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JakobFB
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Fuel Policy and Route to Destination Alternate

Mon Jan 03, 2022 7:06 pm

Hi!

I'm interested in fuel policies used by different European airlines, and I've found answers to most of my questions online except for this:

EASA regulations* state that Alternate fuel should include (among other things):
"fuel for a missed approach from the applicable DA/H or MDA/H at the destination aerodrome to missed approach altitude, taking into account the complete missed approach procedure;"

I've seen a lot of real Operational Flight Plans and the alternate route seems to most often include either:
  1. a SID from the expected arrival runway connecting with a route to the alternate, or;
  2. a Direct from the expected runway to a waypoint connecting with a route to the alternate

Since the total track miles to the alternate airport also is listed on the OFP I've tried comparing the distances and found that most routes do not include track miles for the actual missed approach for the chosen runway, but rather extra miles added to the first leg (from runway to first waypoint), if a direct is used. I'm guessing it is to cover for vectoring. Including the complete missed approach seems like a good idea for some airports where they might be unavoidable, but for others where they would take you many miles in the "wrong" direction and radar vectors are expected anyways, they might just add unnecessary fuel. I believe I have read somewhere (unfortunately I no longer remember where), that the airlines could expect the pilots to ask for a vectored missed approach, or a direct towards the alternate if a diversion is expected in case of go around. Could this reasoning maybe be something the airlines can use instead of including the complete missed approach procedure in their routes?

Is the practice of not using the complete missed approach procedure perhaps something that the airlines competent authority can approve?


Best Regards,
Jakob

PS: I'm a hobbyist and not associated with real flight planning. It is just one of my interest :D
*Reference: Easy Access Rules for Air Operations (Regulation (EU) No 965/2012) — Revision 16, December 2021, AMC1 CAT.OP.MPA.150(b) Fuel policy, (a)(4)(A), (page 827)
 
113312
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Re: Fuel Policy and Route to Destination Alternate

Mon Jan 03, 2022 8:50 pm

I think you're getting too far into the weeds. Remember, alternate fuel is a planning exercise. You cannot make assumptions based upon a pilot request for vectors or different routing during the flight. It also should be considered that failure of communications will result in flying a full approach, missed approach, formal routing to the alternate and a full approach there. Of course, it you arrive at the destination and will not be able to land, the fuel necessary to divert to the planned or amended alternate can be reevaluated. Depending upon the rules of the operators certificate, this determination can be made by the Captain or jointly between the Captain and Dispatcher.
 
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zeke
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Re: Fuel Policy and Route to Destination Alternate

Mon Jan 03, 2022 9:17 pm

JakobFB wrote:
Hi!

I'm interested in fuel policies used by different European airlines, and I've found answers to most of my questions online except for this:

EASA regulations* state that Alternate fuel should include (among other things):
"fuel for a missed approach from the applicable DA/H or MDA/H at the destination aerodrome to missed approach altitude, taking into account the complete missed approach procedure;"

I've seen a lot of real Operational Flight Plans and the alternate route seems to most often include either:
  1. a SID from the expected arrival runway connecting with a route to the alternate, or;
  2. a Direct from the expected runway to a waypoint connecting with a route to the alternate

Since the total track miles to the alternate airport also is listed on the OFP I've tried comparing the distances and found that most routes do not include track miles for the actual missed approach for the chosen runway, but rather extra miles added to the first leg (from runway to first waypoint), if a direct is used. I'm guessing it is to cover for vectoring. Including the complete missed approach seems like a good idea for some airports where they might be unavoidable, but for others where they would take you many miles in the "wrong" direction and radar vectors are expected anyways, they might just add unnecessary fuel. I believe I have read somewhere (unfortunately I no longer remember where), that the airlines could expect the pilots to ask for a vectored missed approach, or a direct towards the alternate if a diversion is expected in case of go around. Could this reasoning maybe be something the airlines can use instead of including the complete missed approach procedure in their routes?

Is the practice of not using the complete missed approach procedure perhaps something that the airlines competent authority can approve?


Best Regards,
Jakob

PS: I'm a hobbyist and not associated with real flight planning. It is just one of my interest :D
*Reference: Easy Access Rules for Air Operations (Regulation (EU) No 965/2012) — Revision 16, December 2021, AMC1 CAT.OP.MPA.150(b) Fuel policy, (a)(4)(A), (page 827)


They would include the full route to the alternate, where you have assumed they are getting a direct to the initial waypoint I think you will find that will match a waypoint in the missed approach, ie the termination waypoint for the missed approach would be a start waypoint for the route. One of the assumptions made here is complete loss of communications, so the full route is planned.

