Starting January 1, 2020, you must be equipped with ADS-B Out to fly in most controlled airspace:
Any airspace that requires the use of a Transponder today will on January 01, 2020 also require aircraft to be equipped with a Version 2 ADS-B Out system. This can be either a 1090ES (DO-260B) ADS-B system or a UAT (DO-282B) ADS-B system.
For aircraft operating above FL180 (18,000 ft.) or to comply with ADS-B mandates outside the United States, you must be equipped with a Mode-S transponder-based ADS-B transmitter. For aircraft operating below 18,000 ft. and within the United States ADS-B rule airspace, you must be equipped with either a Mode-S transponder-based ADS-B transmitter or with UAT equipment.
Download the Equip ADS-B Google Earth map (KMZ) to look at the location of ADS-B rule airspace at your home base and where you fly. Pan and zoom to different locations and turn on the various capabilities the map includes:
• 3-dimensional depictions of rule airspace and airports
• Overlays of ADS-B surveillance coverage — airspace where ATC can see aircraft transmitting ADS-B Out information at altitudes of 500′, 1,500′, 3,000′, 5,000′ and 10,000′ AGL
Need help? Watch the Google Earth Demo video and take a look at the instructions (PDF) for how to download and view the Equip ADS-B Google Earth map.