PDA

View Full Version : C 0f G envelope versus Load Sheet


Stik
13th Mar 2007, 18:41
I didn't want to hijack the currecnt load sheet thread with this slightly off topic question . .

If I have a load sheet from a POH, is it possible to construct a C of G envelope for the same craft, without knowing the arms of the various stations? I dont know what the Index Units, or original datum are either.

The sheet starts off with ''empty moment'' ,then moves down to 'pilot & passenger'', ''fuel'', then ''luggage'' and then into the total weight area, with a shaded area showing acceptable W & B.

I just find it easier to use . . . the C of G envelope , I mean 'cos I have a program on my PDA!

( I think I read a thread asking the opposite question a while back ... )

Cheers

BackPacker
14th Mar 2007, 09:33
I don't know what the load sheet looks like, but I guess you could get the arms of the various stations by dividing the x axis through the y axis (or the other way around). Or something like that.

Just remember: moment = mass times arm. So mass = moment / arm, or arm = moment / mass. Your load sheet should have two of the three parameters, so the third one is easy to calculate.

What aircraft are you talking about? Although the empty mass and arm will vary amongst planes, the datum of the plane and the arms of the various stations will most likely not. Perhaps someone on this forum has the data for your type of plane already?