The co-pilot accused of deliberately crashing a plane in the French Alps with the loss of 150 lives was happy in his job, members of his flying club have said.
Details about the life of German national Andreas Lubitz emerged after a French prosecutor concluded the 27-year-old had wanted to "destroy the plane" by flying it into a mountainside.
Marseille prosecutor Brice Robin said he activated the descent button and refused to open the cockpit door to the pilot, ultimately killing all 150 people on the Barcelona to Dusseldorf flight.
The revelation has led to intense speculation about what may have prompted Mr Lubitz to have deliberately caused the plane to plummet. Here is what we know so far:
:: French prosecutor Mr Robin said Mr Lubitz had never been flagged as a terrorist. When pressed over Mr Lubitz's religion, he said: "I don't think this is where this lies. I don't think we will get any answers there."
:: Local media reports suggest Mr Lubitz may have suffered from depression.
:: According to Carsten Spohr, chief executive of Lufthansa, Germanwings' parent company, Mr Lubitz took a break in training in 2009 for several months. He was later reassessed and deemed fit to continue. Mr Spohr did not comment on his reason for taking a break.
:: Germany's FAZ.NET claims to have interviewed the mother of one of his former classmates. She said he told her daughter about the break in training several years ago. It was apparently down to "burnout or depression," she said.
:: Mr Lubitz had worked as a pilot for Germanwings since September 2013.
:: He had clocked up 630 hours in the cockpit.
:: It is reported Mr Lubitz had been included by the US Federal Aviation Administration (FAA) on its database to show he had met or exceeded its pilot certification standards, which aim to "reduce pilot errors that lead to fatal crashes".
:: He underwent a regular security check on 27 January. Nothing untoward was found, the local government in Dusseldorf said. Previous security checks in 2008 and 2010 also showed no issues.
:: According to Lufthansa, Germanwings pilots undergo medical tests once a year. However they are only required to undergo psychological tests once, before they are accepted as pilots.
:: He trained at the Lufthansa flight school in Bremen.
:: Lufthansa said he passed all the relevant examinations necessary to become a pilot and was deemed "100% airworthy".
:: Mr Spohr said he was "stunned" at the claim made against the co-pilot, saying: "We choose our staff very, very carefully."
:: Mr Lubitz served as a flight attendant while waiting to become a pilot.
:: He is also thought to have trained in Phoenix, Arizona.
:: Lubitz lived with his parents in Montabaur in the west German state of Rhineland-Palatinate. He reportedly had a second home in Dusseldorf.
:: He learnt to fly as a teenager at a glider club in Montabaur.
:: According to members of the club he was enthusiastic about his job with the airline. Club member Peter Ruecker said: "He has happy he had the job with Germanwings and he was doing well. I can't remember anything where something wasn't right."
:: Mr Ruecker recalled Mr Lubitz as "rather quiet but friendly" when he first joined the club as a teenager, wanting to learn to fly.
:: He said Mr Lubitz was a keen half-marathon runner and had a girlfriend.
:: Club members also said he had been upbeat when he returned to the club in the autumn to renew his glider's licence.
:: Klaus Radke, the club's chairman, said he did not believe the conclusion of Marseille prosecutor Brice Robin. "I don't see how anyone can draw such conclusions before the investigation is completed," he said.
Previous pilot suicides
Although rare, there have been previous instances of suspected pilot suicide.
The most infamous likely - but still disputed - cases of pilot suicide was the 1997 Silk Air crash in Indonesia, in which 104 people died.
A US-led investigation concluded it had been caused deliberately, probably by the captain who had serious personal problems.
A Mozambique Airlines plane crash that killed 33 people in Namibia in 2013 is also believed to have been a case of pilot suicide.