The newspaper referred to an interim report, due to be published by France's BEA crash investigation agency later on Wednesday. The document reveals that Andreas Lubitz allegedly practiced reducing flight altitude during the outbound flight from Dusseldorf to Barcelona on the same day when the crash occurred.
The Bild quoted sources close to BEA as saying that the report would point, among other things, to a "controlled descent that lasted for minutes and for which there was no aeronautical justification."
Lubitz is accused of deliberately flying the Airbus A320 jetliner into a mountainside during a flight from Barcelona to Dusseldorf on March 24, killing all 150 people onboard.
Using information obtained from the plane's flight data recorders, prosecutors said they believe that Lubitz locked the captain out of the cockpit and veered the plane into a deadly descent. They also said that Lubitz changed the settings to increase the plane's speed as the captain unsuccessfully tried to enter the cabin.
