An Australian official says a search crew hunting for the missing Malaysia jet. Has located a new possible underwater signal the search agency coordinating the search off Australia's West Coast. Says an Australian navy aircraft picked up the signal today in the same area that a ship heard sounds consistent with the aircraft's black boxes earlier this week. CBS news transportation safety analyst mark -- car is with us on the WB Ian lifeline. Marcus former chairman of the National Transportation Safety Board good morning mark. Well at least these signals are they getting fainter but they're so vital in getting to narrow the field down today. They certainly -- -- this is an important piece of data that we need to continue to do the triangulation. And thereby do that. The focus -- much now hours search zone so that we can unused who -- the and 21. That is the unmanned submersible which will go down and look at -- -- dead. Through -- that -- and -- stand around dark and actually begin to do graphic images if you will of what they may lead out there. -- in fact they can find something. They will then come back up reconfigure that battle and send it back down to actually have a few high definition pictures. If flight 370. Is at the bottom of the Indian Ocean in that area mark. And it is in an area where it could possibly be miles underwater. And under incredible pressures at those -- What could that pressure had dawned on that aircraft. It is certainly -- seeing a what what high pressure does to other. Actually it's -- When you believe that we will still be able to get the boxes up. And duly appropriate data readout of and then find out why that happened in the aircraft itself. The question will be he would do it will be able to do any recovery of the victims of that to -- department. No humans can go to that -- -- right. No humans can go to the -- -- president. Coming in these remarkable that there aren't capable of literally grabbing things and bringing them out that's what they're going to do. As soon as they have some photographs and some side to side against the Iraq. All he had debris site they won't have another device that will come down. And act -- as up arms that are not only able to articulate and grab things they will be able to pick up things perhaps put it in another box that they carry that. Would be able to bring it back up to the circus. Marc we're here about the flight data recorders. Days re circulated reactivated other words they. Begin recording over data that was from. Of the black box previously because the plane goes in the air supposedly in reportedly for so many hours after disappeared. Is it possible that some vital information. Those data recorder is -- lost. Well we're looking at the cockpit voice recorder that say to our -- the content is continuously doesn't re record over itself. The flight data recorder on the other hand. Is basically built to do 25 hours of data some some -- actually do more than that though we're convinced that if in fact. The -- is survived you know in back to the whoever was in the cockpit potentially. Did not turn off. And the circuit breakers to the boxes. We will get some data that's going to be helpful to. This investigation. Marquardt Reggie could join us for the update thank you. That's mark -- car CBS news transportation safety analyst and former chairman of the NTSB.