I appreciate that sweeping changes (dual FDRs, et cetera) would prolly be cost prohibitive.
But what about a simple kit for frames dedicated to long-haul overwater flights?
I would think that a very basic "paste on" unit that would sense immersion in salt water and self-detach from the fuse (or wherever) would be enough.
If it were a flatish thing which didn't affect aerodynamics, there wouldn't need to be a whole lot of recert activity.
It could then float, ping, and access the same satellites that ships' beacons use, albeit with a different code.
That would at least give an initial clue as to where to look.
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