The Germanwings co-pilot, suspected of deliberately crashing a jet in the French Alps, rehearsed the fatal manoeuvre on the morning of the disaster, and had twice been refused medical papers needed to fly, investigators said on Wednesday, May 7.

Just over two minutes before the crash, the French military weighed in, trying three times to contact the crew on an emergency frequency, followed by a call from another plane.

Finally the aircraft's ground-proximity warning system kicked into life, urging the co-pilot to "pull up."

Reviewing Lubitz's training and career, the BEA said his professional level was judged to be "above standard".

However, it said the aeromedical centre of Lufthansa, the parent company of Germanwings, twice refused to renew his medical certificate in 2009 when he was undergoing treatment for depression. Lubitz broke off his pilot training from November 2008 to August 2009 due to his illness.

After gaining a certificate in July 2009, Lubitz's pilot's licence, which is always valid for one year only, contained a note requiring aeromedical doctors to contact licensing authorities before the certificate could be extended or renewed.

Investigators in Germany have found torn-up sick notes, including for the day of the crash, indicating that Lubitz was concealing an illness from his employers. They also uncovered Internet searches made by Lubitz in the week before the tragedy on suicide methods and cockpit door security.

The German government plans to name a former diplomat, Steffen Rudolph, as an ombudsman for relatives of the victims, government sources told Reuters.

The BEA will issue a final report in about a year that may include recommendations on cockpit doors and the handling of pilots' medical records by the airline industry.

A body of a victim is airlifted by a French Gendarmerie rescue helicopter. Reuters photo

The French agency declined to speculate on any recommendations but said it would examine the balance to be struck between medical confidentiality and air safety.

It promised also to look at where to draw the line between the need to prevent possible attacks by passengers and the need to prevent a repeat of incidents such as the Germanwings crash.

Cockpit doors were specially strengthened to protect pilots after the attacks on the United States on Sept. 11, 2001.

The BEA said it had found six previous accidents since 1980 in which deliberate actions by crew may have played a part.

These included a remarkably similar crash of an Embraer 190 jet in Namibia in 2013 in which 33 people died after the co-pilot left the captain alone in the cockpit. The jet was ordered to the ground by changing autopilot altitude settings.

On at least two other occasions, there were two pilots in the cockpit but one was not able to counter the other's actions.

Many airlines have recently made it compulsory to have two people in the cockpit to help prevent accidents, but Jouty said accident records suggested this would not be an automatic cure.

Andreas Lubitz runs the Airportrace half marathon in Hamburg in this September 13, 2009. Reuters photo