What is the chord of a wing?

Definition: the chord is the line stretching from the leading edge of the wing to the trailing edge parallel to the centerline. The chord of a wing, stabilizer, and propeller is determined by measuring the distance between the leading and trailing edges in the direction of the airflow.

FS = Fuselage stations (Fus. Sta. or FS) are numbered in inches from a reference or zero point known as the reference datum. The reference datum is an imaginary vertical plane at or near the nose of the aircraft from which all fore and aft distances are measured. The distance to a given point is measured in inches parallel to a centerline extending through the aircraft from the nose through the center of the tail cone. Some manufacturers may call the fuselage station a body station, abbreviated BS.

BL = Buttock line or butt line (BL) is a vertical reference plane down the center of the aircraft from which measurements left or right can be made.

WL = Waterline (WL) is the measurement of height in inches perpendicular from a horizontal plane usually located at the ground, cabin floor, or some other easily referenced location.

AS = Aileron station (AS) is measured outboard from, and parallel to, the inboard edge of the aileron, perpendicular to the rear beam of the wing.

KS = Flap station (KS) is measured perpendicular to the rear beam of the wing and parallel to, and outboard from, the inboard edge of the flap.

NC = Nacelle station (NC or Nac. Sta.) is measured either forward of or behind the front spar of the wing and perpendicular to a designated water line.