Both the robo-sub in the hunt for the missing Malaysia Airlines jet and the Australian ship towing it have defective transponders, officials said Thursday, NBC News reported. The U.S. Navy sub Bluefin-21 and the Australian defense vessel Ocean Shield each have transponders that have hardware defects that prevent the two devices from communicating with each other, according to a statement from the Australian government's Joint Agency Coordination Center. Ocean Shield is currently heading to Dampier, a port in the northwest of Western Australia, to receive spare transponder parts.
