Position determination of an aircraft on the airport may be determined visually by the controller, by pilots, or through the use of ___.

• A. ASDE (Airport Surface Detection Equipment)
• B. GPS
• C. Radar
• D. VOR

Answer: (A)

On the airport surface, position can be determined by visual observation, pilot reports, or through the use of Airport Surface Detection Equipment. ASDE is a ground surveillance system that uses radar to monitor and display the exact locations of aircraft and ground vehicles on taxiways and runways. This specialized tool gives controllers a precise picture of movements on the apron and ramps, helping prevent conflicts and runway incursions, especially in poor visibility.

GPS provides global positioning via satellites, but it isn’t the standard means used by ATC to determine where aircraft sit on the field. VOR is an en-route/navigation aid, not a surface-positioning tool. Radar is a general term for surveillance, but ASDE specifically targets the airport surface, offering the most direct and reliable surface position information.