AF447 an Air France Airbus A330-200, struck the mid Atlantic ocean just over a month ago ‘in flying position’ going straight ahead but falling so fast its underside was forced upwards toward the ceiling with ‘great compressive force’.

There was no mid air breakup.

The accident, which killed all 228 people on board the Rio de Janeiro to Paris flight on 1 June, when it was beyond radar 1500 kilometres from the Brazilian coast, is outlined in considerable detail in the preliminary report by the French air accident investigation authority the BEA released in Paris overnight.

Those details invalidate some earlier criticisms of the report, based on a televised press conference. The report has been also been released in English.

The flight path of AF447. (BEA)
The flight path of AF447. (BEA)

The investigation’s leader Alain Bouillard told the news conference that “Between the surface of the water and 35,000 feet, we don’t know what happened.

“In the absence of the flight recorders, it is extremely difficult to draw conclusions.”

However the preliminary report, made a day after the 30 day timeline required by international convention after a major air crash, says the jet didn’t break apart before it hit the sea, and appeared to have struck the water belly first after gathering speed while dropping thousands of feet through the air.

distortions

The report contains little new information yet Bouillard pointed out that none of the life vests recovered from the crash zone were inflated, suggesting the passengers had not been able in the circumstances to be prepared by cabin crew for a crash landing.

Although the inquiry has not received the results of autopsies carried out on the 51 bodies retrieved from the search zone it noted that they were well preserved and retained their clothing.

This is further evidence no mid air breakup with a consequent destructive air blast took place inside the Airbus.

While taking reporters through the preliminary report Bouillard said faulty air speed readings from the external air pressure pitots on the A330-200 were not the cause of the crash but had not been “excluded from the chain that led to the accident.”

Which on one reading means that the pitot manufacturer, Thales, and Air France which knew they were unsatisfactory, face some serious law suits in the future.

The report confirmed that one of the automated status messages sent from the flight to the operations centre in Paris indicated inconsistent speed data was coming from the pitots which could destabilise its control systems.

Faults in the pitots, including a susceptibility to icing, had lead Air France to decide in April to replace them with improved units as a matter of urgency but that work had only just started when AF447 crashed while crossing a notoriously stormy zone stretching from the tropics of South America to Africa.

The search for the two ‘black boxes’ carried by the jet, a cockpit voice recorder and a flight data recorder, has been extended to 10 July, even though the locational beacons fitted to them should have run out of power by now.

Without them, the riddle as to why this particular flight, experiencing faulty air speed indications amid known turbulent and potentially ice forming conditions should have ended in disaster when so many others have not will go unanswered.