Which term describes the peak lift coefficient of an airfoil?

Which term describes the peak lift coefficient of an airfoil?

• A. CL Max
• B. CL Min
• C. Lift Peak
• D. Max Lift Ratio

Answer: (A)

The peak lift coefficient is CL max. Lift coefficient (CL) measures how much lift the airfoil produces relative to the dynamic pressure and wing area, so it’s a convenient way to compare performance across speeds and sizes. As the angle of attack increases, CL grows until the air flow over the wing starts to separate, which is the onset of stall. At that point, lift stops increasing and actually falls, so the highest value CL reaches before separation is what we call CL max. This maximum depends on the airfoil shape, Reynolds number, surface finish, and thickness-to-chord ratio, which is why CL max isn’t a fixed number but a property of the specific wing and flow conditions. Other terms like CL Min, Lift Peak, or Max Lift Ratio aren’t standard ways to name this peak value, which is why CL max is the correct choice.

The peak lift coefficient is CL max. Lift coefficient (CL) measures how much lift the airfoil produces relative to the dynamic pressure and wing area, so it’s a convenient way to compare performance across speeds and sizes. As the angle of attack increases, CL grows until the air flow over the wing starts to separate, which is the onset of stall. At that point, lift stops increasing and actually falls, so the highest value CL reaches before separation is what we call CL max. This maximum depends on the airfoil shape, Reynolds number, surface finish, and thickness-to-chord ratio, which is why CL max isn’t a fixed number but a property of the specific wing and flow conditions. Other terms like CL Min, Lift Peak, or Max Lift Ratio aren’t standard ways to name this peak value, which is why CL max is the correct choice.