Paris (AFP) - Air France and Airbus will go on trial on Monday on charges of involuntary manslaughter over the fatal 2009 crash of a jet heading to Paris from Brazil, killing all 228 people aboard.
Victims' families and some aviation experts say the pilots were insufficiently trained to handle a loss of speed readings caused by crucial equipment freezing over in a storm.
Flight AF 447 from Rio de Janeiro plunged into the Atlantic Ocean in the early hours of June 1, 2009, after entering a zone near the Equator known for strong turbulence.
The Airbus A330 was carrying 12 crew members and 216 passengers.It was the carrier's deadliest crash.
It took nearly two years to locate the bulk of the fuselage and recover the "black box" flight recorders.
French flagship carrier Air France and aircraft maker Airbus were charged as the inquiry progressed.
Experts determined the crash resulted from mistakes made by pilots disorientated by so-called Pitot speed-monitoring tubes that had frozen over in thick cloud.
But investigating magistrates overseeing the case dropped the charges in 2019, a decision that infuriated victims' families.
Prosecutors appealed against the decision and in 2021 a Paris court ruled there was sufficient evidence for a trial to go ahead.
Ophelie Toulliou, who lost her brother on the flight, said it was essential "the truth come out, and that the sentences, if deserved, are handed down".
"But the message is also to make companies that think they're untouchable understand 'You're like everyone else and if you make mistakes, they will be punished,'" she told AFP.
'Lost our speeds'
The court will hear testimony from dozens of aviation experts and pilots over two months of hearings, and each company faces a maximum fine of 225,000 euros ($220,000).
There will also be analysis of the final minutes in the cockpit before the plane went into free-fall after entering a so-called "intertropical convergence zone" that often produces volatile storms with heavy precipitation.
In the cold, the Pitot tubes froze, a problem that had already been reported by other pilots.The tubes were quickly replaced on planes worldwide in the months after the accident.
"We've lost our speeds," one pilot is heard saying in the flight recordings, before other indicators mistakenly show a loss of altitude and a series of alarm messages appear on the cockpit screens.
The pilots start climbing and even though a "STALL" alert sounds, reach 11,600 metres (38,060 feet).
"I don't know what's happening," one of the pilots is heard saying as the stall begins.
Training overhaul
Air France pilots' union SPAF said it was now "indispensable for a court to hear all the parties and decide where responsibility lies in a public hearing".
The crash prompted an overhaul of training protocols across the industry, in particular to prepare pilots to handle the intense stress of unforeseen circumstances.
Pilots are also now required to continually practice stall responses on simulators.
"That was the big change after this accident for all civil airline companies.Before, it was something pilots learned in basic training and then they were never trained again," one airline executive told AFP, on condition of anonymity.
Testimony will also be heard from some of the 476 members of victims' families who are civil plaintiffs in the case.
But Nelson Faria Marinho, president of the Brazilian association of victims' relatives, said, "I'm not expecting anything from this trial."
"Even if there is a conviction, who will be punished?The CEOs?They were changed at Airbus and Air France a long time ago," he told AFP during an interview at his Rio home.
He will be represented by former French pilot Gerard Arnoux, who has advised several of the victims' families and wrote a book titled "Rio-Paris Is Not Responding: AF447, the Crash that Should Not Have Happened".
