What is the name of the 30 nautical mile ring around Class B airspace that requires a transponder to transition in?

What is the name of the 30 nautical mile ring around Class B airspace that requires a transponder to transition in?

• A. Mode C veil
• B. Outer ring
• C. Transition area
• D. Terminal area

Answer: (A)

Mode C veil is the name for the 30 nautical mile ring around Class B airspace. This ring exists so ATC can see the altitude of every aircraft entering or operating near the Class B boundary. Because of that, any aircraft transitioning into the Class B within that ring must have an operable transponder with altitude reporting (Mode C) turned on. The other terms aren’t the standard label for this ring—the outer ring and terminal area refer to other parts or concepts of Class B airspace, and “transition area” is not the term used for this 30 NM ring.

Mode C veil is the name for the 30 nautical mile ring around Class B airspace. This ring exists so ATC can see the altitude of every aircraft entering or operating near the Class B boundary. Because of that, any aircraft transitioning into the Class B within that ring must have an operable transponder with altitude reporting (Mode C) turned on. The other terms aren’t the standard label for this ring—the outer ring and terminal area refer to other parts or concepts of Class B airspace, and “transition area” is not the term used for this 30 NM ring.