How to start CPDLC?
I'm not a pilot but I enjoy listening on liveatc.net.
Here I have a question on how to start CPDLC, switching from voice communication.
Once an aircraft enters CPDLC area, like Pacific Ocean, does controller tell pilots "Contact XXX center on CPDLC"?
Are pilots assigned HF frequency for backup voice communication?
Then how do they end CPDLC as an aircraft comes close to the the end of the ocean?
I hope some answer my question here.
Thank you.