French aviation investigators said the co-pilot of the Germanwings jetliner who crashed the plane in the French Alps last year had been referred to a psychiatric clinic just two weeks before deliberately killing all 150 people on board.
The findings by BEA (Bureau d'Enquêtes et d'Analyses), the French authority responsible for safety investigations into accidents or incidents in civil aviation, were included in a report issued Sunday, more than a week before the first anniversary of the March 24, 2015 tragedy.
The agency found that 27-year-old Andreas Lubitz had consulted several doctors about ongoing psychological issues in the months before the crash -- none of whom reported Lubitz's condition to either aviation authorities or officials at Germanwings.
Preliminary findings show that Lubitz had told the flight school for Lufthansa, the corporate parent for its budget carrier Germanwings, in 2009 that he had a "serious depressive episode," but Lufthansa certified him as fit to fly.
The BEA report cited a "lack of clear guidelines" in Germany's regulations over when a threat to public safety outweighs patient confidentiality.
Investigators are urging aviation bodies to mandate that all pilots undergo regular mental health checkups to detect any problems.
Lubitz crashed the Airbus A320 plane into a mountainside near the French village of Le Vernet during a flight from Barcelona, Spain to Dusseldorf, Germany. He was alone in the cockpit, having locked out Captain Patrick Sondheimer when the senior pilot when to the restroom.
Sondheimer could be heard on the plane's "black box" recorders frantically demanding Lubitz to open the door as it was making its final descent.