The D&D repport is slightly misleading us all by stating that practice PANS take up only 1% of AIR TIME, whereas 75% of CALLS are mistakes by commercial pilots. This is comparing apples with oranges. Why?
This is how a tippical commercial pilot sounds on 121.5
com pilot 1:Maintanance good day, it's the XXX215.
com pilot 2: You are on GUAAAAAAARD
com pilot 1: ...
or
controller: XXX215, if you hear me call London on 129.000
Very simple stuff, easily filtered out of your mind.
Now the practice pan.
student: uuuhhh..Pra...uhhh, PPPractice PAN, P-ractice PAN, PRACTice PAN!
......GOLF....
ALFA
.....CH...uuuh...BRAVO...
DELTA,
.....
CHARLIE
...............................from BLABLABLABLABLA, YEPYEP uuuhh....to YEPYEPYEP, BLABLAYEP...uuhhh.. Cessnah Etcetera, etcetera. Temporary unawhere of my position
This stuff is pervasive, even with the best selective attention you cannot filter this out! So by this time every single pilot is poking at the volume knobs or even deselecting 121.500 completely. And the controller hasn't even begun to speak yet.
So, yes, it may well be just 1% of AIR TIME, but a very distracting one at that.
And to be clear, I am honestly not trying to make fun of student pilots. All commercial pilots have been there at some point in their life. But it is only in the UK where PANS are being practiced live for everyone to hear. Why not put more effort into an afternoon lesson in basic VOR fixes?