Archived

This topic is now archived and is closed to further replies.

sgreen91

Progress Page Fuel Remaining

Recommended Posts

I have submitted a ticket for this issue with PMDG as I am taking it is my system causing the issue; but if somebody could check something while in flight I would appreciate it.

 

Watch the fuel at destination on the progress page and see if it stays consistent at one value with maybe a .1 or .2 fluctuation.

 

On my 777 the fuel at destination from takeoff decreases  .1 every 31-33 nm.  So on takeoff for example the progress page says I should have 20.0 at KIAD.  In actuality by the time I arrive at the destination I have 12.6 which is almost 8000 lbs lower that what was at departure.    I have reinstalled the 777 but it did not fix the issue. 

 

Now before you say its winds I did this with the clear skies theme (as in the tutorial) so there was absolutely no wind at any altitude to cause fluctuations in fuel remaining but the fuel continued to loose .1 every 31-33 nm.  Even with wind it still  looses .1 every 31-33 nm.

 

I tried the same scenario in the NGX and it did not exhibit the same behavior.  At takeoff it said 5.6 I landed with about 5.2 if you take into account vectors etc.  It stayed stable throughout the flight with it predicting 5.3 at destination.

 

I understand there will be minor fluctuations but from takeoff to landing the progress page for fuel at destination changes almost by 8000 lbs in a no wind situation.

 

 

If somebody would be so kind  why they are on their long haul and nothing to do and think about it just watch the progress page and see if the fuel at destination stays stable over about 200 nm.  I would like to verify before reinstalling FSX completely.

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

Well I think wind is one factor to account for and I'm just guessing on the next part.  But other variable are present even in the absences of wind like temps aloft, atmospheric pressures, etc and the FMS can't only guess while at the gate.  Once in flight and actually in-taking the data of these other variable can it make a new prediction.  Again just a guess but these other variable do effect air fuel ratios and therefore fuel burn.

 

I have seen this myself but I don't think I've seen the amount to post and I've done 5 flights so far all 13 to 15 hours.

 

EDIT: On my flight now about 7 hours into it, HGK - ORD about an 14 hours flight time and 7 hours into it and only showing 1.3 or 1300lbs from at the gate prediction to what I have now.

Share this post


Link to post
Share on other sites

Thank you for the responses.  I'm 2.5 hours into KBOS to EGLL and progress fuel is down 4000 lbs from what it said at the gate.


Well I think wind is one factor to account for and I'm just guessing on the next part.  But other variable are present even in the absences of wind like temps aloft, atmospheric pressures, etc and the FMS can't only guess while at the gate.  Once in flight and actually in-taking the data of these other variable can it make a new prediction.  Again just a guess but these other variable do effect air fuel ratios and therefore fuel burn.

 

 

I agree but why is it that everyone says their fuel can be planned using the FMC.  If I did i'd run out of fuel at this rate.  Its almost like I have a fuel leak.  Even with a 100 kt tailwind I'm losing 100lbs per 30 miles on the prediction for landing.  In contrast with a 100kt HW i'd still be loosing 100 lbs per 30 miles.  Nothing effects the fuel going away.

Share this post


Link to post
Share on other sites

I'm using the FMS as my fuel planner until next week when I can get PFPX.  I'm also using AS2012 for weather injection as well making a [.wx] file to help the FMS 'look ahead'.  I've been planning a reserve of low 20,000lbs range.  FMS this flight said at the gate I'd arrive at ORD with 26.6 and now its at 25.3.  I too have a tailwind of 85kts but the FMS knew somewhat winds we undertake.

 

Not sure what weather injection you're using since it sounds like this flight you've got winds, but dose it seams like you're having warmer then relaistic aloft temps?  Or some other injected weather factor aloft playing with fuel burn.

 

I have 7 hours left on this flight 15:25z arrival time @ORD and will update the landing fuel I get. But I'm guessing once I enter the STAR into ORD and land without taxying to gate I'll have low 24,000 left and reserve this flight is 21.7.

 

Also I've been about a hour and no drop from the 25.3 predection still.  Under your last post I'd be around 25.0

 

EDIT:  I wanted to add that as soon as the FMS changes the recommend flight level for a step climb I do it. Most of the time its a good 400-500nm before the ND S/C icon.  FMS says now next step climb is at 9:29z but I can step up I'm guessing now around 8:xx something zulu time.  I do see positive number on landing fuel doing this.

Share this post


Link to post
Share on other sites

From what I hear yours is doing it looks as if I will need a reinstall of FSX.  I using auto cruise and since my last post the prediciton is down another 4000 lbs.  A total of 8000 lbs from departure.

 

Right now I'm using FSGRW but yesterday I used AS2012 and there is no difference in either or if I run clear skies theme.  Something in my setup is FUBAR with the 777 FMC and I'm not sure what in my FSX is playing havoc with it.

 

Thanks for all your assistance its greatly appreciated.   I will await my ticket from PMDG.

 

Enjoy your flight and safe landing.

Share this post


Link to post
Share on other sites

Just landed a shut down, over 14 hours in the air and landed with 24.3.  So this was only 2.3 off what the FMS had its prediction at ORD while at the gate a HGK.

 

So I not seeing the larger understatements you're getting.

Share this post


Link to post
Share on other sites