My view lies with those who believe 121.5 should be reserved for genuine emergencies or loss of communication. If training is required it should be performed by simulation or if transmission is really required, on a quiet frequency.
CAT around the world monitors 121.5 on the 2nd box to aid those in distress and to provide a secondary communication channel if Box 1 is on the wrong frequency. This works well all over the world apart from the area from 15W to 5E and 50N to 55N. Here the NAA has declared to ICAO that 121.5 will be used for practice emergencies because a legacy triangulation system left over from the 1950s is used to provide a rough fix. Technology now offers many more effective solutions to lost aircraft.
The problem is that CAT at FL300+ in the said area is obliged to deselect 121.5 owing to the continuous practice traffic on that frequency which interfers with listening on the primary frequency. This leads to there being no secondary method of communication when primary communication is lost. This has already led to CAT being intercepted and escorted when availablity of 121.5 could have avoided this event.
I understand that with a certain high profile event being expected in 2012, the NAA will look again at maintaining a quiet 121.5, free of training fixes, and fully available as a loss of communication first stop.
Last edited by topoverhaul; 29th Aug 2010 at 08:33.