It's one of the most important pieces of forensic evidence following a plane crash: The so-called “black box." There are actually two of these remarkably sturdy devices: the cockpit voice ...

All six people aboard the plane − a pilot and copilot, two medical personnel, a patient and her mother − died in the crash ...

Investigators are on the scene again today, searching for the black box and other evidence to provide clues about how the tragedy occurred.