As i said, assuming it still works. here's what they're going to be listening for. we've been talking about the black boxes and pingers and how they're activated almost from day one when they hit the water, we want to give you a demonstration with david sousy and director of special projects is with us. former transportation general mary schiavo and an lace analyst and veteran pilot miles o'brien. david, you have the pinger, explain how it works. >> this is the pinger, it gets replaced on the c check. there's one of these on the cockpit voice recorder and data