This isn't about using GPS as the only navigation aid in an airplane. It's about augmenting the current air traffic system with additional, more accurate data t

This isn't about using GPS as the only navigation aid in an airplane. It's about augmenting the current air traffic system with additional, more accurate data to help manage airspace. ADS-B doesn't change anything about how a plane navigates. That's still done with a plethora of redundant instruments, all working together.