Class B is an International Civil Aviation Organization (ICAO) air space designation that protects the approach and departure paths from aircraft not under air traffic control. All aircraft inside Class B airspace are subject to air traffic control. Traffic operating under VFR must be identified on radar and explicitly cleared into the airspace before they can enter. The airspace is commonly depicted as resembling an "upside-down wedding cake." The inner most ring extends from the surface area around the airport to typically 10,000' MSL. Several outer rings usually surround it with progressively higher floors to allow traffic into nearby airports without entering the primary airport's Class B.

United States

The airspace around the busiest US airports is classified as ICAO Class B. The following airports in the United States are Class B:

(listed by state and IATA Airport Code ICAO Airport Code)

Arizona:

• PHX/KPHX Phoenix Sky Harbor International

California:

• LAX/KLAX Los Angeles International
• NKX/KNKX Miramar Marine Corps Air Station
• SAN/KSAN San Diego International Lindbergh Field
• SFO/KSFO San Francisco International

Colorado:

• DEN/KDEN Denver International

Florida:

• MIA/KMIA Miami International
• MCO/KMCO Orlando International
• TPA/KTPA Tampa International

Georgia:

• ATL/KATL Hartsfield-Jackson Atlanta International

Hawaii:

• HNL/PHNL Honolulu International

Illinois:

• ORD/KORD Chicago O'Hare International

Kentucky:

• CVG/KCVG Cincinnati/Northern Kentucky International

Louisiana:

• MSY/KMSY Louis Armstrong New Orleans International

Maryland:

• ADW/KADW Andrews Air Force Base
• BWI/KBWI Baltimore/Washington International

Massachusetts:

• BOS/KBOS General Edward Lawrence Logan International (Boston)

Michigan:

• DTW/KDTW Detroit Metropolitan Wayne County

Minnesota:

• MSP/KMSP Minneapolis-St. Paul International/Wold-Chamberlain

Missouri:

• MCI/KMCI Kansas City International
• STL/KSTL Lambert-St. Louis International

Nevada:

• LAS/KLAS Las Vegas McCarran International
• LSV/KLSV Nellis Air Force Base

New Jersey:

• EWR/KEWR Newark Liberty International

New York:

• JFK/KJFK John F. Kennedy International
• LGA/KLGA New York La Guardia

North Carolina:

• CLT/KCLT Charlotte/Douglas International

Ohio:

• CLE/KCLE Cleveland-Hopkins International
• CVG/KCVG Cincinnati/Northern Kentucky International Airport

Pennsylvania:

• PHL/KPHL Philadelphia International
• PIT/KPIT Pittsburgh International

Tennessee:

• MEM/KMEM Memphis International

Texas:

• DAL/KDAL Dallas Love Field
• DFW/KDFW Dallas-Fort Worth International
• HOU/KHOU Houston William P. Hobby
• IAH/KIAH George Bush Intercontinental (Houston)

Utah:

• SLC/KSLC Salt Lake City International

Virginia:

• DCA/KDCA Ronald Reagan Washington National
• IAD/KIAD Washington Dulles International

Washington:

• SEA/KSEA Seattle-Tacoma International