It's already set in motion: https://en.wikipedia.org/wiki/Automatic_dependent_surveillance_%E2%80%93_broadcast#ADS-B_Out_satellite_reception https://en.wikipedi

It's already set in motion: https://en.wikipedia.org/wiki/Automatic_dependent_surveillance_%E2%80%93_broadcast#ADS-B_Out_satellite_reception https://en.wikipedia.org/wiki/Automatic_dependent_surveillan... It wouldn't require any extra ADS-B hardware on the planes other than sky-facing antennas.