This article confirms that the USA are already testing satellites to track aircraft as a replacement for AWACS. Question is which are the satellites? Likely not the NRO or SDA missions. Unlikely also GEO sats and small sats. (1/2) aviationweek.com/defense/airc...
aviationweek.comRise Of Space-Based Aircraft Tracking Spells Threat To USAF E-7As | Aviation Week NetworkA top U.S. military official confirmed that satellites are demonstrating aircraft tracking as the E-7A program faces a cancellation threat from the Pentagon.