FAA Ground School Practice Test

To operate within 30 miles of a Class B primary airport, it is mandatory for all aircraft flying from the surface up to 10,000 feet MSL to have an operable transponder equipped with either Mode S or 4096-code capability. This requirement is in place to enhance air traffic control's ability to track aircraft and ensure safe separation between them, particularly in busy airspace around Class B airports.

Having a Mode S or 4096-code transponder allows for better identification and provides altitude reporting, which is vital for maintaining safety and managing air traffic in areas that may experience high volumes of aircraft operations. This capability helps controllers maintain awareness of the aircraft's position and altitude, thus reducing the risk of mid-air collisions and improving overall situational awareness.

The other options do not meet the necessary requirements for operating in this critical airspace. An operable transponder without altitude reporting does not provide the level of safety needed, nor does basic VFR transponder capability suffice in such busy environments. Similarly, asserting that no specific equipment is required contradicts the established regulations governing Class B airspace.