Which airspace requires ATC authorization for operation?

Class B airspace requires ATC authorization for operation. This airspace surrounds major airports and is designed to ensure a safe environment for the high volume of aircraft that operate in and out of these locations. In Class B airspace, all pilots must obtain clearance from Air Traffic Control before entering. This requirement is in place to manage the significant traffic density and to coordinate the movements of both commercial and general aviation flights within the vicinity of busy airports.

While other types of airspace, such as Class A, also require ATC authorization, Class B is unique in its stringent requirements relating specifically to entry and operations, ensuring safety in areas of high pilot and passenger activity. Classes G and E do not require ATC authorization for general operations, which distinguishes Class B's strict access protocols.