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767-300ER
23rd Mar 2023, 00:00
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.

john_tullamarine
23rd Mar 2023, 02:52
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.

awair
23rd Mar 2023, 03:45
The load sheet (depending on software) will typically show CG for TO, Ldg & ZFW.

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

Good luck.

john_tullamarine
23rd Mar 2023, 04:32
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.

sorvad
23rd Mar 2023, 17:54
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.

8che
24th Mar 2023, 00:38
The load sheet (depending on software) will typically show CG for TO, Ldg & ZFW.

Interpolate between TO & Landing for mid-flight, orÖ

Good luck.

Why interpolate ? Itís going to land so use the Ldg CG.

Dadanawa
7th Apr 2023, 22:08
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.
https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/850x770/68eb9b51_8843_41fd_a826_0186a46d02af_b89e4447340b10cd1a01d53 89a4010283ce9fa06.jpeg