How Germanwings co-pilot Lubitz locked his colleague out of the cockpit: The post 9/11 safety system that led to disaster

The Airbus A-320 is fitted with a safety system, pictured, to prevent unauthorised access to the flight deck

The co-pilot blamed for deliberately crashing a passenger jet with 150 people on board into the Alps used post-9/11 safety mechanisms to carry out his plan.

Andreas Guenter Lubitz, 28, waited for his captain, Patrick Sondenheimer to leave the flight deck and go to the toilet before commanding the Airbus A-320 to descend.

Once out of the cockpit, the door locked automatically, in response to the 9/11 hijacks…

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