The co-pilot of Germanwings Flight 9525 who apparently chose to crash the jetliner into a mountain last Tuesday had vowed to "do something" that would make people remember him, his former girlfriend has told a German newspaper.

The 26-year-old flight attendant, identified by the tabloid Bild as Mary W., was quoted as saying Andreas Lubitz, 27, had "burnout-syndrome" and she had been worried about his increasingly erratic behaviour.

Andreas Lubitz

Andreas Lubitz's former girlfriend said the man suspected of deliberately flying a Germanwings plane into a mountain, killing all 150 people on board, used to wake up at night screaming, 'We're going down.' (Getty Images)

The woman said Lubitz would have horrible nightmares and would wake at night screaming, "We're going down."

When she heard about the crash in the French Alps — which killed all 150 people on board — she remembered that Lubitz had told her last year: “One day I will do something that will change the whole system, and then all will know my name and remember it."

"I never knew what he meant, but now it makes sense," she told Bild. She said they dated for five months last year but she decided they should end the relationship after "it became increasingly clear he had a problem."

The woman spoke of his "health problems," described him as being agitated when he spoke of his work, and remembered him saying he didn't think he could realize his dreams of becoming a long-haul pilot and captain.

She added, "He knew how to hide what was really going on and how to hide it from other people."

Investigators say they have found evidence that Lubitz hid an illness of some kind from the airline, including a torn-up doctor's note that would have kept him off work on the day of the crash.

The Wall Street Journal, quoting a "person familiar with the investigation," said Lubitz had been excused from work by his neuropsychologist for a period that included last Tuesday.

Prosecutors didn't specify what illness Lubitz may have been suffering from, or say whether it was mental or physical. German media reported that the 27-year-old had suffered from depression. The New York Times and Germany's Bild am Sonntag weekly also reported Saturday that Lubitz had eye problems.

German prosecutor Christoph Gumpa said investigators, after searching the co-pilot's apartment in Dusseldorf and his parents home in Montabaur, did not find a suicide note or anything to indicate a religious or political motive for crashing the plane.

The Duesseldorf University Hospital on Friday said Lubitz had been a patient there over the past two months and last went in for a "diagnostic evaluation" on March 10. It declined to provide details, citing medical confidentiality, and denied reports it had treated Lubitz for depression.

Investigators believe Lubitz locked his captain out of the cockpit during a flight from Barcelona to Dusseldorf, ignoring the Airbus A320 pilot's frantic efforts to re-enter while the plane continued to descend for eight minutes at full speed.

Germanwings said both pilots on the plane had medical clearance, and it had received no sick note for the day of the crash. Medical checkups are done by certified doctors and take place once a year.

Parent company Lufthansa is offering immediate financial assistance of up to 50,000 euros ($68,600 Cdn) per passenger to relatives of the crash victims, Reuters reported on Friday.

Lubitz's father 'completely broken' 

Lubitz's father was distraught with grief over his son's death and over what he may have done, the mayor of a town close to the crash site said Saturday.

Bernard Bartolini, the mayor of Prads-Haute-Bleone, said he met the father of Andreas Lubitz at a memorial late Thursday for relatives of those who died in the crash.

"He was distraught with grief. He was a completely broken man who is carrying all the responsibility of this drama on his back," Bartolini said on BFM-TV. "He lost a loved one, but also because his son is perhaps the (cause) of this tragedy."

Lubitz also frequented a gliding club near the crash site as a child with his parents, according to Francis Kefer, a member of the club in the town of Sisteron.

Kefer told i-Tele television that Lubitz's family and other members of the gliding club in his hometown of Montabaur came to the region regularly between 1996 and 2003.

The crash site is about 50 kilometres away from the Aero-club de Sisteron glider airfield.

Officials at the club wouldn't comment Saturday.

With files from The Associated Press and Reuters