Interestingly real ATC radio comms has a nasty security problem as well: no authentication. As a broadcast medium, anyone can hop on the frequency and pretend to be ATC or a plane. No way to know who is the real one. You can take out your handheld radio right now and pretend to be JFK Tower or SF Approach.
Pilots are really good at pretending to be ATC because of training to handle CTAF MULTICOM UNICOM all of which is basically the same idea despite some paperwork differences. I guess CTAF is what it is, and the COMs are individual technical implementations. Its been a long time since student pilot days and I remember UNICOM had flight service stations and I don't think MULTICOM allows FSS chatter about fuel prices and car rentals or whatever on freq.
I live nearby and did student pilot training at an airport that doesn't have ATC staffing over 3rd shift. There was only perhaps one landing per hour overnight, so they don't staff the tower. Pilots just kinda broadcast off into space, listen to each other, and talk to each other.
I guess you'd describe it as a quiet party line rather than the formal meeting of staffed ATC communications.
Contrary to popular belief pilots listen constantly to each other and will get sorta-complaints from the tower if they haven't been paying attention to other pilots... Cessna 1234 do you have Cessna 6789 traffic in sight to your SW? And if you haven't been paying attention to the conversation between ATC and 6789 such that you don't know 6789 exists or is to your SW, then ATC is going to be kinda sorta pissed. This is why you can't replace ATC with a cellphone, at least not practically.
Another popular, weird, belief is ATC is like radio control and shutting down radio control makes all the planes fall out of the sky. Without the "meeting coordinator / committee chairperson" effect of the ATC, everything will happen in agonizing slow motion with massive distraction, but it'll all happen perfectly well. The reason ATC exists is it saves the pilots time, lets them focus on flying the plane a little more than focusing on commo with every other plane in the area. Its the cognitive difference between a hub-spoke topology and a full mesh. At 2am when there's only 0, 1, or 2 planes up in the airspace over the field, there's not much difference.
ATC does occasionally fail and there are procedures for load sharing.
One interesting EE problem is good luck talking over a 500 watt ATC tower at the field, from a couple miles away and 1 watt handheld. Just saying. Sure you can piss a lot of people off, but complete and utter long term takeover is going to be rather non-trivial. And there are a huge number of planes and sites with DF gear for tracking the old fashioned emergency beacons, so of all the things to jam, aircraft freqs are probably the one freq band likeliest to result in your demise ... You'll live a lot longer jamming the FM radio band or CB or the cops. Maybe not long, but longer.
