your the engineer. I'm joe shmuck. look it up in your notes.
cheers.
In my opinion from years of couciling it also appears that you have a self-esteme problem too.
I, for one, would like your explanation of scale weight. You have my attention.
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I went back over his number and I think it stems from a decade old concept out of the large scale world that was also hinted at one of the other posts here having to do with length area and volume (which, in this case, also refers to the weight, because it can be thought of as a density, a cubic dimention) when scaled down have to be done linerly, by the square and by the cube of the scale factor.
In his 8,000# 1/7 scale P-40 example Experten took 7 cubed or 343 and divided into the original weight 8,000# and came up with 23.32.
When you do this you get what he presented; at that weight this "scale weight" theory you will end up with ball park performance figures for model airplanes.
As a demo lets look at something a little easier to get actual numbers for a Cessna 182
1:1 scale
Wingspan 36' or 432"
Wing area: 174 sqft 25,056 sqin
Gross Weight 3,110#
Stall speed 56 MPH.
Top flight kit
Wingspan 81"
Wing area: 906 sqin kit computed = 25056/28.41 (5.33 squared)=881.9 sqin makes sense that TF would fudge the area a bit
Scale 432/81= 1:5.33
Scale weight= 5.33 cubed 151.5 divided into original weight = 20.53 Pounds, which is twice the listed weight for the TF C-182, but it should be able to fly at that weight but I doubt very much that it will fly as slow as 10.5 (56/5.33) MPH at that speed.
Like I said it gives you ball park numbers to work with
MTC YMMV