ELT's are fine in theory, and psychologically comforting, but frankly the evidence overwhelming that they don't go off reliably in a crash.
That's why my practised SOP is to turn it on
before the crash. Even a few seconds of transmission on 121.5 and 406 before the damage in the crash may be enough alert rescue authorities and provide location information.
I might add that despite knowing this, we installed a 406 MHz ELT as part of our ADS-B upgrade.
A very good idea, in my opinion.
If your aircraft still has an old 121.5 ELT, its batteries by now are very suspect.
And you are, in my opinion, stupid and Charles Darwin will have you in his sights, if you think an old 121.5 ELT with timex batteries is an effective risk mitigation strategy.
And beacon broadcasts on 121.5 are very difficult to locate. 121.5 has very marginal benefit for beacon transmission. If you don't have a 406 MHz ELT with GPS interlink, you're better off with an EPIRB.
If you don't have a 406 MHZ ELT or PLB or EPIRB with GPS 'interlink' you are, in my opinion, stupid and Charles Darwin will have you in his sights.
Which brings us to a PLB or EPIRB. Where is yours? In the bottom of a flight bag?
If it's in the bottom of your flight bag, you are, in my opinion, stupid and Charles Darwin will have you in his sights.
When will you trigger it? In flight, will you have time or be busy flying the aircraft and dealing with the emergency?
Mine's on my hip and I practice activating it in the air. Less than 3 seconds.
On the ground, will you be conscious? Do your passengers know how to set it off? Have you briefed them? Do they know where to find it?
All of which points up the prudence, in my opinion, of activating all ELTs, PLBs and EPIRBs in the air, having practised doing it.
Frankly, I think the logic is inescapable that you should be monitoring 121.5 and that using it for an emergency call should be part of your emergency protocol
And frankly, so far as I can tell, you've not explained the disadvantages of broadcasting a MAYDAY on Area.
If the assumption is that people are flying around with old 121.5 ELTs with time expired batteries, and a PLB in the bottom of a flight bag that's inaccessible and impractical to activate because no one has practised or been briefed on the process, I agree absolutely: Those people should cry for help long and hard on 121.5.
But please don't assume everyone's that stupid.