How is the configuration of Class B airspace typically described?

The configuration of Class B airspace is typically described as an upside-down wedding cake. This characterization accurately reflects how Class B airspace is structured in layers, with each layer representing a different altitude range. The concept is intuitive because the airspace is designed to provide increasing vertical separation for aircraft as they approach the airport, much like the tiers of a wedding cake.

The lower tier is closest to the airport and extends upward, while the upper tiers encompass larger horizontal areas. This tiered structure helps manage the traffic density and ensures safe separation between different aircraft operations, particularly in busy metropolitan areas where Class B airspace is often found. Each layer of the "cake" has specific altitude restrictions and requirements, forming a controlled airspace where permissions for entry differ based on the altitude and approach to the airport.

This unique configuration is essential for efficient air traffic management within busy airspace environments, facilitating organized entry and exit from major airports while providing adequate separation between aircraft at various levels.