buoys are that the planes will carry, some of them at least, they'll drop these sonar buoys in the water and they'll be listening, hoping to find some sort of ping from those flight data and voice recorders. >> well, in the air france search, wolf, we didn't use buoys. we used towed pinger locators which are towed from ships. i'm not sure there's a buoy that's capable of listening to this, but that would be ideal to get a large field out there which could direction find to where the pings are coming from, if they have that capability. >> we're told they do. but go ahead, richard. >> let me just amplify a little bit on what you were just saying there. the reason they are deploying these buoys, these transmitters, is not really to hear the pings because, as your other guest says, it would just be impossible for that. the reason they're doing this is to monitor the current and the