first officer and the captain. focusing on them. they want to know essentially the important information, who made that last radio communication, the good night malaysian 370. because within two the nights of that communication, that's when the transponder data was turned off, that's when the radio silence began, the implication being whoever is making that last radio message potentially was the one in control of the aircraft when it took the left turn and when it took this passage. the investigators having played these audio recordings to friends and colleagues say they are unable to at this stage to tell who it was making that last radio communication. we do know that the first officer would have been in control if of making radio communications on the ground when the aircraft is pushing back from the stand when it was taxiing. but in the air, of course, we're told that it could have been