The first link in the chain of an horrendous accident killing hundreds could well be that 50 minutes earlier Commander Boeing deselected 121.5 due to the incessant clamour of training fix requests (it was a hazy summer Saturday in the UK).
On Gin clear days you hear few Training Fix calls. On Hazy days you get loads and the reason is obviously NOT that everyone just decides to 'practice' talking to D&D - its because dozens of PPL's are Lost or Temporarily Unsure of Position or whatever euphenism you want to use. Rather than 'fess up they try to imply they are not actually unsure of anything but merely wish to practice an r/t procedure.
A GPS is now under £100 and would allow you to stop blocking what is a very important communication channel. I know you might only use it for 30 seconds and it sound quiet when you tune in. But honestly some days its an almost torrent of Practice Pans and Training Fixes. You Can't put up with it interfering with you actual r/t and so 121.5 gets deselected.
I wish for the CAA to conduct enquiries about how common this is and then I expect they will tackle the level of 121.5 useage in the UK FIR. You don't get it in other countries airspace. We are a little unusual in that respect.
Cheers
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