What minimum radio equipment is required for VFR operation within Class B airspace?

• A. Two-way radio communications equipment, a 4096 code transponder, and an encoding altimeter
• B. Transmit-only radio, no transponder
• C. Mode S transponder only
• D. ADS-B Out only

Answer: (A)

In Class B airspace, ATC needs to be able to talk to you and to know exactly where you are and how high you’re flying. That requires two things: a radio that you can both transmit and receive on, and a transponder that can identify your aircraft and report your altitude to ATC. The minimum described—two-way radio communications gear plus a transponder that can provide a discrete squawk code (4096 codes) and encode altitude—meets both needs: you can hear and respond to ATC, and ATC can identify you on radar and know your altitude for proper separation.

The other options fall short because one by itself doesn’t give ATC two-way contact, or it relies on equipment that doesn’t guarantee you can both communicate and report altitude. While ADS-B Out is increasingly required in many operations, the combination here specifically satisfies the essential contact and altitude-reporting capability ATC relies on inside Class B.