What is the altitude range where a coded transponder with altitude reporting is required in controlled airspace?

The requirement for a coded transponder with altitude reporting in controlled airspace is defined by regulations that ensure maximum safety and traffic management. The correct choice specifies that transponders are required at and above 10,000 feet MSL, while explicitly excluding operations at and below 2,500 feet AGL.

This altitude regulation makes sense in terms of traffic density and safety protocols. Above 10,000 feet MSL, the airspace tends to be more congested with commercial air traffic, requiring detailed altitude reporting to better organize the flow of aircraft, reduce the likelihood of collisions, and ensure adherence to air traffic control requests. The exclusion of altitude reporting requirements at and below 2,500 feet AGL allows pilots to operate with more flexibility in lower altitudes, where different traffic patterns and types of operations are common, such as general aviation and approach to landing.

Understanding the specific parameters of transponder requirements helps pilots and air traffic controllers maintain necessary communication protocols and situational awareness in uniquely different environments of controlled airspace.