Analysis 2- Number of Wings with Given Airfoil

The requirement was to find an airfoil and number of wings that did not exceed 40 g’s of instantaneous force when hitting the ground. The wing could be no longer then 20 inches so about 10 inches of usable wing with a thickness of 4 inches being the maximum and weight of 10 pounds. A high lift air foil with low angle needed was determined (FX74-CL5-140). Using the properties of the airfoil the terminal velocity was found, then using that and the air resistance formula the area was determined. The area was then used to find that 6 blades will be minimum to succeed in 40 g's of instantaneous force on impact.