[Jeff_Brown]

Isn't radio an "old system" ripe for change? The cellular network accommodates millions of users in a space the size of Manhattan. Why do airplanes need to use a channel with such narrow throughput?

Also, voice uses far, far more bandwidth than text.

[p_l]

The simple system is reliable, has certain anti-locking behaviors, and doesn't depend on complex electronics while being obvious if jamming happens