Mearns, who is not involved in the effort but knows people who are and has been through the process himself, said he believes Angus Houston, the retired Australian air chief marshal heading the Joint Agency Coordination Center, is deliberately awaiting incontrovertible visual evidence out of respect for the passengers' families.Fox hype. All based on one man's opinion.
If they locate a solid signal, I'd be pissed off big-time if I were a surviving family member that they held onto that until they got 'visual'. The guy's just using Fox as well for free publicity, albeit pissing off the entirety of the families doing so.
They're supposedly using the Towed ROV Artemis for this part of the search. Once they've completed a pattern they should be able to pinpoint the source.
If I were a family member, that would be good enough for me (and the least I'd want to know).
The search team needs to triangulate the signal with a certain degree of confidence that they indeed have directional bearings. They can only do this by measuring amplitude of the signal i.e if the signal strength is growing stronger, they are moving closer.
That in itself is not exact because they could be on a tangent source to the signal. I'm sure the triangulation is exactly what they are doing as I write this.