I have in front of me here a copy of the British Airways safety journal 'Flywise' dated November 1999. It contains an article on Communications Failures between Sept 1st 1998 and August 31st 1999 (12 months).
The article states there were a total of 207 reports of comms failure in that period on BA a/c alone!
OK, some of the incidents were not what I'd personally call true comms failures (e.g. ATC advising wrong handover frequency...easily cured by reverting to last freq), but many others were serious failures.
Interestingly ACARS was the cause of 18 'jamming' incidents, of which 6 were on the A320 fleet.
So it's not the remote occurence we'd like to think.
Excellent thread btw. Wouldn't it be great if the powers that be actually listened?
[This message has been edited by CaptSensible (edited 04 July 2001).]