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Hi,

 

I creating my custom OFP using the Jetplan flight plan (using LAN Airlines format). I need to know which field type can I use to calculate the MDF: fuel and time.

 

According to our Jetplan OFP manual, MDF means the minimum fuel to go to the alternate airport which is the sum of trip fuel from destination airport to alternate airport and alternate hold fuel. Based on the attached photo, the MDF is as follows below for clearer understanding:

 

ALTERNATE   03504    01.25

HOLD ALTN   01200    00.30

MDF               04705    01.55

 

I read through the PFPX OFP manual but I didn't see anything that would satisfy the MDF calculation. Any suggestions??

 

Untitled-2.jpg

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  • 1 year later...

Hello,

 

sorry to revive an old thread, however it gives relevance. I too am trying to get this same figure, but to no avail.

I have tried to

 

1. make sure that the final reserve fuel (Final 30 minutes hold) is in fact seen as hold fuel. It does, because it auto-populates "Hold Time" in the Fuel Planning section.

2. I tried additionally to manually add a holding time of 30 minutes at the alternate airport selection fields when planning.

 

Even with both these holding fields filled in at 30 minutes, the field "<&AltnxFuel>" only gives my trip fuel. Nothing is added. I don't know where else to add 30 minutes

of holding fuel so a true diversion fuel is calculated per alternate.

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You'll need an OFP template that supports the entry adding a line for each, something like:

 

<&AlternateFuelSection_Begin>
<&AlternateFuelCaption> <&FuelAlternate> <&#[1]:13><&Altn1HoldFuel:6>  ........  <&Altn1HoldTime:5>
<&AlternateFuelCaption> <&FuelAlternate> <&#[1]:13><&Altn2HoldFuel:6>  ........  <&Altn2HoldTime:5>
<&AlternateFuelCaption> <&FuelAlternate> <&#[1]:13><&Altn3HoldFuel:6>  ........  <&Altn3HoldTime:5>
<&AlternateFuelCaption> <&FuelAlternate> <&#[1]:13><&Altn4HoldFuel:6>  ........  <&Altn4HoldTime:5>
<&AlternateFuelSection_End>

 

but this adds the 4 entries in the ofp, possibly could be filtered further

 

capture_001_11022021_092228.thumb.jpg.052b3cec4eb56b3d3aeaaa9b2c79f6d2.jpg

 

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Using the PFPX OFP and setting 30min holds in the alternate section does indeed add the fuel/time.

 

In this example with a two alternate requirement an additional 30min is added at ESOW in the summary, the furthest alternate of the two used

 

capture_002_11022021_104154.jpg.e94ffbf032e74d51b574ec2cefb2181e.jpg

 

capture_003_11022021_104218.jpg.cda3916e2dd2d612f8c64fc3515ef9fc.jpg

 

To get individual entries in the OFP will require a template edit

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Ok, understood, however now you have 30 minutes of final reserve PLUS 30 minutes of alternate holding. The 30 minutes final reserve IS the 30 minutes holding for whichever alternate you choose to use. In other words, if I have to add the alternate trip fuel to the Final reserve. Final Reserve is the final 30 minutes holding at destination. Whether it's your original destination or a new one (alternate).I am seeing a few possibilities, however it is going to take some very deep digging.

 

Thanks for your time...

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I have added a picture to aid in what I am trying to do. The fuel block is basically similar to its real life JetPLan modified counterpart. All quantities match except the alternate diversion fuel value (trip+final reserve) at the end of every alternate line. I have also added my fuel policy section pertaining to reserve fuel. "Hold over destination" and "Hold over alternate" are blank. Naming conventions have been updated to reflect the IRL counterpart. You will notice the FINAL RES line holding the 30 minutes of hold. You will also notice in my alternate section, I put in "FinResFuel" even though it is not accurate. Like this at least I can add the two values next to each other and know my required diversion fuel per alternate.

 

Cheers...

PFPX.png

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Would the <&MinReserveFuel> be what you're looking for?

 

It is defined as Alternate Fuel + Final Reserve fuel + ballast fuel.

 

So will generally be alternate fuel + 30 minutes in your case?

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VHOJT,

 

you're absolutely correct. However it only applies to the chosen alternate. i.e. Alternate 1. This is my current solution as of yesterday as a compromise. At least for the top alternate the value is correct. For the other three I have <&FinalReserveFuel>. It's three similar values, but allows me to quickly add the two.

 

Many thanks for you input.

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Hi,

 

I would take the alternate which is the further away, in your case altn 4 and that way you are sure to have enough fuel for any alternate and your final reserve fuel would leave you the choice to do what you like. Otherwise if you choose Altn 1 you would not have enough fuel if you have to go to altn 2,3 or 4.

 

Regards,

 

JP

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Hey JP,

 

it’s for the purpose of reproduction of the OFP. One can always make an airport which is not the closest ALTN-1 when planning your flight. Contingency fuel also helps keep options open. But I know what you mean and you make perfect sense.

 

X

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Hey MD-82,

 

Maybe it would work by adjusting the fuel policy to add fuel for an alternate and then during planning eliminate the automatically added 30 min hold fuel? 
Maybe this way it also then accounts for ALTN-2,3 and 4?

 

PB

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