French investigators say pilot error, defective sensors, inadequate training and insufficient oversight led to the loss of an Air France passenger plane over the Atlantic in 2009.
The Airbus A330 on a flight from Rio de Janeiro to Paris plunged into the south Atlantic during a storm on 1 June 2009 killing 228 people.
The final report by France's BEA aviation authority has upheld initial findings that the crew mishandled their response to the loss of speed readings from faulty sensors that became iced up in turbulent conditions.
According to the flight recorders, the plane plunged for four minutes in darkness in an aerodynamic stall while the pilots failed to react to repeated stall alarms.
The BEA said France's flag carrier was subject to less inspection than smaller rivals.
It called for improved training of pilots and inspectors, and better cockpit design, among 25 recommendations to prevent a repeat of the catastrophe.
The report also found that the A330's speed sensors, known as pitot tubes and designed by France's Thales, were only upgraded after the disaster, even though there had been previous incidents with the equipment.
It urged a review of aircraft stall warning systems following criticism of the alarm's erratic behaviour when the plane was deep into its 38,000-foot plunge.
Families of crash victims immediately criticised the report as too soft on the aerospace industry.
A lawyer for families of some of the victims said that to deny the extremely significant influence of technical defects is to go into denial about the reality of the accident.
