Fuel over destination
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If I were looking at 737 NG I would have thought that a sensible plan for your airline would be to 'PLAN' to arrive overhead with a minimum of 2000kg. This will give a comfortable margin over 'Reserve' which is normally around 1000kg and also put crews ABOVE the (ETOPS) fuel low-level warning of 1900kg at which there are QRH procedures to execute.
The whole idea of 'reserve' has grown up over the years to be the minimum you should have left when your flight has been 'disrupted' for whatever 'normal' reason, be it excessive burn, go-round, diversion etc. It was never intended to be what you planned to arrive with after an 'uneventful' flight. Representing 30 mins of flying (yes, to tanks 'empty') it gives time for that extra pattern or orbit to still have useable fuel left. I agree that puts 'pressure' on crews, but that is what all flying is about. In my opinion, to start carrying 2T extra every trip just in case an asteroid strikes or the wheels come off Aunt Mary's bicyle is impractical. Nice, but impratical.
All flying and planning is based, whether you like it or not, on statistical values. There is an 'acceptable' fatal accident rate in all forms of transportation - (bad luck if you happen to fall into it) and there are enormous numbers of flights that do not have humungous unexpected disruption at destination and just a few that do. On the 737 (Classic, anyway) the QRH calls for a minimum of 3800kg to attempt the 'no gear' drills - I'm not sure if they have EVER been called for, but even if once, do we now ALWAYS arrive with 3800kg 'just in case'?
The whole idea of 'reserve' has grown up over the years to be the minimum you should have left when your flight has been 'disrupted' for whatever 'normal' reason, be it excessive burn, go-round, diversion etc. It was never intended to be what you planned to arrive with after an 'uneventful' flight. Representing 30 mins of flying (yes, to tanks 'empty') it gives time for that extra pattern or orbit to still have useable fuel left. I agree that puts 'pressure' on crews, but that is what all flying is about. In my opinion, to start carrying 2T extra every trip just in case an asteroid strikes or the wheels come off Aunt Mary's bicyle is impractical. Nice, but impratical.
All flying and planning is based, whether you like it or not, on statistical values. There is an 'acceptable' fatal accident rate in all forms of transportation - (bad luck if you happen to fall into it) and there are enormous numbers of flights that do not have humungous unexpected disruption at destination and just a few that do. On the 737 (Classic, anyway) the QRH calls for a minimum of 3800kg to attempt the 'no gear' drills - I'm not sure if they have EVER been called for, but even if once, do we now ALWAYS arrive with 3800kg 'just in case'?
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BOAC
We have pressure from everyone these days. Do you think it's in the right direction? Are the line pilots calling for less and less fuel?
The average fuel load is decreasing so your 'statistics' are in new territory.
Read the ATC thread today (Go- Aound related)and you get an idea of what is going on after a bit of holding. (for a practical non-event)
Yes you can be lucky for a long time but as Mulligan implied instincts are often accurate.
We have pressure from everyone these days. Do you think it's in the right direction? Are the line pilots calling for less and less fuel?
The average fuel load is decreasing so your 'statistics' are in new territory.
Read the ATC thread today (Go- Aound related)and you get an idea of what is going on after a bit of holding. (for a practical non-event)
Yes you can be lucky for a long time but as Mulligan implied instincts are often accurate.
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Originally Posted by QT
and I doubt that anyone has varied their own view on fuel after reading what I think.
to get regulatory rules changed
adapt
change the company's doctrine
change companies
If you read my last post, I am not condoning the 'Mulligan scenario' in any way. In no way would I accept planning to land with those fuel levels. The ATC thread to which you refer rings no surprises for me - part of the problem is that all H F's company a/c at XXX would probably have been doing exactly the same - planning to land with RESERVES in that situation, a foible I pointed out to them on several occasions. Any crews engaging in such risky planning should ensure that they AND ATC are fully prepared for what is likely to happen - and did. ATC were absolutely correct and logical. The sensible thing would be for HF to have declared a PAN at the outset. ATC would then have had a better picture (but I would not envy them!). The same company will cross-file LHR and LGW as divs so you could end up with a/c with lowish fuel trying to swap between the two. Sensible - no! An element of commonsense (airmanship?) should prevail.
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and if your company says you are taking too much your options are
to get regulatory rules changed
adapt
change the company's doctrine
change companies
to get regulatory rules changed
adapt
change the company's doctrine
change companies
1) Yeah right!
2)Yes,a possibility. Should I just adapt to anything thrown my way and hope for the best?
3) Yeah right!
4) All airlines are heading this way.
The issue is that you MUST take what you deem to be sensible, no matter what others HERE think.
An element of commonsense (airmanship?) should prevail.
