Now, I don't have a copy of the POH but let me guess, the quoted arms are pretty close to 63.46 and 86.66 ?
The POH states the average center station for baggage area 1 is 64 and baggage area 2 84, so you definately nailed it.
= USG x 6 x 42 /1000
Just to be clear, you derived the 42 from the constant I gave you right?
Never mind sweptwing jets, any non-prismatic tank can be expected to have a fuel loading arm which varies with fuel volume - starting with small aircraft such as single Beech etc. The secret is to assess at what stage the aircraft is not reasonable for a linearised fuel loading arm.
That's the line of thought I was having, and you put it in great words. I thought that depending on the fuel tank, you just couldn't use a constant arm for it, since it could shift depending on the volume.
But as you put it, it doesn't apply to light aircraft such as C152's, 172's, 182's right? Since their fuel tanks are "standard" non-prismatic.
I actually thought of using the POH cabin arrangements section, which lists various stations from the firewall to the back of baggage area 2, to figure out the fuel tank station, since in this case the tanks are directly on the side of the pilot's seat. But in that case, the arm would be 39 (the seat stations range are from 33 to 41), and I just thought it wouldn't be right to do it that way, since it was not going to be accurate.
But John, you said we could just use a tape to measure it. So it can be done? I don't know how I would figure out the exact centroid for the fuel tanks, and couldn't know if the fuel tank cg would shift with different volumes in it.
And Mach Tuck, yes I see it now. It seemed to me that too many decimal digits wouldn't be derived by someone, it had to be written in somewhere.
And thank you for the FAA TCDS site, I did not know it. Will dig deep into it.