What is the angle between the longitudinal axis and the chordline?

The angle between the longitudinal axis of an aircraft and the chord line of a wing is known as the angle of incidence. This angle is significant because it is a fixed angle set during the design and construction of the aircraft. The angle of incidence affects the airflow over the wing and, therefore, plays a critical role in determining the lift characteristics of the aircraft during various phases of flight.

In contrast to this, the angle of attack refers to the angle between the chord line of the wing and the relative wind or airflow. Pitch attitude indicates the orientation of the aircraft's nose relative to the horizon and is not a direct measure of the relationship between the wing's chord line and the longitudinal axis. Wing area, while important for lift calculations and performance estimates, is simply a measure of the surface area of the wings and does not pertain to angular relationships. Thus, angle of incidence is the appropriate term for the angle described in the question.