Have a look on the internet for the the ICAO Flight Planning and Fuel Management (FPFM) Manual (ICAO doc 9976) that goes into some detail on planning alternates for various situations, including destination, enroute, EDTO etc.
 
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zeke
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Re: Fuel Policy and Route to Destination Alternate

Mon Jan 03, 2022 9:19 pm

113312 wrote:
Depending upon the rules of the operators certificate, this determination can be made by the Captain or jointly between the Captain and Dispatcher.


The OP was specially asking about EU ops, the FAA model of involving dispatches is not appropriate.
 
JakobFB
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Posts: 20
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Re: Fuel Policy and Route to Destination Alternate

Tue Jan 04, 2022 9:34 pm

zeke wrote:
They would include the full route to the alternate, where you have assumed they are getting a direct to the initial waypoint I think you will find that will match a waypoint in the missed approach, ie the termination waypoint for the missed approach would be a start waypoint for the route. One of the assumptions made here is complete loss of communications, so the full route is planned.

Have a look on the internet for the the ICAO Flight Planning and Fuel Management (FPFM) Manual (ICAO doc 9976) that goes into some detail on planning alternates for various situations, including destination, enroute, EDTO etc.


The loss of communications is a really good point that I haven't actually considered before!
Regarding the direct distance I have actually found OFPs that don't seem to include the full missed approach distance even when using a DCT.
I thought I could show some examples. Pilotseye, who make cockpit videos, have posted a couple of OFPs on their website.

1. In this Swiss OFP, LFSB is listed as the Alternate with route LSZH DCT GIPOL DCT HOC DCT LFSB (page 53-54)
The distance from LSZH to GIPOL is listed as 30 NM which in real life is ca 21 NM.
However, the arrival runway in LSZH is 14 which has AMIKI as missed approach fix for all approaches.

Interesting to me here is that the missed approach to AMIKI is over 25 NM long, and a direct from AMIKI to GIPOL is 41 NM. The distance from HOC to LFSB is also listed as 30 NM and is 9 NM in real life. It almost looks more like 10 NM added in the "departure" and 20 NM in the "arrival".

Usage of SIDs in the alterante route can be seen here:
- In this Lufthansa OFP, in the route from KLAX to alternates (page 9)
- In this Lufthansa Cargo OFP, out of EDDF to alternates (page 23)
Both KLAX and EDDF have missed approaches to a fix.

I'm don't understand why I'm not seeing the actual missed approaches included in the alternate routes if it's in the EASA regulations. Could I be missing something? Is there a reason why a SID (or direct) is used instead?

Best Regards,
Jakob
 
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glen
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Re: Fuel Policy and Route to Destination Alternate

Wed Jan 05, 2022 1:33 pm

It seems it is not so easy for the flight planning systems to perform this calculation automatically, as the missed approach procedures usually don't guide you into the airway structure like a SID.

Therefore we have an approved method, where the system plans the expeted route between destination and alternate and it adds a fixed manoeuvring distance for missed approach and arrival procedure. For all combinations of runways at destination and alternate it has been verified, the resulting fuel meets the requirements according the above mentioned regulation. If it is not the case for a specific airport, the procedure/fuel will be adapted by dispatch.
 
JakobFB
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Re: Fuel Policy and Route to Destination Alternate

Wed Jan 05, 2022 5:33 pm

glen wrote:
It seems it is not so easy for the flight planning systems to perform this calculation automatically, as the missed approach procedures usually don't guide you into the airway structure like a SID.

Therefore we have an approved method, where the system plans the expeted route between destination and alternate and it adds a fixed manoeuvring distance for missed approach and arrival procedure. For all combinations of runways at destination and alternate it has been verified, the resulting fuel meets the requirements according the above mentioned regulation. If it is not the case for a specific airport, the procedure/fuel will be adapted by dispatch.


That is really interesting, thanks!
Is there anywhere I can read more about this? I would be very interested in learning more about how the process works.

Best Regards,
Jakob
 
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T18
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Re: Fuel Policy and Route to Destination Alternate

Thu Jan 06, 2022 7:00 am

I do know off hand that the software I use will default a weight of fuel for MSAP - Missed Approach, when listing an alternate that set weight will be added to the burn to the altn via the prescribed routing. Granted this is for FAA not EASA but I know our software is also used for EASA approved ops as well. I will in situations where windshear could necessitate a missed approach add into our contingency another few units worth of our MSAP fuel weight to allow the crew additional approaches if required.
 
