Lubitz Practiced Descending The Germanwings Plane

French officials on Wednesday said Germanwings co-pilot Andreas Lubitz practiced descending a previous flight before he crashed the plane in the French Alps on March 24, killing all 150 people on board including himself. In a report, the BEA investigation agency said Lubitz, 27, repeatedly put a previous flight into the same controlled descent that was used on the fated Germanwings A320 aircraft that flew from Barcelona to Dusseldorf. The pilot of the previous flight also appeared to have left the cockpit for some time, according to the preliminary report.

The practiced descent happened earlier in the day during the plane's outbound flight from Dusseldorf to Barcelona, the report said. Investigators said Lubitz set the altitude dial to 100 feet five times during the first flight. On the return flight back to Dusseldorf, Lubitz used the automatic pilot to deliberately accelerate and crash the plane, authorities said after studying flight data from a recovered black box.

Lubitz was said to have suffered depression. German prosecutors said last month Lubitz researched suicide methods and cockpit doors' security mechanisms on his home computer. The crashed flight's voice recorder revealed Lubitz locked the pilot, Patrick Sondenheimer, out of the cockpit before intentionally directing the plane down into the mountains. The harrowing audio showed Sondenheimer pleading for Lubitz to "open the damn door."