Germanwings captain Patrick Sondenheimer tried to break into locked cockpit door 'with an axe' as plane was descending

Prosecutors Andreas Lubitz locked the captain out of the Airbus A320 cockpit

The captain of the doomed Germanwings plane reportedly used an axe to break down the cockpit door in the final moments before his co-pilot “intentionally” descended the plane, German media has suggested.

Evidence from the cockpit voice recorder suggested the captain of the Airbus A320, who The Independent understands is named Patrick Sondenheimer, left the flightdeck mid-journey, presumably to go to the toilet. Prosecutors say he returned to find his co-pilot Andreas Lubitz had barricaded himself inside and had sent the plane into descent over the French Alps.

French investigators said the captain can be heard asking “several times” for access after identifying himself, but received no response. He then banged on the door before trying to forcefully gain entry, with one investigator telling The New York Times: “You can hear he is trying to smash the door down.” The German newspaper Bild quoted anonymous sources on Friday as saying Sondenheimer began trying to break the door down with an axe in a desperate attempt to get back inside.

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Sources told the newspaper he struck the door repeatedly up until the plane crashed into the mountain, possibly causing the banging sounds heard on the cockpit voice recorder.

Germanwings has confirmed that an axe was on board for safety reasons, as is routine on all Airbus A320 models. Investigators would not comment on whether it was used to gain entry to the cockpit.

The President of France's pilot union has since claimed the axe would have been kept in the cabin, telling BMFTV: "The only tools available in the cabin are crowbars."

The only sound heard from inside the cockpit is steady breathing, implying Lubitz was alive until the moment of final impact.