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zeke
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Re: Fuel Policy and Route to Destination Alternate

Thu Jan 06, 2022 1:18 pm

JakobFB wrote:
I'm don't understand why I'm not seeing the actual missed approaches included in the alternate routes if it's in the EASA regulations. Could I be missing something? Is there a reason why a SID (or direct) is used instead?


I dont know the company fuel policies for the airlines involved, however this is my guess at what you are seeing in each case

1) MIA-ZRH, this is an ETDO (ETOPS) flight, my guess is the figure CF on the 800 .10 is "critical fuel" or additional fuel that is loaded in order to meet for example a twin engine depressurized diversion. Once you have passed that critical point, that fuel then just becomes generic extra fuel which would be available for the diversion. The flight plan says that the diversion was not the critical fuel scenario.

2) FRA-LAX in a 747, looks like the used DEN as an enroute alternate which is early, they could have used something later. Again I think what is happening is the extra contingency fuel added is considered as extra fuel at the destination and the alternate again is the not the critical scenario. They landed with 10 tonnes where the minimum diversion fuel on the flight plan is 6.8 tonnes, so they have an extra 3.2 tonnes if fuel for maneuvering.

3) PAE-FRA this plan has a lot of extra fuel already incorporated, DEV 5339 1:12, so ontop of the 28 minutes to the alternate they have an extra 1:12 of DEV fuel.

So basically in the plans you have been looking at, the alternate is not the critical fuel scenario for any of them.
 
JakobFB
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Re: Fuel Policy and Route to Destination Alternate

Thu Jan 06, 2022 8:35 pm

I dont know the company fuel policies for the airlines involved, however this is my guess at what you are seeing in each case

1) MIA-ZRH, this is an ETDO (ETOPS) flight, my guess is the figure CF on the 800 .10 is "critical fuel" or additional fuel that is loaded in order to meet for example a twin engine depressurized diversion. Once you have passed that critical point, that fuel then just becomes generic extra fuel which would be available for the diversion. The flight plan says that the diversion was not the critical fuel scenario.

2) FRA-LAX in a 747, looks like the used DEN as an enroute alternate which is early, they could have used something later. Again I think what is happening is the extra contingency fuel added is considered as extra fuel at the destination and the alternate again is the not the critical scenario. They landed with 10 tonnes where the minimum diversion fuel on the flight plan is 6.8 tonnes, so they have an extra 3.2 tonnes if fuel for maneuvering.

3) PAE-FRA this plan has a lot of extra fuel already incorporated, DEV 5339 1:12, so ontop of the 28 minutes to the alternate they have an extra 1:12 of DEV fuel.

So basically in the plans you have been looking at, the alternate is not the critical fuel scenario for any of them.


Those are good points, and I agree all flights have a good amount of extra fuel.
But the way I understand the regulations is that the Alternate Fuel needs to meet the legal requirements without considering contingency or any other extra fuel, no matter if it "will" be available (like ETOPS extra). Basically, everything but the Alternate Fuel and Final Reserve Fuel* can be used during the flight to destination (and is planned to be able to be used), so the alterante fuel alone needs to cover for the entire alternate route including the missed approach procedure at the planning stage.

However, it still wouldn't completely explain why the missed approach procedure isn't included in (most) OFPs. I think the explanation by Glen makes a lot of sense in that regard.

*A slight difference is if the company fuel policy uses protected additional fuel - It could be possible for the company to have xx kg/min etc as additional fuel that is carried to the alternate.
I would happily be corrected on any of the above statements, should I be wrong.

Best Regards,
Jakob
 
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zeke
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Re: Fuel Policy and Route to Destination Alternate

Fri Jan 07, 2022 10:29 am

JakobFB wrote:
But the way I understand the regulations is that the Alternate Fuel needs to meet the legal requirements without considering contingency or any other extra fuel, no matter if it "will" be available (like ETOPS extra). Basically, everything but the Alternate Fuel and Final Reserve Fuel* can be used during the flight to destination (and is planned to be able to be used), so the alterante fuel alone needs to cover for the entire alternate route including the missed approach procedure at the planning stage.


Contingency fuel is considered to have been burnt, however buildups like for ETDO critical points are considered as being extra fuel available at the destination once past the critical point. For example if the critical point required an additional 30 minutes of fuel, that 30 minutes of fuel would be considered as being available at the destination. Another scenario is when the destination is also supporting EDTO, in that case you continue to go towards the destination after suffering a failure and legally not have the alternate fuel on arrival. The fixed reserve for a EDTO failure is less than the fixed reserve for normal operations.

