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. Ironically, this auto-lock feature, which led to Lubitz having sole control of the plane, was introduced as a …