I've posted in your other thread, but:-

I'm trying to post my weight and balance on here in the hope that someone cleverer than I could advise which sums to put where in the SD form?

help mogas

Strangely enough the heading on my post was "Help please", not how would you like to be ridiculed on this forum, from: who bears the title "too much Forum".

Thanks, for not helping!

Again, all these data are in the POH. If you have a pilot license and access to the POH all of this should be pretty clear to you.

-- Chris.

Thanks for that, slightly clearer in my mind. where does one get the data to construct the polygon frame to match my aircraft (Grob 109B Motorglider)?

The data should just be in your PoH. You probably don't need to worry about CoG (lat) unless you're flying a helicopter, the CoG (lon) may also be labelled as empty weight arm or something similar. It's the distance from an arbitrary datum of the centre of gravity of the aircraft when empty.

I have managed to input all of the Aircraft properties in my SD, except the CoG (lon) and CoG (lat), could someone please give me step by step instructions on:

(a) where do I get this data from

(b) how to calculate it

(c) where do the lever arm calculations come from and how are they arrived at

Many thanks

Dave