fuel calcl problem on the fmc

[cagrikartal 8]

hi everyone

 

im having this problem since quite some time, i discussed this in my other posts but i think it deserves its own topic as i cant understand the cause.

 

here is my quote from the other topic;

 

''and another problem im having  since i use my  panel state is that when i perepare for the flight, i put manually the amount of fuel then i go check other things. Some where after startup or during(sometimes) i get a ''insuficient fuel'' warning and in the perf page of the fmc the total fuel amount drops all by it self to some numbers and it says calcl just next to the fuel amount. Despite all, i have the right fuel amount on the upper eicas and on the fuel page of the MFP. After all i put the amount in the fmc pref page manually then it says manual next to the fuel amount  then everying become normal and i continue...

 

i dont know if this a problam or a tricky 777 system...''

 

 

thanks

[3-2-1-Now 126]

Known issue. Ticket has been raised and PMDG are fixing.

 

What is happening is at engine start, any fuel in the FUEL USED value (PROG PAGE 2) is subtracted from the calculated fuel onboard, when it zeroizes the fuel used for that engine.

 

e.g.

 

You have 25 tons onboard. In the PERF page FMC says 25.0 CALC.

 

PROG PAGE 2 used fuel for each engine states 2.0 (4.0 TOTAL).

 

You start engine #2. FUEL USED 2.0 resets to 0.0, TOTAL drops to 2.0, but fuel onboard as calculated by the FMC is now also reduced by 2.0 to 23.0!!!!! In this case, after starting BOTH engines, FOB will be computed as 21.0.

 

After engine start, go to the PERF page and manually re-enter the fuel onboard value as stated by the totalizer.

 

Best regards,

Robin.

[cagrikartal 8]

Known issue. Ticket has been raised and PMDG are fixing.

 

What is happening is at engine start, any fuel in the FUEL USED value (PROG PAGE 2) is subtracted from the calculated fuel onboard, when it zeroizes the fuel used for that engine.

 

e.g.

 

You have 25 tons onboard. In the PERF page FMC says 25.0 CALC.

 

PROG PAGE 2 used fuel for each engine states 2.0 (4.0 TOTAL).

 

You start engine #2. FUEL USED 2.0 resets to 0.0, TOTAL drops to 2.0, but fuel onboard as calculated by the FMC is now also reduced by 2.0 to 23.0!!!!! In this case, after starting BOTH engines, FOB will be computed as 21.0.

 

After engine start, go to the PERF page and manually re-enter the fuel onboard value as stated by the totalizer.

 

Best regards,

Robin.

 

okay, 

thank you for your help...