Class B airspace limits are charted primarily in altitude measured as

• A.feet AGL above the pilot's location
• B.feet MSL
• C.flight levels below 18,000 feet

Why

Class B floors and ceilings on the chart are given in feet MSL, which is why a pilot must account for local ground elevation. Flight levels are used at and above 18,000 feet MSL in Class A.

Source: FAA-G-8082-22 Ch. 2 · ACS knowledge area: Airspace Classification and Operating Requirements · From the Airspace & Flight Restrictions practice bank (AIR-058).

Practice this category as a full test

More Altitude References questions

• What are the vertical limits of Class A airspace?
• Under Part 107, how may a remote pilot operate a small unmanned aircraft in Class A airspace?
• Class B airspace generally extends from the surface up to what altitude?
• On a sectional chart, how is Class B airspace depicted?
• A remote pilot wants to fly within Class B airspace at an altitude shown on the UAS Facility Map. What is required before the flight?