777-300ER C of G
 

Is there a way to calculate the CofG of the airplane in-flight? The landing x-wind limitations are based on the CofG. There's no obvious way that I can see/find.

Many of the FMS kits will do that for you. Otherwise, especially if you have a trimsheet loading system, you can adjust the fuel load progressively to see the inflight effect on CG or, if you are really keen, do it longhand.

The load sheet (depending on software) will typically show CG for TO, Ldg & ZFW.

Interpolate between TO & Landing for mid-flight, or…

Good luck.

You need to be careful interpolating as, often, the mean fuel arm varies with fuel quantity. Rerun with varying fuel loads will get the job done.

For the ER there should be CofG correction to the load sheet value of the MACZFW based on fuel quantity. It's a graph in the Supplementary Procedures section of the FCOM or whatever your procedures manual might be called. It's mainly used to update your max cruise altitude with the changing CofG with fuel burn in the cruise. The calculated value is entered in the crz cg (line 4R) on the perf page.

Why interpolate ? It’s going to land so use the Ldg CG.

If you have a plot of the envelope with the CG following the fuel use line, then just look at your current weight and see what the corresponding CG is.
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