Which equipment must aircraft have to operate in Class A airspace?

To operate in Class A airspace, aircraft are required to have specific avionics that ensure safety and effective communication among the air traffic control (ATC) system. The correct answer highlights the necessity for aircraft to be equipped with Automatic Dependent Surveillance–Broadcast (ADS-B) and Traffic Information Service–Broadcast (TIS-B).

ADS-B is a surveillance technology that allows aircraft to determine their position via satellite navigation and periodically broadcasts it, enabling ATC and other aircraft to receive real-time information about the aircraft's location, speed, and direction. This is critical in Class A airspace, where maintaining separation between aircraft is crucial due to the high density of traffic.

TIS-B complements ADS-B by providing additional information regarding nearby aircraft, which enhances situational awareness for the pilot. The combination of these technologies helps ensure compliance with the stringent operational requirements in Class A airspace, which is typically found at altitudes above 18,000 feet and is entirely controlled by ATC.

While radar and transponders are integral to air traffic management, their presence alone does not meet the specific requirements mandated for operating in Class A airspace. Similarly, VFR navigation equipment is not relevant to Class A airspace operations, which are exclusively conducted under Instrument Flight