still, authorities caution there is a long way to go. australia's top air accident investigator now saying the cost of a prolonged search could reach a quarter of a billion dollars if more private equipment is needed. miguel marquez joins us from perth with the latest. good morning, miguel. >> reporter: good morning there, carol. those discussions will be happening between all the countries involved. there is no indication that any country wants to give up this search. in fact, they are doubling down on it. the blue fin going down, we believe, for its fourth dive now to search for another 16 hours and then do another data dump. all of those resources are still up on the ocean. the ships on the surface of the ocean responding to what the pos ioedon see from the air and the p-3s what they see from the air. those ships can be directed anything they see on the ocean surface. a very big load of families that the oil was found not to be that