Cruise CG B737NG

[Pin Head]

I remember there was a formula for the cruise CG by subtracting an amount ofF the take off CG on the B767 but is there one for the NG please?

Kind regards

Pin

[Denti]

We used to have a table with the delta CG depending on initial fuel load and remaining fuel for that in our QRH for the purpose of updating the CG around once every hour in cruise. However it was removed at some point as the difference in performance calculation was negligible.

Depending on fuel load the CG can move backwards and forward in one flight, it is not a linear relationship between CG and fuel on board.

[B737900er]

My company uses MACTOW - 4 for CRZ CG. Boeing said the worst case scenario is a 4% change in CG. This will change the margin for OPT/MAX cruising levels.

[Pin Head]

Thank you.

Is that written down anywhere in an official controlled Boeing document.

[lederhosen]

I agree with Denti's point that it is hardly worth the bother. The usual way you check the OPT/MAX is from the FMC. But if you are in ECON and then enter the exact same mach number you will get quite different OPT/MAX numbers. Enter a higher or lower MACH and you can massage the margin whichever way you want, which may or may not be a good thing, depending on whether you know what you are doing.

[B737900er]

Boeing release a magazine called Aero and thats where you can find some interesting topics.