Fuel Imbalance

[AndrewB 7]

Hi All,

 

I have complete 4 flights with the 747 and each time i get a Fuel imbalance yellow warning

 

here are the tank readings

 

Main 1 13.3

Main 2 9.8

Main 3 9.8

Main 4 13.3

 

No yellow lights on the overhead panel

 

Thanks

 

Andrew B

[scandinavian13 5,192]

 

 

I have complete 4 flights with the 747 and each time i get a Fuel imbalance yellow warning

 

This happens when you ignore the TANK/ENG warning on the EICAS.

 

When you see this, you will need to turn off the OVRD tanks on the inboard tanks, and then close the outer (unguarded) crossfeeds. The tutorial flight references this.

[AndrewB 7]

This happens when you ignore the TANK/ENG warning on the EICAS.

 

When you see this, you will need to turn off the OVRD tanks on the inboard tanks, and then close the outer (unguarded) crossfeeds. The tutorial flight references this.

Got it 

 

thanks

Andrew

[77west 139]

I got this on my first flight. Quickly figured it out (I had just forgotten, in my haste). Reconfigured all engines to the tanks with the higher fuel level until it was evened out, and the imbalance warning went off, then went back to tank to engine mode.

[Piotr007 164]

 

The imbalance does not go away. It remains. I tried different combinations. First the one Kyle said. Turn off OVRD tanks and outer unguarded Xfeeds.

[downscc 1,327]

Peter, you are jumping onto an old thread without explaining your problem.  What are your tank readings and how are the pumps/xfeeds configured?

Basically, you pump fuel from the tank that has too much until it is drawn down to the level where all is balanced.

[Budbud 227]

Hi Peter,

In addition to Dan's post a few screenshots of the following would be useful:

_ Overhead fuel control panel

_ Upper EICAS (after pressing the RCL button on the DSP)

_ Lower EICAS on the fuel page

 

Also, if you are not familiar with the fuel management on the B747 (as it sounds from your post), the following may help you:

_ First:

_ FCOM, Fuel system operation, 12.20.13

_ FCOM, Supplementary procedure, fuel balancing SP.12.1

 

[scandinavian13 5,192]

2 hours ago, Piotr007 said:

 

The imbalance does not go away. It remains. I tried different combinations. First the one Kyle said. Turn off OVRD tanks and outer unguarded Xfeeds.

Of course it doesn't if you simply follow the procedure that I listed. The procedure that I listed is to prevent the imbalance and not solve it.

To clarify my above post:

Quote

 

This happens when you ignore the TANK/ENG warning on the EICAS.
Note that I am referring to the cause of the imbalance, and not the imbalance itself.

When you see this, you will need to turn off the OVRD tanks on the inboard tanks, and then close the outer (unguarded) crossfeeds. The tutorial flight references this.
"This" related to the first point (ignoring TANK/ENG) would of course be referring to the TANK/ENG warning on the EICAS.