Mystery deepens over co-pilot who crashed jet

The co-pilot of the Germanwings airliner accused of intentionally crashing the jet into the Alps appeared to be happy with his job and didn't exhibit any clear signs for why he would send 149 people and himself hurtling into the side of a mountain.

The startling disclosure that Andreas Lubitz, 27, deliberately worked to "destroy" the jet — as a French prosecutor put it — has the entire world wondering what possessed him to commit such a horrific act.

"We can only speculate what might have been the motivation of the co-pilot," Carsten Spohr, CEO of Germanwings parent company Lufthansa, said in Cologne, Germany, on Thursday. "In a company that prides itself on its safety record, this is a shock. We select cockpit personnel carefully."

As investigators searched his apartment in Düsseldorf and his parents' house in Montabaur, a quiet town in west Germany where he often spent time, a picture emerged of a skilled pilot with a passion for flying and no known terrorist connections.

Marseille prosecutor Brice Robin said Lubitz, a German citizen, was not on any terrorist watch list before Germanwings Flight 9525 began an eight-minute descent from 38,000 feet, smashing into a 6,000-foot mountain Tuesday.

Transponder data shows that the autopilot on the airliner was reprogrammed in the cockpit to change the plane's altitude from 38,000 feet to about 100 feet, according to an analysis by the aviation website FlightRadar24.com.

Robin wouldn't divulge any information on Lubitz's religion or ethnic background that might shed light on a motive.

The cockpit voice recorder recovered at the crash scene revealed the pilot had left the cockpit, and when he returned, Lubitz refused to let him in and intentionally took down the jet, Robin said.

"This was voluntary, this was deliberate," he said. "He refused to open the cabin door in order to let the pilot back in."

Lubitz said nothing during the descent but could be heard breathing until the crash, Robin said, adding that passengers could be heard screaming in fear.

The data recorder for the flight from Barcelona to Düsseldorf has not been found.

A federal law enforcement official told USA TODAY the FBI has been running the flight manifests through its databases but has found no connection of anyone aboard to terrorism.

Lufthansa CEO Spohr said there was nothing to cast doubt on Lubitz's competence or skills. The company does annual medical checks but does not require psychological assessments after training. He stopped short of calling the crash a suicide mission or an act of terror.

"If one person kills himself and 149 other people, a word other than suicide should be used," he said.

Peter Ruecker, a member of the LSC Westerwald e.V glider club, who watched Lubitz learn to fly as a teenager, said Lubitz showed no signs of depression last fall when he renewed his glider pilot's license. "He was happy he had the job with Germanwings, and he was doing well," Ruecker told the Associated Press. "He gave off a good feeling."

Ruecker said Lubitz was a "rather quiet" but friendly young man when he first came to the aviation club when he was 14 or 15. "Andreas became a member of the club as a youth to fulfill his dream of flying," the club said in a statement on its website released before the disclosure that the co-pilot downed the jet. "He fulfilled his dream, the dream he now paid for so dearly with his life."

Klaus Radke, chairman of the club, told the German newspaper Rhein Zeitung that he met Lubitz a couple of times. "I got to know him as a very nice, funny and polite person." Radke said. He said it will take some time to understand what really happened: "We shouldn't jump to conclusions."

In Montabaur, neighbors of his parents were similarly stunned by the suggestion that Lubitz could be responsible for such an unfathomable incident. Johannes Rossmann recalled Lubitz as appearing in good health and as avid runner. Over the years, Lubitz ran a10-kilometer race in Montabaur and three times ran the Lufthansa Frankfurt Marathon, according to records kept by organizers.

"I do not believe he killed himself and claimed other people's lives," the 22-year-old Rossmann told the AP. "I can't believe it until it is 100 percent confirmed."

Lubitz began training as a pilot in Bremen, Germany, in 2008 and later in Arizona, Spohr said. He joined Germanwings in September 2013 and had flown 630 hours before Tuesday's crash.

Spohr said there was a brief interruption in his training in 2009, but Lubitz had completed qualifications for the job. Such a break is not unusual, but the company will look into what happened during that time, Spohr said. German media outlets quoted unidentified friends of Lubitz as saying he took time off for "depression" and "burnout."

"He passed all medical tests, he passed all aviation tests, he passed all checks," Spohr said. "He was 100% able to fly without any limitations, without any reservations. His accomplishments were excellent. Nothing was noticed that wasn't proper."

Before he began working for the company, there was an 11-month waiting period, which is not unusual, Spohr said. During that time, Lubitz worked as a full-time steward.

The captain, who was identified as Patrick Sonderheimer by multiple media outlets, had more than 6,000 hours of flying time and had been with Germanwings since May 2014. He previously flew for Lufthansa and Condor. Authorities did not officially identify the pilot.

In Lubitz's village of Montabaur, neighbor Johannes Rossbach, 23, said he would often see Lubitz jogging. "He was very polite. He would always say hello and goodbye," he said, according to London's Daily Mail. "There certainly seemed nothing out of the ordinary about him."

A deleted Facebook page that appears to be Lubitz's showed a smiling man posing in front of the Golden Gate Bridge in California. The page was wiped sometime in the past two days, according to the AP.

The page listed his interests, including German electronica band Schiller, French superstar DJ David Guetta, his local Burger King, 10-pin bowling, aviation humor and a technical website about the A320 model of aircraft he flew into a mountainside.

Lubitz is listed on the Federal Aviation Administration's Airmen Certification Database. He received his student pilot's license June 18, 2010, and his private pilot license Jan. 6, 2012. The database is for certified pilots who have met or exceeded the high educational, licensing and medical standards established by the FAA, according to the Aviation Business Gazette.

The evidence Lubitz intentionally brought down the jet is likely to renew concerns about suicidal pilots. In 1999, EgyptAir Flight 990 from Los Angeles to Cairo crashed in the Atlantic Ocean, killing all 217 people on board.

An investigation by the National Transportation Safety Board found that the Egyptian pilot brought the plane down intentionally. However, the Egyptian Civil Aviation Agency determined that the plane crashed because of a mechanical failure.

Contributing: Jabeen Bhatti and Katharina Wecker in Berlin, and Doug Stanglin and John Bacon in McLean, Va.