Approach Ref anomaly

[fleurenf]

The Gross Wgt on the Approach Ref page of the fmc appears to be a manual entry.

The issue I've found if I enter the latest gross weight during flight and exit the Approach Ref page than enter that page, the Gross Weight reverts back to initial GW. I then have to re-enter the new GW each time I enter that page.

Any ideas on that?

Thanks in advance.

[Litjan]

The gross weight can be entered on the approach page to check "in advance" what kind of approach speeds you would expect (like when you do the approach in one hour or so) - accounting for burnt fuel until you actually will fly the approach. This is rarely used, but the way it works in reality.

Normally you are not supposed to EVER enter the gross weight or zero-fuel-weight after the initial setup. The fuel totalizer will add the current weight of the fuel to the zero-fuel weight (as entered by the pilot) and thus your gross weight will always show the correct, current value.