planes just finished coming in for the night. they re still trying to spot the piece of debris on the surface. paula newton, thank you so much. in perth at 2:00 your time. let s focus on the underwater pings. the precious ping sound happened about once every second. but back to the battery. battery-powered ping may soon go silent. let s bring in mike williamson. nice to have you on. thank you. we re talking about this approximately 150-mile track to use this pinger locater. listening for the click, click, too ultimately locate the black boxes. but my question, is covering that kind of surf zone doable in the two days they have before the battery dies? there s a problem here in the acoustic pingers are not really intended to identify where the