What airfoil angle of attack setting is required to produce zero net lift on a positively cambered airfoil?

To achieve zero net lift on a positively cambered airfoil, a negative angle of attack is required. A positively cambered airfoil generates lift as airflow moves over it, typically producing lift at a positive angle of attack. However, when the angle of attack is set to a negative value, it effectively alters the airflow over the airfoil in such a way that the lift force can be reduced to zero.

In this scenario, the airflow direction leads to a reduction in the pressure differential needed to create lift. Thus, the negative angle of attack counteracts the natural lift tendency of the positively cambered design until the net lift equals zero. This principle is essential in understanding how angle of attack affects lift generation in various airfoil designs.

Maintaining a zero angle of attack typically does not yield zero lift with a positively cambered airfoil, as it usually results in a positive lift being produced. A positive angle of attack, conversely, enhances lift rather than diminishing it, particularly with an airfoil designed to be cambered positively. Therefore, it's the negative angle of attack that specifically cuts lift down to a neutral state.