Black boxes crucial to finding disaster's cause

When investigators arrive at an aviation crash site, one of their first priorities is to locate the plane's black boxes, which can hold vital clues on what caused the aircraft to go down.

Despite the name, these two boxes - the flight data recorder and the cockpit voice recorder - are in fact bright orange with reflective stripes.

The digital flight data recorder gathers information about the speed, altitude and direction of the plane with enough storage for 25 hours of data, and the cockpit voice recorder keeps track of conversations and other sounds in the pilots' cabin.