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Our contingency fuel is planned to be on board over destination. So our "burn" fuel includes fuel to carry the cont of 10 minutes minimum. So the absolute minimum we are planned to arrive with in a no alternate situation is 30 mins (state mandated) plus 10 mins contingency for a total of 40 mins. Just to refresh, on a 5 hour leg the other day my flight was planned like this. I ordered an extra 10 mins and also took off with an extra 3 mins of unburned taxi fual for a total of what should have been 53 mins over destination. I arrived with 40 mins so somewhere in that 5 hours I burned 13 mins of fuel more than planned. No deviations for weather and flight planned altitudes all the way except for an early descent to 360 from 390 which would have made a negligible difference.
It's getting too thin in my opinion and I see no reason why it won't get thinner as long as it "works" for long enough that it becomes normalized.
We live in an era where the rational method has triumphed over common sense and if anybody's interested I can recommend a book called "Voltaire's Bastards". by John Ralston Saul. A fascinating look at how this proccess has evolved over the last 300 years.
It's getting too thin in my opinion and I see no reason why it won't get thinner as long as it "works" for long enough that it becomes normalized.
We live in an era where the rational method has triumphed over common sense and if anybody's interested I can recommend a book called "Voltaire's Bastards". by John Ralston Saul. A fascinating look at how this proccess has evolved over the last 300 years.
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Our contingency fuel is planned to be on board over destination.
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Were the flight time/weights as per plan? In post 3 I mentioned that we were 500k lighter than planned. We were 1 to 2 minutes late over each checkpoint, not unusual.
Sorry, what's MLM?
If the aircraft is performing to spec then it seems to me that there is reason to to expect that cont will be there when you get to destination and there have been no deviations for weather or other fuel consuming contingencies. I agree there is no requirement for it to be there.
I'm guessing we are having a touch of "definitionitis".
Sorry, what's MLM?
If the aircraft is performing to spec then it seems to me that there is reason to to expect that cont will be there when you get to destination and there have been no deviations for weather or other fuel consuming contingencies. I agree there is no requirement for it to be there.
I'm guessing we are having a touch of "definitionitis".
Our contingency fuel is planned to be on board over destination.
So the absolute minimum we are planned to arrive with in a no alternate situation is 30 mins (state mandated) plus 10 mins contingency for a total of 40 mins.
Happy to be corrected.
Framer
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As Kissenger said: words are important.
When I said we "plan" to arrive with cont fuel I meant that our planned burn fuel is increased by enough to to carry the cont all the way to destination. It may or may not be there depending on the usual variables you referred to. Does that make it clearer?
When I said we "plan" to arrive with cont fuel I meant that our planned burn fuel is increased by enough to to carry the cont all the way to destination. It may or may not be there depending on the usual variables you referred to. Does that make it clearer?
Yeah thats clear to me thanks.
In my mind the end result is that your company is "planning" to arrive at destination with 30 mins fuel on board and any airborne delays at destination due to whatever (ATC, aircraft faults, runway problems such as go-round due aircraft holding on the threshold....anything) will put you into a situation where you are eating into your legal reserves.
Correct?
In my mind the end result is that your company is "planning" to arrive at destination with 30 mins fuel on board and any airborne delays at destination due to whatever (ATC, aircraft faults, runway problems such as go-round due aircraft holding on the threshold....anything) will put you into a situation where you are eating into your legal reserves.
Correct?
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Yes, if you have used all the cont enroute. The aim is to trim costs but the result for me personally is more intervention and more orders for extra fuel so the new policy is counterproductive in my case.
The policy uses statistical probababilities based on the previous two years fuel data for every leg we do. As I said in an earlier post I look at this as an almost superstitious belief in the rational method at the expense of experience, intuition and plain old gut feeling. These last three come under the heading of "quaint" or "unscientific" these days but I find they are becomming more important in my own planning.
After all, under our new system events like 911 and the Hudson splashdown become non-events two years and a day after they took place. Only a computer could think like that.
The policy uses statistical probababilities based on the previous two years fuel data for every leg we do. As I said in an earlier post I look at this as an almost superstitious belief in the rational method at the expense of experience, intuition and plain old gut feeling. These last three come under the heading of "quaint" or "unscientific" these days but I find they are becomming more important in my own planning.
After all, under our new system events like 911 and the Hudson splashdown become non-events two years and a day after they took place. Only a computer could think like that.
Cool, I'm with ya Mulligan.
The company has to assume, by law, that the contingency will by gone by the time you arrive at your destination so
should be taken out of the conversation/fuel planning etc. You have to assume that it is gone when you arrive.
This is , in my opinion, a mistake. Purely because any extra fuel used over and above the norm is a statistical improbability....thats when you want it, when something statistically improbably happens.
Ie if once every ten years a company aircraft uses an extra 40 mins of fuel after reaching their destination in order to safely complete checklists and deal with an emergency then it is worth having that fuel available. I'm not sayin they stay airborn for 40 mins....but that they use an extra 40 mins of fuel. Big difference. Very interesting situation your company is in. Planning to arrive with 30 mins flying time if everything goes well is asking for trouble, if it's not trouble this year, then next year, or the next or in 2016. It doesn't matter, and every year that passes in between the company (pilots included) will become more and more comfortable with the policy and then a plane load of people will die and everyone will ask "how did this happen?"
