How is Class B airspace defined?

Class B airspace is defined as a specific type of controlled airspace designed to manage the operations of aircraft around busy airports. It typically extends from the surface up to a specified altitude, which varies by location, but it is generally structured to accommodate large aircraft and to provide a higher level of safety and efficiency for air traffic.

The correct definition of Class B airspace encompasses the controlled airspace that includes sectors at lower altitudes, particularly around major airports where density of air traffic is high. This airspace helps in providing a clear boundary where the air traffic control (ATC) can manage the operations of both departing and arriving aircraft as well as surrounding traffic.

In the scenario provided, the uniqueness of Class B airspace requires it to manage air traffic at lower altitudes specifically, along with an associated minimum altitude, typically defined at or above 12,500 feet ASL in some regions. This places a significant emphasis on managing traffic effectively in areas with substantial air operations.

The distinctions in the other options highlight other classifications of airspace but do not accurately capture the essence of Class B airspace’s focus on controlled environments around critical regions, which is essential for maintaining safety and efficiency in the busy skies over major airports.