One precedent for this is FLARM, the air traffic system designed by glider pilots in Europe. It was one of the first systems deployed where aircraft had GPS equ

One precedent for this is FLARM, the air traffic system designed by glider pilots in Europe. It was one of the first systems deployed where aircraft had GPS equipment broadcasting their positions to each other. Developed privately and first deployed voluntarily. https://en.wikipedia.org/wiki/FLARM https://en.wikipedia.org/wiki/FLARM