Günter Lubitz, left, and aviation expert Tim van Beveren hold a news conference in Berlin on Friday at which they disputed official findings that co-pilot Andreas Lubitz, Günter Lubitz’s son, intentionally caused the Germanwings plane crash in the French Alps two years ago. (Felipe Trueba/European Pressphoto Agency)

The father of a German pilot who was found by investigators to have purposely crashed a commercial airliner into the French Alps in 2015 held a news conference Friday in which he sought to cast doubt on the image of his son as a mass murderer.

Günter Lubitz unveiled his arguments, based on a report by aviation journalist Tim van Beveren, exactly two years after his son, Andreas Lubitz, 27, is believed to have crashed Germanwings Flight 9525, killing all 150 on board. According to van Beveren, German and French authorities focused too quickly on Lubitz, the co-pilot, as the sole potential culprit, a “bias” that compromised their investigations. Van Beveren and the elder Lubitz also rejected the notion that the co-pilot was suffering from depression at the time of the crash.

In January, a German prosecutor concluded — as had French investigators in a report issued a year ago — that the crash had been deliberately instigated by the suicidal and mentally ill 27-year-old. An analysis of the search history on Andreas Lubitz’s tablet computer found, according to the prosecutor, that he had researched methods of suicide and the mechanisms for locking a cockpit door, presumably to prevent the pilot from reentering after using the bathroom. Lubitz was also found to have rehearsed the downing of the plane on a previous flight by changing the aircraft’s altitude settings.

[French prosecutor: Co-pilot took doomed flight on deliberate dive]

The attempt by Lubitz’s family to clear his name outraged victims’ relatives.

Debris at the crash site of the Germanwings Airbus A320 during search-and-rescue operations in March 2015. (Sebastien Nogier/European Pressphoto Agency)

“This completely lacks respect, to schedule it for exactly the same day,” said Josef Cercek, 72, whose daughter, Sonja, a Spanish teacher, died in the crash along with 16 of her students.

“They’re trying to cope with their guilt of simply ignoring their son’s depression,” said Klaus Radner, 61, the father of opera singer Maria Radner, who was killed with her partner and their 18-month-old child. “They should get psychological help like I did.”

Günter Lubitz said that he had chosen the date for the news conference partly to ensure that his side of the story would be heard but that he had not intended to hurt the victims’ families. After giving a brief introduction, he mostly sat silently as van Beveren made his case. Why, the journalist asked, had investigators consulted no “human factor” experts — specialists in determining human causes of a crash? He also questioned the validity of the flight recorder data and assumptions about Andreas Lubitz’s motive in adjusting altitude settings on the earlier flight.

Van Beveren did not offer an alternative explanation for how the crash occurred.

According to Christoph Kumpa, the lead German investigator, the co-pilot suffered from an unspecified psychological condition and was on medication at the time of the crash. He was also found to have visited several doctors for an eye problem he feared could cost him his career as a pilot.

“There’s no doubt that the co-pilot alone was responsible for the crash and presumably carried it out with suicidal intent,” Kumpa said Thursday.

[Doctors thought Germanwings co-pilot was unfit to fly, prosecutor says]

While some relatives of the victims expressed sympathy for Lubitz’s parents, to Klaus Radner, the news conference Friday amounted to a “provocation.” He was already upset, he said, by the motif the co-pilot’s family chose for his gravestone — a mountain landscape resembling the crash site — and by the newspaper ad they took out a year after the crash that described him as a “lovable, valuable” person.

“Every day I wake up with the pain, and every day I go to bed with it,” Radner said.

Financial compensation for relatives of plane-crash victims is meager in Germany compared with that in the United States. Germanwings’ parent company, Lufthansa, said it paid out more than it was legally obliged to, but lawyers for the families say the amounts were often inadequate to address the financial consequences of the disaster.

Josef Cercek, who raised his daughter alone after his wife died when Sonja was 7, said he received less than $11,000 because Sonja had married a few months before the crash.

“She always used to say to me: ‘Don’t worry and don’t save anything. I will take care of you when you’re old,’ ” he said. But, he added, “No money in the world will bring my daughter back.”

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