Which factor does NOT affect the angle of incidence of an airplane?

The angle of incidence refers to the angle between the chord line of the wing and the horizontal plane, typically established during the design and assembly of the aircraft. Various factors influence this angle and how the aircraft performs, but air pressure specifically does not affect the angle of incidence.

The factors that do influence the angle of incidence include aircraft configuration, which involves how the aircraft is set up (such as the arrangement of wings, fuselage, and tail), and weight distribution, which can change the aircraft's balance and attitude in flight. The position of control surfaces, such as ailerons and elevators, can also impact the effective angle of attack, which is closely related but distinct from the angle of incidence.

In contrast, air pressure affects lift and drag by influencing the air density and flow over the wings, but it does not physically change the angle of incidence itself, which is a fixed characteristic set during the design phase of the aircraft. Thus, air pressure is not a determining factor in adjusting or affecting the angle of incidence.