A transcript of the cockpit voice recorder has shown that the captain of Germanwings flight 4U 9525 desperately attempted to get back onto the flight deck before it crashed.

It makes for difficult reading – a transcript of the last 13 minutes of flight 4U 9525. The pilot tries in vain to save the flight. The co-pilot’s silence.

The transcript reveals that Captain Patrick Sondenheimer screamed as he banged on the cockpit door, pleading with the co-pilot: “For God’s sake, open the door!”

Then, minutes later, again banging, pounding and an increasingly desperate voice: “Open the damn door!”

Thirteen minutes later, the plane crashed into the French Alps.

A leaked recording of the plane’s cockpit voice recorder has been obtained by German newspaper Bild.

It reveals that many of the passengers knew what was going on – with screams for several minutes heard in the background while Captain Patrick Sondenheimer tried to get Andreas Lubitz to open the door– terrified screams of those who realised the pilot was locked out of his own flight deck.

The transcript also reveals co-pilot Andreas Lubitz suggesting that the captain go to the toilet during the flight several times.

Related content: Captain Patrick Sondheimer. That’s the pilot’s name you want to remember.

According to Bild’s report, Sondenheimer told co-pilot Lubitz that he didn’t manage to go to the bathroom before takeoff in Barcelona. Lubitz tells him he can go anytime.

The flight – which was to be two hours in duration –  took off 20 minutes late. After reaching cruising altitude, Sondenheimer asked Lubitz to prepare the landing.

Once he completed the task Lubitz again tells the captain he “can go anytime.”

The captain then says, “You can take over.” His seat is heard moving.

At 10:29 a.m., air traffic radar detects that the plane is starting to descend.

According to Bild:

• The flight took off 20 minutes late, and Capt. Patrick Sondenheimer apologises for the delay and says they will try and make up for it in the air.

• Before takeoff, the captain tells co-pilot Andreas Lubitz that he didn’t manage to go to the bathroom in Barcelona. Lubitz tells him he can go anytime.

• 10:27am: The plane reaches its cruising altitude of 38,000 feet

• The captain asks the co-pilot to prepare the landing.

• Lubitz repeats to the captain, “You can go now.” There is the sound of a seat moving backward. After that, the captain is heard saying, “You can take over.”

• 10:29: Air traffic radar detects that the plane is beginning to descend.

•10:32: Air traffic controllers contact the plane and receive no answer. Almost at the same time, an alarm goes off in the cockpit saying “sink rate”.

• 10.30 – 10.34: There are loud bangs on the door. Sondenheimer screams “For God’s sake, open the door!”

• Passengers can be heard screaming in the background.

• 10:35: loud metallic bangs can be heard as though someone is trying to knock down the door. The plane is at about 23,000 feet.

• 90 seconds later: Alarm says: “Terrain — pull up!” The plane is at about 16,400 feet. The captain is heard screaming, “Open the damn door!”

•10:38: The plane is descending toward the French Alps, and the co-pilot can be heard breathing. The plane is at about 13,100 feet.

•10:40: It sounds like the plane’s right wing scrapes a mountaintop, then screams can be heard one more time. Those are the last sounds on the voice recorder.

Much attention has focused on Lubitz’s state of mind with suggestions that he may have had mental health issues.

The Wall Street Journal reports that 27-year-old Lubitz was being seen by a neuropsychologist for depression.

The doctor had given Lubitz a note excusing him from the work the day of the crash but he ignored the advice and reported to work.

German prosecutors reported that Lubitz destroyed the doctor’s notes for the day of the crash and other days – with mounting evidence that Lubitz hid his “medical illness” from his employer and colleagues. They refused to say if the hidden illness was depression.

It has been reported that Lubit’s pilot’s license was up for renewal in July and would be in jeopardy if he was diagnosed as mentally ill.

As investigators scramble to understand the motivation for the mass murder families of the passengers wait for news of their loved ones identification.

Fairfax Media reports that relatives of Australian victims Carol and Greig Friday plan to visit the Germanwings crash site today to say farewell.