"Clearer rules are needed to establish when it is necessary to lift medical confidentiality," investigator Arnaud Desjardin said at the launch of the report by the French crash investigation authority BEA at Le Bourget, near Paris. "Several doctors in private practice had the information [that Lubitz] was ill.This information was not passed on to aeronautical authorities or to his employer Germanwings."
The 87-page dossier says that Lubitz, 27, had shown “symptoms suggesting a psychotic depressive episode” in December 2014.
He had seen 41 doctors in five years, seven of them in the month before the crash, it reports.
German law prevented the doctors sounding the alarm about his state of mind and he was able to continue flying.
They also refused to speak to the investigators, as did members of Lubitz's family.
The report, which points out that the deliberate crash was a first in aviation history, also recommends regular analysis of pilots to check for psychological or psychiatric problems and warns they may be reluctant to declare they have problems for fear of mosing their licences.
The European Aviation Safety Agency (EASA) has already recommended stepping up medical testing for pilots, including more psychological tests.
No change to cockpit locking rule proposed
The French report does not propose an obligation to have two people in a plane's cockpit at all times, as has been recommended by the EASA following revelations that Lubitz locked the pilot out.
Some countries oppose the measure and the German pilots' union says it poses "risks that outweigh any supposed improvements in security".
Nor does it recommend changing the rule that the cockpit cannot be opened from outside because "the terrorist danger is still present", according to BEA chief Rémi Jouty.
The BEA's recommendations are not obligatory but the body has a great authority in international aviation circles.
Relatives to sue flying school
A German lawyer representing some of the families of the dead, 72 of whom sere German citizens, says they intend to sue the training school in the US that Lubitz attended.
Given that Lubitz interrupted his training there, the school should have flagged up his psychological problems, lawyer Christof Wellens said this month.
Lufthansa has paid 50,000 euros per victim as an initial payment and offered an additional 25,000 euros to each of the families plus 10,000 euros to each immediate relative including parents, children and spouse.