The Germanwings crash that killed 150 people was likely caused by the co-pilot of the aircraft deliberately flying the plane into a mountain, according to an early investigation.
Andreas Lubitz was co-pilot aboard the Airbus A320 on March 24, when the crash occurred. The flight data recorder, commonly known as the black box, provides evidence that Lubitz locked the pilot, Patrick Sonderheimer, out of the cockpit before carrying out actions he would have known would lead to the destruction of the aircraft.
During the last eight minutes of the flight, the 28-year-old co-pilot ignored calls from the tower to resume a normal flight pattern, and also ignored sounds of the pilot pounding on the door and the screaming of passengers, all captured on the recorder.
"Based on audio taken from the voice recorder, the French authorities have come to the conclusion that after the aircraft had reached cruising altitude, the captain left the cockpit for a short time and was then unable to re-enter. It appears that the co-pilot, who had stayed in the cockpit, prevented the captain from re-entering by fully locking the cockpit door in order to then initiate the fatal descent," Germanwings managers wrote on the company Web site.
Lubitz had accumulated 630 hours in the cockpit since training with Lufthansa, the parent company of Germanwings. He had worked for the company since September 2013. Germanwings, in business since 2002, is a low-cost airline, based in Cologne, Germany.
There was no reason for alarm during the first 20 minutes of the flight, as the pilots spoke in a friendly and cordial manner with each other.
"We heard the flight commander prepare the briefing for landing at Düsseldorf and the response of the co-pilot seemed laconic. Then we heard the commander ask the co-pilot to take the controls," Brice Robin, a public prosecutor in France, said.
Following the timid response from Lubitz concerning flight plans, the pilot is heard handing over controls of the craft to the co-pilot. A seat is heard pressing backward, followed by the sound of a door being closed.
The flight monitoring system was then manually adjusted to lower the altitude of the aircraft. The pilot is soon heard at the door, identifying himself as the pilot, demanding to be let back into the cockpit. Controllers on the ground attempted to carry out a forced landing, and requested help from other aircraft in the area in their quest to contact the craft. An electronic code can normally be used to enter a locked cockpit door, but those codes can be overridden from the cockpit, a change made in the wake of the 9/11 terrorist attacks.
International airlines may now implement a "rule of two" for all flights in the wake of this incident. This rule would require two or more flight crew to be present in the cockpit at all times.
Although terrorism cannot be ruled out, there is no reason known to tie Lubitz to any terrorist organization.
