I should have said to generate lift in level flight. Drop anything with air resistance and it’s technically generating lift. However it’s important to separate the angle of attack relative to the airstream vs angle of attack relative to the ground for falling objects.
Anyway non-semmetric airfoils are about efficiency when the aircraft never flies upside down. Unfortunately you occasionally see mislabeled diagrams where the angel of attack seems to be zero when the wing is laying flat rather than the leading and trailing edge being level which creates a great deal of confusion.
Anyway non-semmetric airfoils are about efficiency when the aircraft never flies upside down. Unfortunately you occasionally see mislabeled diagrams where the angel of attack seems to be zero when the wing is laying flat rather than the leading and trailing edge being level which creates a great deal of confusion.
PS: A frisbee shape is largely a question of grip as rings can fly further, but they both need positive angel of attack to achieve significant distances. https://web.mit.edu/womens-ult/www/smite/frisbee_physics.pdf