On a sectional chart, airspace class is often indicated by color and line style. Which symbol indicates Class B airspace?
AA solid blue line bounding concentric sectors✓
BA solid magenta line bounding a single circle
CA dashed blue line bounding the outer boundary
Why →Class B airspace is depicted on sectional charts with solid blue lines that outline the class's characteristic concentric shelf structure around major airports. Each shelf shows the floor and ceiling as a pair of numbers (e.g., 100/SFC means 10,000 feet to surface).
The trap →Solid magenta is Class C and dashed blue is Class D. Confusing Class B shelves with Class C rings is a common sectional-reading error; the concentric shelf structure plus solid blue is the Class B signature.
Field note →Class B looks like an upside-down wedding cake on the sectional because each shelf's floor rises as you move outward from the primary airport.
SOURCE → FAA Aeronautical Chart User's Guide, Airspace ClassificationsCHECKED JUL 16ACS II.A.K1EASY