Germanwings Pilot Locked Out of Cockpit Before Crash

In a stunning twist to the investigation of the recent Germanwings airplane crash that killed 150 people on board, French prosecutor Brice Robin on Thursday has said that the co-pilot appeared to want to "destroy the plane."

During the news conference, Robin insisted that the co-pilot, a German national from Montabaur was not a known terrorist.

With the voice recordings recovered from the cockpit recorder, it was discovered that the co-pilot of the Germanwings 9525, Andreas Lubitz was said to have had sole control of the plane prior to the crash.

The black box recordings also revealed that the main pilot (name withheld) had left the cockpit and could not get back in. His knocks on the door got more frantic when the plane started to plummet towards the earth.

A senior military investigator in charge of the investigation said, "The guy outside is knocking lightly on the door, and there is no answer. And then he hits the door stronger, and no answer. There is never an answer ... You can hear he is trying to smash the door down."

He added, "You can hear he is trying to smash the door down."

It is still unclear why the pilot left the cockpit but based on the recordings obtained, the two pilots could be seen having a "very smooth, very cool" conversation during the early part of the flight.

The main pilot had over 6000 hours of flying time while the co-pilot Lubitz had 630 hours and has been a part of Germanwings since September 2013.

The investigator said, "We don't know yet the reason why one of the guys went out. But what is sure is that at the very end of the flight, the other pilot is alone and does not open the door."

Prior to the crash, the plane was halfway through its flight flying at an altitude of 38,000 feet. It descended to 6,000 feet in just 8 minutes before crashing in the French Alps.

During this time, the co-pilot is said to have made no efforts to respond to the radio calls from French air traffic controllers and the matter was reported to the authorities when the plane completely slipped from their radar screens.