Maker of flight data recorder aboard AF447 has `` 100 percent '' recovery rate . Top executive says finding flight data recorder could reveal cause of air crash . Plane wreckage believed to be on Atlantic seabed , around 4,500 meters deep . Comment:
Maker of flight data recorder aboard AF447 has `` 100 percent '' recovery rate . Top executive says finding flight data recorder could reveal cause of air crash . Plane wreckage believed to be on Atlantic seabed , around 4,500 meters deep . Device 's underwater locator beacon has limited battery life .