Wherever it belongs...
I fly on UAL quite a lot, and find that listening in to Ch.9 makes the journey a lot more enjoyable. It's interesting trying to understand the technical language starting from a position of ignorance, and when you do, you get more information about what's going on, than is announced on the PA. Since I'm someone who dislikes not being in control of my own destiny, I find this helpful in reducing the resulting frustration of long flights.
I'm sure that if any serious incident occurred, the pilot would usually just cut it off anyway, so the passengers would be none the wiser.
I realise that a lot of ATC professionals don't like the idea of "outsiders" listening in, but it's certainly given me a lot of respect for the job that ATC does.
And why is it that no UAL pilot can actually pronounce "BovingDon", it's always "BovingTon"
