How are runway numbers assigned?

• A. By the length of the runway.
• B. By nearest compass bearing in the direction of takeoff, rounded to the nearest 10 degrees.
• C. By the color of the runway markings.
• D. By the traffic volume on the airfield.

Answer: (B)

Runway numbers are based on the magnetic direction you would be heading when using that runway, expressed in tens of degrees. The direction is rounded to the nearest 10 degrees, and the number shown is that heading in tens (01 through 36). This means the same physical strip has two opposite numbers, separated by 180 degrees (for example, an east–west runway is Runway 09 on the east end and Runway 27 on the west end). The numbers are not about how long the runway is, its color markings, or how busy the field is.