[teovall]

The antiquated AM mode and the lack of encryption or even digital encoding is a safety feature for air traffic voice communications. Very weak signals still have a chance of being intelligible and if two signals are transmitted at once on the same frequency, both can still be heard.

[H8crilA]

Yeah but it's terrible for security. Also digital modes work just fine at the same range - I have no problem hearing ADS-B messages from up to 200mi away from my ground level antenna, where the max range is only limited by the curvature of the planet.

And note that the real problem is with authentication (MACs, or digital signatures), not encryption. Public availability of those records is actually probably beneficial. It's a common misconception to think that you need to encrypt while in reality you perhaps need to encrypt, but first you absolutely must authenticate.

[tjohns]

You don't really need more security, because if a pilot gets an ATC instruction that doesn't make sense, they're going to question it. Pilots aren't following instructions blindly, everything is mentally cross-checked against what we expect should be happening for situational awareness. (And ATC would also hear the interloper and immediately speak up.)

On top of that, almost everyone in the US also has some form of collision avoidance technology now, as well (either TCAS or ADS-B).

And there's plenty of times where the only time I could hear ATC was with the squelch full open, trying to pick a faint signal out through the static. Digital modes are terrible for this.

[ryandrake]

Is this an actual problem that is happening in practice, though? How many instances of "unauthenticated" airband communication have caused an accident? I don't know. Even if the answer is nonzero, I'd be willing to bet it's less than ten in decades.