The lift and drag coefficients of a symmetric airfoil are related to its aspect ratio (A,)...

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The lift and drag coefficients of a symmetric airfoil are related to its aspect ratio (A,) by the following approximate formula: CL 2m sin(a) CD= CD + (A) a= Angle of attack CD-= drag coefficient of the infinite-span airfoil. A,= aspect ratio (L/C) L = airfoil length C= airfoil chord W = Weight of aircraft A = Lifting surface CLmax=Maximum lift coefficient p = Medium density 2W V = (max PA Because the lift coefficient for any airfoil is limited to a maximum value (CLmax), which depends on the airfoil geometry, there is a minimum speed, or stall speed, for the aircraft at which the induced lift just supports the weight of the aircraft. This minimum, or stall, speed is given by: (3) (1) /2 (2) The lift and drag coefficients of a symmetric airfoil are related to its aspect ratio (A,) by the following approximate formula: CL 2m sin(a) CD= CD + (A) a= Angle of attack CD-= drag coefficient of the infinite-span airfoil. A,= aspect ratio (L/C) L = airfoil length C= airfoil chord W = Weight of aircraft A = Lifting surface CLmax=Maximum lift coefficient p = Medium density 2W V = (max PA Because the lift coefficient for any airfoil is limited to a maximum value (CLmax), which depends on the airfoil geometry, there is a minimum speed, or stall speed, for the aircraft at which the induced lift just supports the weight of the aircraft. This minimum, or stall, speed is given by: (3) (1) /2 (2)