The first flight plan had a comment in it that the alternate was not a fuel critical scenario.

JakobFB wrote:
However, it still wouldn't completely explain why the missed approach procedure isn't included in (most) OFPs. I think the explanation by Glen makes a lot of sense in that regard.


That routing we would call a FMC route. A lot of FMCs dont have the ability to store all the company routes and alternate routes (due to limited memory). A common way to manage this is they will only load the company routes into the aircraft database, and leave it up to the crew to insert the alternate route.

JakobFB wrote:
*A slight difference is if the company fuel policy uses protected additional fuel - It could be possible for the company to have xx kg/min etc as additional fuel that is carried to the alternate.
I would happily be corrected on any of the above statements, should I be wrong.


That is possible, and very common for close in alternates. Where we had close in alternates we had phantom track miles added to build up the alternate fuel.
 
bigb
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Re: Fuel Policy and Route to Destination Alternate

Fri Jan 07, 2022 2:58 pm

JakobFB wrote:
I dont know the company fuel policies for the airlines involved, however this is my guess at what you are seeing in each case

1) MIA-ZRH, this is an ETDO (ETOPS) flight, my guess is the figure CF on the 800 .10 is "critical fuel" or additional fuel that is loaded in order to meet for example a twin engine depressurized diversion. Once you have passed that critical point, that fuel then just becomes generic extra fuel which would be available for the diversion. The flight plan says that the diversion was not the critical fuel scenario.

2) FRA-LAX in a 747, looks like the used DEN as an enroute alternate which is early, they could have used something later. Again I think what is happening is the extra contingency fuel added is considered as extra fuel at the destination and the alternate again is the not the critical scenario. They landed with 10 tonnes where the minimum diversion fuel on the flight plan is 6.8 tonnes, so they have an extra 3.2 tonnes if fuel for maneuvering.

3) PAE-FRA this plan has a lot of extra fuel already incorporated, DEV 5339 1:12, so ontop of the 28 minutes to the alternate they have an extra 1:12 of DEV fuel.

So basically in the plans you have been looking at, the alternate is not the critical fuel scenario for any of them.


Those are good points, and I agree all flights have a good amount of extra fuel.
But the way I understand the regulations is that the Alternate Fuel needs to meet the legal requirements without considering contingency or any other extra fuel, no matter if it "will" be available (like ETOPS extra). Basically, everything but the Alternate Fuel and Final Reserve Fuel* can be used during the flight to destination (and is planned to be able to be used), so the alterante fuel alone needs to cover for the entire alternate route including the missed approach procedure at the planning stage.

However, it still wouldn't completely explain why the missed approach procedure isn't included in (most) OFPs. I think the explanation by Glen makes a lot of sense in that regard.

*A slight difference is if the company fuel policy uses protected additional fuel - It could be possible for the company to have xx kg/min etc as additional fuel that is carried to the alternate.
I would happily be corrected on any of the above statements, should I be wrong.

Best Regards,
Jakob


That usually because the miss approach is accounted for in Alternate fuel. At least it should be…
 
GalaxyFlyer
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Re: Fuel Policy and Route to Destination Alternate

Fri Jan 07, 2022 4:46 pm

There’s a famous PAA story in early 747 operations, KHOU-KJFK-to Europe. The dispatcher and captain used international fuel rules on the domestic leg, legally as it was international flight. Anyway, delayed in holding for JFK, radar outage, they head over to KEWR, given the normal loop north of NYC, west toward PA, to join the inbounds to KEWR. One engine flames out on final due to fuel starvation, two more before they made the gate and they stopped on the taxiway. A friend at the FAA investigated. At that time, plans were made with just the direct distance between destination and alternate.
 
JakobFB
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Re: Fuel Policy and Route to Destination Alternate

Sun Jan 09, 2022 4:41 pm

zeke wrote:

Contingency fuel is considered to have been burnt, however buildups like for ETDO critical points are considered as being extra fuel available at the destination once past the critical point. For example if the critical point required an additional 30 minutes of fuel, that 30 minutes of fuel would be considered as being available at the destination. Another scenario is when the destination is also supporting EDTO, in that case you continue to go towards the destination after suffering a failure and legally not have the alternate fuel on arrival. The fixed reserve for a EDTO failure is less than the fixed reserve for normal operations.

The first flight plan had a comment in it that the alternate was not a fuel critical scenario.

