Here's what we know about the co-pilot who crashed Germanwings flight 9525
Lubitz was from Montabaur, in the Rhineland-Palatinate region of Germany, and had logged 630 flight hours before co-piloting the doomed aircraft.
Lubitz joined Germanwings in September 2013 after training at the Lufthansa Flight Training School in Bremen, and was praised by the Federal Aviation Administration (FAA) for "meeting or exceeding the high educational, licensing and medical standards established by the FAA," the Aviation Business Gazette reported in 2013.
The young pilot's evident skills landed him a spot in the prestigious FAA Airmen Certification Database.
He was a member of the LSC flight club, which posted a death notice on its website naming him, according to the Wall Street Journal: "Andreas became a member of the club as a youth to fulfill his dream of flying," it said.
"It was his dream fulfilled, the dream he so dearly for with his life. The members of the LSC Westerwald mourn Andreas and the other 149 victims of the disaster. Our deepest sympathy goes out to the victims of all nationalities."
Officials said Thursday that Lubitz showed a "willingness to destroy this plane," the Daily Beast reports, and he could reportedly be heard breathing until the plane crashed, ruling out any kind of medical emergency that may have left him incapacitated.
Lubitz apparently locked the pilot out of the cockpit before deliberately pushing the botton to start the plane's descent.
The revelation that Lubniz intentionally downed the plane may answer one of investigators' most pressing questions, including why air traffic controllers were unable to make contact with the plane during the flight's final two minutes, and why the plane made a "very long descent at normal speed without any communications, though the weather was absolutely clear."
Officials are currently investigating Lubitz's background, but a German security official has said there are no indications that Lubitz had any connections to terrorism, according to the NBC.
The more likely explanation seems to be that Lubitz was suicidal.
"While incredibly rare for a pilot to kill himself - and everyone else on a plane - there is both national and international precedent for what experts call 'aircraft-assisted pilot suicides,'" Terrence McCoy wrote in the Washington Post. "According to Federal Aviation Administration data, 24 American pilots have killed themselves while flying their planes in the last two decades."