The lateral dimensions of Class D airspace are based on which factor?

• A. The instrument procedures for which the controlled airspace is established
• B. The number of runways
• C. The airport traffic density
• D. The type of navigation aids used

Answer: (A)

Lateral dimensions of Class D airspace are defined to contain the instrument approach procedures for that airport. This means the boundaries are drawn to enclose the published instrument approach paths—initial, intermediate, and final segments, plus any missed-approach routing—so IFR traffic remains within controlled airspace from the surface up to the designated ceiling. The vertical extent is typically from the surface to about 2,500 feet above the airport elevation, though the exact shape can be irregular to fit the approach procedures. The size isn’t determined by how many runways the airport has, how busy it is, or the type of navigation aids used; those factors don’t set the boundary—the instrument procedures do.