JakobFB wrote:
However, it still wouldn't completely explain why the missed approach procedure isn't included in (most) OFPs. I think the explanation by Glen makes a lot of sense in that regard.


That routing we would call a FMC route. A lot of FMCs dont have the ability to store all the company routes and alternate routes (due to limited memory). A common way to manage this is they will only load the company routes into the aircraft database, and leave it up to the crew to insert the alternate route.

JakobFB wrote:
*A slight difference is if the company fuel policy uses protected additional fuel - It could be possible for the company to have xx kg/min etc as additional fuel that is carried to the alternate.
I would happily be corrected on any of the above statements, should I be wrong.


That is possible, and very common for close in alternates. Where we had close in alternates we had phantom track miles added to build up the alternate fuel.


I'm not sure I fully understand. Doesn't the alternate fuel *alone* need to cover the entire alternate route? And this since extra fuel (incl. extra fuel leftover from ETOPS) and contingency all can be burned in the original flight. If that's not the case then wouldn't the extra fuel by definition need to be protected fuel, i.e. explicitly planned not to be used in the original flight? In your example, if ETOPS additional fuel is 800 kg and the required alternate fuel is 1200kg, would the alternate fuel be reduced to just 400 kg? Or would the 800kg be a part of the 1200? How is it ensured the 800 kg listed as ETOPS additional are not used during the original flight after ETOPS exit when it becomes normal extra fuel?

In the Swiss flightplan, I'm guessing you mean "OPTIONAL ALTN NOT ANALYZED FOR CRITICAL FUEL SCENARIO"?
In my understanding the comment is not about the actual alternate fuel, but about the fact that EDDS, LSGG,(and possible LIMC - fuel is not visible in the document) have a higher required fuel than LFSB. Since only LFSB is filed as alternate, the other listed alternates are for information only, and the reuqired fuel to fly to them is not added.

Getting back to the original question however:
The track miles listed in the alternate flightplans do not in all cases cover the complete missed approach procedures. How do european airlines ensure they meet EASA alternate fuel requirements when flightplanning?

Best Regards,
 
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glen
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Re: Fuel Policy and Route to Destination Alternate

Sun Jan 09, 2022 5:46 pm

The CF in the Swiss OFP means Company Fuel and means fuel prescribed by the company. The reason for the CF is not visible on the OFP but in the planning documentation.
In those years there was an issue with the Altnernate Planning in the Software. The CF on this specific example was indeed to cover the additional fuel for the Alternate and was protected, i.e. we had to carry it to the destination. This amount of fuel covered those additonal mileages the system adds automatically to the Alternate routing nowadays .
 
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zeke
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Re: Fuel Policy and Route to Destination Alternate

Sun Jan 09, 2022 9:15 pm

JakobFB wrote:
If that's not the case then wouldn't the extra fuel by definition need to be protected fuel, i.e. explicitly planned not to be used in the original flight?


That is correct, prior to the critical point in the flight plan that fuel must be protected in order to arrive at the enroute alternate and hold for 15 minutes.

JakobFB wrote:
In your example, if ETOPS additional fuel is 800 kg and the required alternate fuel is 1200kg, would the alternate fuel be reduced to just 400 kg? Or would the 800kg be a part of the 1200?


There would be 1200+800 available at the destination.

JakobFB wrote:
How is it ensured the 800 kg listed as ETOPS additional are not used during the original flight after ETOPS exit when it becomes normal extra fuel?


Its loaded in addition to the fuel required to complete the flight including the normal alternate, it is more common where the destination alternate is close to the destination.

Here is a hypothetical situation

If we look at the planning to the enroute alternate
Taxi -500
Trip to critical point - 10000
Diversion at FL100 to diversion airport- 15000
Hold for 15 min+approach+landing - 2500
Total - 28000

Basic calculation
Taxi - 500
Trip - 17700
Contingency - 2000
Alternate - 2000
Final reserve - 5000
Total - 27200

The basic fuel required is 27.2 tonnes, however in order to get to the EDTO alternate you need 28 tonnes, so an additional 800 kg of additional fuel is loaded ontop of the basic fuel. Once past the EDTO critical fuel point that additional fuel loaded becomes extra fuel.

JakobFB wrote:
The track miles listed in the alternate flightplans do not in all cases cover the complete missed approach procedures. How do european airlines ensure they meet EASA alternate fuel requirements when flightplanning?


How each airline does it will vary, the easiest way is to add some additional track miles or nominal amount of fuel for the alternate.

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