He's technically correct however like a lot of laws on the statute books, it would be very unlikely to pass the public interest test for prosecution which is why Police don't blink at the thousands of scanners they see at airshows and why planefinder and flightradar apps are not illegal.
In fact given that you can listen in on ATC on some airlines own flight entertainment, AND our on society is much more open than the post war one which passed the act, it's passing into irrelevance over time.
Last edited by Skipness One Echo; 7th May 2013 at 07:32.