Air France and aircraft maker Airbus faced charges of involuntary manslaughter when they stood trial on Monday over the 2009 crash of a flight from Brazil, which killed all 228 people on board.
The case focuses on pilot training and a defective speed monitoring probe, which was quickly replaced on planes worldwide in the months after the accident.
Flight AF 447 from Rio de Janeiro to Paris plunged into the Atlantic Ocean during a storm in the early hours of 1 June 2009, after it encountered strong turbulence.
The A330 was carrying 12 crew members and 216 passengers, including 61 French citizens.
It was Air France's deadliest crash in history.
If convicted, each company faces potential fines of up to €225,000, and. No one risks prison as only the companies are on trial. Still, the families see the trial itself as important after their long quest for justice.
"One of the main expectations of the victims' families is obviously to obtain the truth so that they can understand what precisely happened that night on board this aircraft, why it crashed into the sea, and why their loved ones, the 228 people on board, died" said Sebastien Busy, a lawyer for some of the families of the victims of the Rio-Paris flight.
Some of the victim's families have said the court case is the "light at the end of a long tunnel".
"Thirteen years later, we have a trial, a trial that, for me, is not that interesting, personally, since it will not bring my daughter back to me,” says Corinne Soulas, a mother of a crash victim.
“But I think it is important, once again, to remember this accident in people's minds, to bring it back to life and then, above all, to define the responsibilities, because there were responsibilities that need to be clarified."
“We made a promise to our loved ones to have the truth for them and to ensure that they didn’t die for nothing,” Ophelie Toulliou, whose 27-year-old brother Nicolas was killed, told The Associated Press. “But we are also fighting for collective security, in fact, for all those who board an Airbus every day, or Air France, every day.”
She said the companies present themselves as “untouchable,” and that Airbus made no effort to address families’ concerns. “For them, we are nothing. They did not lose 228 people. They lost a plane.”
Air France and Airbus were charged during an inquiry into the crash, with experts determining it resulted from mistakes made by pilots after they became disorientated by a temporary loss of data from iced-up sensors.
Both companies have denied any criminal negligence and investigating magistrates overseeing the case dropped the charges in 2019, attributing the crash mainly to pilot error.
That decision infuriated victims' families. In 2021 a Paris appeals court ruled there was sufficient evidence to allow a trial to go ahead.
The AF447 crash sparked a broad rethink about training and technology and is seen as one of a handful of accidents that changed aviation.