Aviation industry needs to learn from Germanwings crashFriday family crippled with sadnessCarol Friday honoured
A Victorian man whose wife and son were among the 150 people killed when suicidal Germanwings co-pilot Andreas Lubitz crashed a jet into the French Alps, is suing a US flight school he alleges failed to stop the tragedy.
Among explosive allegations made on behalf of David Friday are that the US training centre, owned by Germanwings parent company Lufthansa, negligently hid and failed to act on Lubitz's history of serious mental illness. 
Lawyers for the Friday family argue US Federal Aviation Authority rules require flight instructors to stop teaching students "suffering from psychological abnormality" and that they knew or should have known Lubitz was unstable and a danger to passengers.
The lawsuit was filed in the United States District Court in Arizona on Tuesday and states that had Lufthansa's Airline Training Centre Arizona exercised reasonable care it "could have prevented this predictable tragedy".
Mr Friday lost his wife Carol, 68, and 29-year-old son Greig when Lubitz locked the pilot out of the cockpit of an Airbus A320 and deliberately crashed the Dusseldorf-bound plane on   March 24, 2015.
Speaking to Fairfax Media, Mr Friday said the family's loss had been "devastating" and he was pursuing legal action against those he holds responsible in the hope it would prevent unnecessary deaths in the future.
"They were loved and appreciated by so many people. If their loss had been due to some genuine accident it may have been easier to bear," he said.
"We feel legal action against the flight school, who were aware of the pilot's mental problems, will ensure that they never again allow a pilot with known dangerous mental problems to be licensed to pilot a passenger plane."
Lubitz took 10 months leave from Lufthansa's flight school in Bremen, Germany, when he was suffering from a severe depressive episode, during which time he had signed "no-suicide pacts" with psychiatrists and was prescribed antidepressant medication, French investigators have revealed. However, he was cleared to resume training and passed his written exams in Germany in   October 2010.
His application was initially rejected by the Federal Aviation Authority, but Lubitz managed to go on to the next stage of his training at the Arizona campus where he spent four months, as is Lufthansa's practice for trainee pilots, before completing his training in   March 2011.
Mr Friday's lawyer, Jerry Skinner, said despite a management crossover between the Bremen and Arizona schools, and indications that red flags were raised in Arizona, the ATCA had denied knowing about Lubitz's medical history.
Post-crash accounts widely circulated in the media have included a claim that an unnamed person at the ATCA declared Lubitz "unflyable" and although Mr Skinner believes this did happen, it has not been officially recorded or acted on, he said.
"They have denied knowing of any evidence of him suffering from a mental disorder," he said.
"When he was denied his initial application after review by the FAA and the statement was made public that the company considered him 'unflyable' those two things together identified Arizona as part of the process and as a point in time when more questions should have been asked."
Mr Skinner, an aviation attorney based in the US and a co-associate of Australian firm LHD Lawyers, is also preparing to file a lawsuit against Germanwings in Germany.
"There are very few airplane crashes that occur where there is only one causal factor involved," he said.
Mr Friday's is not expected to be the only lawsuit filed against ATCA over the tragedy. Law firm Irwin Mitchell, representing the families of the British victims of the crash has also recently indicated it was preparing to sue and a US-based lawyer representing the families of dozens of other victims has also signalled an intention to pursue the school.
The airline initially paid ???50,000 ($74,000) per victim and offered ???25,000 more to each family, plus ???10,000 to each immediate relative including parents, children and spouses.
Mr Friday's lawsuit is seeking economic losses and damages for pain and suffering.
A Lufthansa spokeswoman said the company was aware of the Friday lawsuit and was in the process of assessing it, but added: "Generally, we still cannot see any prospects for this approach to succeed."