Andreas Lubitz, the co-pilot of the Germanwings flight which crashed in the French Alps in March, may have practised the crash on an earlier flight, according to a report by the French Civil Aviation Safety Investigation Authority (BEA), who's investigating the incident.
Lubitz is suspected of crashing the Germanwings' Airbus A320 into a mountain deliberately, after locking the pilot out of the cockpit. Flight 9525 from Barcelona to Dusseldorf crashed on March 24; all 150 people on board were killed.
According to German newspaper Bild, which quotes sources close to the investigation, Lubitz tried something similar on a different flight that same day, from Dusseldorf to Barcelona. He put the flight into a "controlled descent" for which there was "no aeronautical reason," the BBC reports.
It's also possible that Lubitz wanted not only to practice the descent, but actually crash that earlier flight, says Bild.
The new preliminary report by BEA, which includes data from the previous flight's black box recorder, shows that Lubitz selected an altitude of 100 feet on several occasions while the captain was out of the cockpit. The altitude was finally set to 25,000 feet seconds before the captain returned to the cockpit.
According to an April report from the French air accident investigation agency, Lubitz likely intentionally crashed the plane, speeding up several times as it descended. German prosecutors said in April that Lubitz performed Internet searches related to suicide as well as cockpit door security.