The lift-to-drag ratio (L/D) at a 2 degree angle of attack is approximately equal to what angle of attack?

The lift-to-drag ratio (L/D) represents the efficiency of an aircraft's aerodynamics at a certain angle of attack. In this case, a 2-degree angle of attack generally corresponds to a condition where the plane is operating at a low angle for maximum efficiency. As the angle of attack increases, the lift-to-drag ratio typically improves until the optimal point at which the maximum L/D occurs.

At around 16.5 degrees of angle of attack, many airfoils reach their peak lift-to-drag ratio due to the balance achieved between lift generated and drag incurred. This peak is critical for pilots to understand, as exceeding this angle can lead to reduced performance and increased drag, ultimately affecting the aircraft's ability to maintain efficient flight. Thus, the value of approximately 16.5 degrees aligns well with the maximum lift-to-drag ratio, making it the correct answer in this context. Understanding this relationship is essential for pilots in optimizing their aircraft’s performance during various phases of flight.