The ratio of the surface area of Wilbur’s plane to the surface area of Orville’s plane is the square of the scale factor of Wilbur’s mini replica of Orville’s plane. Since Wilbur’s mini replica has linear dimensions that are 12 the size of Orville’s model airplane, it follows that the ratio between the lift forces on Wilbur’s and Orville’s planes is 12×12=14

The ratio of the surface area of Wilbur’s plane to the surface area of Orville’s plane is the square of the scale factor of Wilbur’s mini replica of Orville’s plane. Since Wilbur’s mini replica has linear dimensions that are \(\dfrac{1}{2}\) the size of Orville’s model airplane, it follows that the ratio between the lift forces on Wilbur’s and Orville’s planes is \(\dfrac{1}{2}\times\dfrac{1}{2}=\dfrac{1}{4}\)