The families of three British victims killed in the Germanwings air disaster a year ago are to take legal action.
Paul Bramley, Martyn Matthews and seven-month-old Julian Pracz-Bandres all died when co-pilot Andreas Lubitz crashed the plane in the French Alps.
Lubitz, 27, was seen by 41 doctors in the years before the crash on 24 March.
Lawyers said a flight school where he trained should have prevented him from qualifying as an airline pilot and are planning legal proceedings against it.
The pilot crashed the aircraft into a mountain after locking the captain out of the cockpit. All 150 people on board Flight 9525 from Barcelona to Dusseldorf were killed.
Clive Garner, head of aviation law at Irwin Mitchell, said the victims’ families “deserve answers” as to how he was given clearance to qualify to fly.
“While nothing can bring their loved ones back, they want those who were responsible for allowing Lubitz to qualify as a pilot and fly commercial airliners to be brought to justice.
“To that end we have joined forces with other specialist law firms representing a large number of families from across the world as we prepare a group action against the US flight school in Arizona, who trained Lubitz and deemed him fit to fly airliners for Germanwings.”
Seven-month-old Julian, from Manchester, had been travelling with his mother, Spanish-born Marina Bandres Lopez-Belio, 37, at the time of the crash.
Mr Bramley, 28, from Hull, was studying hospitality and hotel management at Cesar Ritz College in Lucerne, Switzerland.
His father Philip has called for more stringent checks on pilots’ mental health and said they “should be tested much more regularly”.
Mr Matthews, a 50-year-old father-of-two from Wolverhampton, worked as a senior quality manager.
Earlier this month, a report by French investigators revealed Lubitz was urged to attend a psychiatric hospital weeks earlier, but his employer was never alerted.
They believe he brought down the plane deliberately and have called for medical confidentiality to be relaxed for pilots.
Lubitz had been suffering from severe depression, they said, but doctors had been unable to disclose this.
Both Germanwings and its parent company Lufthansa have previously said Lubitz had passed all tests of fitness to fly.
Lufthansa has also acknowledged it knew the co-pilot had suffered from severe depression in 2009 while training for his pilot’s licence.
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