The company has to assume, by law, that the contingency will by gone by the time you arrive at your destination so
if you have used all the cont enroute.
The policy uses statistical probababilities based on the previous two years fuel data for every leg we do
Ie if once every ten years a company aircraft uses an extra 40 mins of fuel after reaching their destination in order to safely complete checklists and deal with an emergency then it is worth having that fuel available. I'm not sayin they stay airborn for 40 mins....but that they use an extra 40 mins of fuel. Big difference. Very interesting situation your company is in. Planning to arrive with 30 mins flying time if everything goes well is asking for trouble, if it's not trouble this year, then next year, or the next or in 2016. It doesn't matter, and every year that passes in between the company (pilots included) will become more and more comfortable with the policy and then a plane load of people will die and everyone will ask "how did this happen?"
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Hi Mulligan. My company also produces some flight plans with planned remaining fuel at Destination around 1500kgs (using close Alternates).
Do you realise that if you had an engine failure on finals (bird strike?), Go Around to sort out your problem, and simply follow ECAM, you will have 750 kgs of unuseable fuel? (Unless you disregard this ECAM - Please see A320 Fuel L+R Wing Tank Lo Lvl).
Should we have a QRH procedure?
Do you realise that if you had an engine failure on finals (bird strike?), Go Around to sort out your problem, and simply follow ECAM, you will have 750 kgs of unuseable fuel? (Unless you disregard this ECAM - Please see A320 Fuel L+R Wing Tank Lo Lvl).
Should we have a QRH procedure?
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Our company just reduced min fuel planned at destination from 10,500 Kg to 9,000 Kg for our 744s; 747 Classics remain at 10.5.
Combined with a new flight planning program, we are landing with MUCH less fuel than previously. The other day I had a 40 kt wind bust (170 kt headwind instead of 130) across the Pacific, and burned 2.6 more than planned in the first 1/3 of the flight.
We shut down with 8.9 instead of the 13+ planned. I'm very glad I had loaded about 2.5 more than the flight plan called for...
Combined with a new flight planning program, we are landing with MUCH less fuel than previously. The other day I had a 40 kt wind bust (170 kt headwind instead of 130) across the Pacific, and burned 2.6 more than planned in the first 1/3 of the flight.
We shut down with 8.9 instead of the 13+ planned. I'm very glad I had loaded about 2.5 more than the flight plan called for...
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Interesting to hear that one. I had a similar happening.
Ok, I'm going to try a survey and will start a new thread called Fuel over Destination survey. The more results the better.
Ok, I'm going to try a survey and will start a new thread called Fuel over Destination survey. The more results the better.
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Fuel over destination survey
I'd like to coduct an informal survey to try and ascertain how much various companies are shaving their fuel margins these days. If you want some background go to the thread Fuel over Destination.
To try and compare apples to apples I would ask any participants to simply state the minimum planned fuel over destination for a flight with no alternate. Please use minutes. I realize there are as many different approaches to this as there are airlines but I'm hopeful something useful will emerge. At my outfit it's 35 minutes "final reserve" plus 10 minutes "contingency". I used quotation marks because these terms mean different things at different companies. I trust everyone knows what I'm looking for.
I'll start the ball rolling............45 minutes
To try and compare apples to apples I would ask any participants to simply state the minimum planned fuel over destination for a flight with no alternate. Please use minutes. I realize there are as many different approaches to this as there are airlines but I'm hopeful something useful will emerge. At my outfit it's 35 minutes "final reserve" plus 10 minutes "contingency". I used quotation marks because these terms mean different things at different companies. I trust everyone knows what I'm looking for.
I'll start the ball rolling............45 minutes
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C-N - the OP asked for 'planned' fuel - is that what you are 'planning'? As pointed out, you cannot 'plan' to have contingency on arrival**. From your PLOG - (T Off fuel - trip fuel -contingency) is what we need.
EDIT: ** except when tanking to MLM
EDIT: ** except when tanking to MLM
Last edited by BOAC; 6th Nov 2009 at 08:02.
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Intruder - I am very surprised that your regulator (yes - I know
) is allowing both a 'new' planning system AND a reduction in arrival planned fuel without a reasonable statistical run.
It has been said before (by me and others) that the instant solution is to take planned fuel where it 'appears' correct and either divert or declare an emergency on arrival with ASR when it fails to work. All perfectly legal and 'correct' practice if that is what the company insist upon.
) is allowing both a 'new' planning system AND a reduction in arrival planned fuel without a reasonable statistical run.It has been said before (by me and others) that the instant solution is to take planned fuel where it 'appears' correct and either divert or declare an emergency on arrival with ASR when it fails to work. All perfectly legal and 'correct' practice if that is what the company insist upon.
