enough fuel to get to an alternate, the amount of time you are committed to your destination is normally minimal.

In summary, I’m happy to go along with company policy, but if ever I feel like I need more, then I will take more. I’ve never been asked to justify my fuel load, but if I was and I couldn’t justify it, then it was a poor decision. In other words, I take extra when I have a reason to.

Meikleour
20th May 2018, 10:29
Denti: The point that we keep veering away from is this - when the weather is bad then most crews carry more than minimum fuel (eg. your wx diversions) HOWEVER the real problem is when the weather is really good and many operators press their crews to operate with minimum legal fuel laods. That is the very time when relatively minor delays can cause all sorts of grief when everyone is in the same position with respect to minimum fuel at destination.

new_era
20th May 2018, 11:32
If wx is good but I may expect some traffics or higher runway occupancy time due to closed taxiway or wip, I will take up to 500 kgs extra. As others said above you know more or less about your area and destinations. Some routes are very busy and sometimes you will be maintaining up to 5000 feet below the optimum level.

My company allows us to bring as much fuel as we want but just need to write the reason, but if one day the chief would say "wx is good, carry only minimum fuel" I will do that and I will fly normally (because everything is legal and safe) In case of unexpected event occurs, I will declare minimum fuel or mayday fuel as needed.

Stan Woolley
20th May 2018, 12:09
If wx is good but I may expect some traffics or higher runway occupancy time due to closed taxiway or wip, I will take up to 500 kgs extra. As others said above you know more or less about your area and destinations. Some routes are very busy and sometimes you will be maintaining up to 5000 feet below the optimum level.

My company allows us to bring as much fuel as we want but just need to write the reason, but if one day the chief would say "wx is good, carry only minimum fuel" I will do that and I will fly normally (because everything is legal and safe) In case of unexpected event occurs, I will declare minimum fuel or mayday fuel as needed.

Have you said what type you fly? Without knowing that, 500kg extra could be very different.

new_era
20th May 2018, 13:19
Have you said what type you fly? Without knowing that, 500kg extra could be very different.

I'm on the B737NG

mustangsally
20th May 2018, 16:52
It was always a rarity to see a planned dispatch fuel that was unreasonable. One time had a weather system developing over SEA that dispatch did not see. At that time our dispatch team was planning flights more than eight hours prior to planned departure. Talked with dispatch and additional fuel was not a problem.
Fuel is an expense that does Impact the bottom line. Diversions are also expensive to the company. When holding at destination I'm always listening for what the flights in front of me are doing as well as behind me. If they are heading to an alternate, where. If ten or fifteen are heading to the same diversion airport, holding at that arrival maybe required. So maybe making the decision early would be prudent. Many years ago, holding for Atlanta, lots of diversions were piling up, seemed Spartanburg was the favorite. We ended up diverting to Spartanburg and parked on the out side ramp area, all gates were long ago occupied. May have been thirty or more Atlanta diversions on the ground all blocking each other. Last one in was the first one out and so on down the line.
Back in the 80's we had "Full tank Frank," Always filled the 1011 up even if it left thirty or more paying passengers at the gate. Company finally bought out his retirement.