It was the co-pilot of Germanwings Flight 9525, Andreas Lubitz, who was in the cockpit when the plane crashed into the French Alps. Investigators called it a "deliberate" move, one that killed Lubitz and 149 others. His motive is still unclear, leading to questions about how the aviation industry screens pilots for issues like mental health.
CBS News aviation and safety consultant Captain Chesley "Sully" Sullenberger - known for the Miracle on the Hudson -- says pilots who are not fit to fly should not fly. Currently the system relies on pilots to self-report any issues they may need help with.
"We need to make sure we have a just system, a just culture and not a punitive one, which might only drive problems underground where they can never be solved," said Sully. "We need to have a clear pathway so that when pilots need help they can get it. And when they are fit to fly come back to work and not face scrutiny that results in financial ruin or loss of career, unnecessarily."
According to investigators, Andreas Lubitz deliberately set the plane on a doomed descent. Data from an aviation flight-tracking service shows the altitude setting was turned down to 100 feet -- its lowest possible level. That action appears to firmly rule out any possibility of an accident.
"Overt action is required to reach up, turn a knob many times to change it from 38,000 feet, to in this case, to 100 feet ," said Sully. "One would never normally in flight set an altitude of 100 feet."
Watch the video at the top of this page to hear Sully's full analysis of the final moments inside the cockpit of Germanwings Flight 9525.
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