Plan Resizing
I took a .40 size SS bipe and scaled it to a Quadra 42 size.
I took the rated horsepower of the two engines:
40 - 0.7hp
Q42 - 3 hp.
The ratio is 3/0.7= 4.29
Then I took the cube root (3 dimesions to scale) = about 1.6
So I scaled the dimension by 1.6. It worked great. The bipe actually has better power/weight than the original.
Example: If you scale by 2, the plane will be twice as wide, twice as long and twice as high. So it should take 8 times the power to pull it. Do it the other way around, take the cube root of the power ratios and you get the ratio to scale each dimension.