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Wouldn't it be cheaper to replace black boxes by telemetry?
Seems that the costs of a single search mission for an underwater black box exceeds the cost of installing and maintaining telemetry sytem in an entire fleet of aircraft plus ground stations.
By telemetry I mean a system that broadcasts all the information instead of recording it in the black box. In case of a crash the data would be immediately available.
Wouldn't such a method have shed light on such misteries as the missing Singapur Airlines flight?
Of course, in very extreme cases where the telemetry system fails before the crash the black box would still be available as a backup.