Loadsheet question

[FromAglantziaToJedda]

Any idea what the numbers at the bottom are used for? It looks like they are just the CG from the top multiplied by 4. But what are they used for?

[john_tullamarine]

A bit difficult with only a bit of the trim sheet to work with. If you post the whole trim sheet I can give you the answer. At present we don't have enough information to figure any sums.

With what you have given us, the numbers along the bottom should be the background moment or IU vertical scale to which any trim sheet is drawn. If you follow them right up to the top line where you start the IU calculations, you probably will find that the top and bottom scale line numbers are the same.

Perhaps you can post the whole sheet and we can resolve the problem very easily. (FWIW, over the past 60 years I have designed probably 400-500 trim sheets)

[FromAglantziaToJedda]

This is the whole trim sheet as it appears on the iPad application.

[FromAglantziaToJedda]

Here is the whole thing

[john_tullamarine]

Need a little more information. Can you post just the MAC % equation for me, please ? Probably in your ops manual weight and balance section.

[TBSC]

The upper scale is the CG in %MAC (MACZFW,MACTOW, MACLAW), the bottom scale is the Loaded Index (LIZFW/LOTOW/LILAW).

[First.officer]

I believe the scale you are referring to is the Aircraft Loading Index (LI).

Airbus aircraft use a Loading Index (LI) system to simplify weight and balance calculations, which is a scaled-down, non-dimensional figure representing the moment (weight multiplied by distance from a reference datum) of a load. It is used to ensure the center of gravity (CG) remains within safe operating limits throughout the flight.​​​​​​​