What is aircraft Angle of Incidence?
The angle of incidence is the angle formed by the longitudinal axis of the airplane and the chord of the wing. The longitudinal axis (also the “roll axis”) is an imaginary line that extends lengthwise trough the fuselage from nose to tail. The angle of incidence is measured by the angle at which the wing is attached to the fuselage. The angle of incidence is fixed – it normally cannot be changed by the pilot.
In any of several scientific and engineering disciplines, the term angle of incidence is used as a measure of deviation from “straight on”, for example in the approach of a ray to a surface, or the direction of an airfoil with respect to the direction of an airplane.
In aviation, it refers to the angle between the wing’s chord and the longitudinal axis of an aircraft (a fixed value). The wings are typically mounted at a small positive angle of incidence, to allow the fuselage to be “flat” to the airflow in normal cruising flight. Angles of incidence about 6° are common on most general aviation designs.
Another term for angle of incidence in this context is “rigging angle.” It should not be confused with angle of attack, which is the angle the wing chord presents to the airflow in flight.
