'Open the Damn Door' Screamed A320 Pilot at Andreas Lubitz

"For God's sake, open the door," Captain Sondenheimer shouted at Lubitz, with passengers heard screaming in the background, a transcript from the cockpit recorder published in the German newspaper Bild on Sunday revealed.

Minutes later, with no response from Lubitz, Sondenheimer could be heard attempting to smash the door with what appears to have been an ax, yelling at the still silent co-pilot to "open the damn door!"

Excerpts from the transcript published by the newspaper revealed that Sondenheimer had left the cockpit for a restroom break, telling Lubitz that he had not had time to go to the bathroom before leaving Barcelona for Dusseldorf. Before leaving, at approximately 10:27, Sondenheimer told Lubitz to prepare for descent and landing, with Lubitz answering using the phrases "we will hope" and "we'll see." Prior to leaving, the pilot told Lubitz "You can take over," after which a seat is heard being pushed back and a door can be heard opening and closing.

At 10:32, air traffic controllers called out to the copilot, with no response. Shortly after, a sink rate alarm is heard warning Lubitz of the plane's dangerous rate of descent, followed seconds later by a loud knock on the door by Sondenheimer, after which the Captain is heard shouting at Lubitz. At 10:35, "loud, metallic blows" are heard, and the captain shouts "open the damn door!", while an automated message saying "Ground. Pull up. Pull up" is heard

Investigators believe that the plane crashed into side of a mountain at 10:40. Bild notes that Lubitz could be heard breathing until the very end, but did not say a word following Sondenheimer's exit.

French officials say that the recording seems to indicate that Lubitz, 27, may have deliberately locked the captain out of the cockpit and steered the plane into the side of a mountain.

Investigators have also found that in addition to reports that he suffered from stress and depression, Lubitz also sought treatment for vision problems. Dusseldorf police are also said to have recovered a note indicating that Lubitz had been written off as sick on the day of the crash.

Bild also reported more details about the ongoing investigation, indicating that Lubitz's girlfriend, with whom he lived in Duesseldorf, was pregnant. Media have confirmed earlier tabloid reports that the woman, a secondary school in her 20s, had told her students that she was "going to be a mum," adding that she had planned to marry Lubitz, even though the pair is reported to have had an on-again/off-again relationship.

Investigators have yet to turn up a singular "smoking gun" which could explain Lubitz's alleged criminal action.