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steekyrice20

low fuel temperature

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I see a low fuel temp in dash display. How can I fix it? With the upcoming winter schedule, I would like to know the procedure to fix this issue. fly lower? change fuel type? I remember this issue similar to the MD11s. The only thing I can do in the MD11 is to cheat the fuel type in the FMC. Any help appreciated.  :wub:

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Hi. If you go the the "PERF" page on the FMC, you can specify the minimum fuel temp. For most flights around the world using Jet-A1, this is -47 Degrees Celcius. Standard Jet A would be -37 or -40 depending on where you got it. If you were lucky enough to get Jet B, this would be -60, but I am not aware of any airlines that use Jet B, mostly military etc.

 

You can set your min fuel temp either during preflight when you fill out the PERF page, or access it later by going to INDEX and PERF. If you still have issues with cold fuel, you can fly faster, which increases your TAT (due to skin friction) or select a warmer altitude, which may or may not be lower than your current flight level. (that's a long story)

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If you want to do it the realistic way, increase your speed or change altitude to a warmer air mass by either descending or climbing.

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If you still have issues with cold fuel, you can fly faster, which increases your TAT (due to skin friction) or select a warmer altitude, which may or may not be lower than your current flight level. (that's a long story)

 

 

I flew a polar route that caused my EICAS to show Fuel Temp Issue, brought up checklist to see what the trouble was.  EICAS gave 2 solutions a) speed up b) descend to warmer air.  I chose to speed up, I was at .827 mach and sped up to .840 mach.  Within a minute, EICAS changed from Caution to Warning and within 10 minutes temperature dropped 1 degree and the EICAS warning extinguished.  I believe there are checklists for almost all EICAS warnings and cautions.


I flew a polar route that caused my EICAS to show Fuel Temp Issue, brought up checklist to see what the trouble was.  EICAS gave 2 solutions a) speed up B) descend to warmer air.  I chose to speed up, I was at .827 mach and sped up to .840 mach.  Within a minute, EICAS changed from Caution to Warning and within 10 minutes temperature dropped 1 degree and the EICAS warning extinguished.  I believe there are checklists for almost all EICAS warnings and cautions.

 

 

Forgot Sig

 

Norman Henderson


Norman Henderson

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Well done on the EICAS \ checklist items. You do need to ensure that you actually had the correct minimum fuel temp set however, as -37 (default) is less than the actual minimum for Jet-A1, unless Boeing sets it higher in order to give you advanced warning, PMDG would have to clarify this.

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Well done on the EICAS \ checklist items. You do need to ensure that you actually had the correct minimum fuel temp set however, as -37 (default) is less than the actual minimum for Jet-A1, unless Boeing sets it higher in order to give you advanced warning, PMDG would have to clarify this.

 

I noticed that when I went in to the perf page on the cdu.  I was showing -35 on the fuel temp when the EICAS issued its notice and the notice cleared when the temp went to -34.  Will the fuel actually begin to freeze in the sim, or can we just set the lower temp in the perf page with no worries?

 

Norman Henderson


Norman Henderson

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Good question Norman! That would be cool if PMDG modelled that. Try setting your external weather temp to, say, -99 degrees and seeming if it freezes after a while. I did an Air Canada flight from Finland to Vancouver and also got low fuel temp towards end of flight, it reached about -36 and stayed there almost till landing with no obvious issues. I was only about 1.5hours from TOD so didn't worry too much about taking drastic action.

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How can I fix it?

 

Bust out the QRH, or go to the CHecKList.  The nifty thing about the checklist, is that it'll automatically go to the page for the warning on the EICAS.

 

You bought a study sim.  It's going to require a little work on your part in terms of reading the manuals.

...or in the case of the 777, there's really no excuse: press CHKL, look at lower display unit, follow directions.


Kyle Rodgers

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Hi. If you go the the "PERF" page on the FMC, you can specify the minimum fuel temp. For most flights around the world using Jet-A1, this is -47 Degrees Celcius. Standard Jet A would be -37 or -40 depending on where you got it. If you were lucky enough to get Jet B, this would be -60, but I am not aware of any airlines that use Jet B, mostly military etc.

 

You can set your min fuel temp either during preflight when you fill out the PERF page, or access it later by going to INDEX and PERF. If you still have issues with cold fuel, you can fly faster, which increases your TAT (due to skin friction) or select a warmer altitude, which may or may not be lower than your current flight level. (that's a long story)

 

So to load in simulation regular Jet A all you have to do is change the Min Fuel Temp to -47 instead of the default which is -37?

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So to load in simulation regular Jet A all you have to do is change the Min Fuel Temp to -47 instead of the default which is -37?

Indeed yes, I am not sure why it is -37 in sim. If you are refuelling in most parts of the world other than USA, you would get JET-A1 which is -47. If you used JET-A, use -40. I believe JET-A is only used or available in some parts of the USA.

 

Interesting fact is that JET-A1 has a slightly lower density and there for energy density than JET-A, but we are talking less than 0.1MJ\kg.

 

If you are lucky enough to be flying in really cold parts of the world, you could use JET-B which is -60!

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Indeed yes, I am not sure why it is -37 in sim. If you are refuelling in most parts of the world other than USA, you would get JET-A1 which is -47. If you used JET-A, use -40. I believe JET-A is only used or available in some parts of the USA.

 

Interesting fact is that JET-A1 has a slightly lower density and there for energy density than JET-A, but we are talking less than 0.1MJ\kg.

 

If you are lucky enough to be flying in really cold parts of the world, you could use JET-B which is -60!

 

Thanks!

How can I get this as default? Save a panel state with it already set?

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Thanks!

How can I get this as default? Save a panel state with it already set?

Possibly, or just set it during FMS setup before each flight.

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