Having read through 10 pages of this stuff, I am amazed at some of the 'tosh' being presented. Look at the facts:
The UK has filed a difference with ICAO regarding the use of 121.5. This was not done as a whim.
Nobody ever had a problem until the world started to get twitchy about being shot down. All of a sudden the airliners start monitoring 121.5.
The airline pilots' associations, quite within their rights, made representations to the Regulator (the CAA) about excessive, practice, transmissions from GA pilots on 121.5. The Regulator initiated a fact finding exercise.
Results, collated by D&D demonstrated that by far the most significant amount of use of 121.5 was by airliners who had either checked in on the wrong freq, chose to chat to each other or kept shouting "On Guard".
Now let us speculate:
The risk of being shot down because someone is not monitoring 121.5 is minimal.
If you are on a busy, or even medium intensity, ATC freq then there is no need to monitor Guard. Turn it down. IMHO that you only need to listen-out if things are spookily quiet.
Most professionals in aviation can adeptly manage two or more radio freqs at once. That is why each radio has a volume control.
The CAA will continue to monitor and, if necessary, change UK policy. After all, considering their risk averse nature, they would not want to be party to a flight safety incident.
As long as there are idiots who chose to use Guard for reasons other than those promulgated in National AIPs (including those of other countries), there is no case against sanctioned procedures.
An exchange heard on 121.5 yesterday:
London Centre is broadcasting details of a TDA around a specific incident.
German pilot "You are on Guard"
Other pilot "She is broadcasting an an emergency message, you silly man!"
Last edited by London Mil; 6th June 2006 at 16:01.