By Peter Allen
-Pilot was on a break when trouble started and never made it back to his seat
-Two co-pilots battled to keep Flight 447 in the air as it stalled and plummeted into the Atlantic Ocean
Terrifying: Analysis of the black box flight recorders recovered from Air France flight 447 found it plunged for four minutes before crashing into the Atlantic Ocean
Hundreds of passengers on board an Air France jet endured a three-and-a-half minute plunge to their deaths after it stalled while the pilot was resting, it emerged today.
The terrifying end of Flight 447 came after it malfunctioned in a heavy storm en route from Rio de Janeiro to Paris two years ago.
All 228 people from 32 nations, including five Britons and two Americans, died after it hit the Atlantic at a speed of 180 feet a second.
Details of the worst crash in Air France's history emerged in Paris where experts have analysed data from the plane's recently retrieved black box flight recorders.
Aviation industry sources said pilots appeared to have acted contrary to normal procedures in raising, rather than lowering, its nose in response to an alert that the plane was about to lose lift or, in technical parlance, 'stall'.
An aerodynamic stall is a loss of lift due to a high angle of attack, or angle between the plane and airflow. Pushing the control stick forward and lowering the nose adjusts for this.
It does not refer to a stall of the engines, which the BEA said had operated and responded throughout to crew actions.
The 2009 emergency began with a stall warning two and a half hours into the Rio-Paris flight and nine minutes after the captain had left the cockpit for a rest period.
Shortly before, a junior pilot had told flight attendants to prepare for a 'little bit of turbulence'
The Airbus A330 jet climbed to 38,000 feet and then began a dramatic, rolling from left to right, with the youngest of three pilots handing control to the second most senior pilot one minute before the crash.
The time-line was described in a note by France's BEA crash investigation authority, which said it was too early to give the causes of the crash ahead of a fuller report in the summer.
'These are so far just observations, not an understanding of the events,' BEA director Jean-Paul Troadec said.
The captain Marc Dubois had been taking a break, four hours into the flight when a co-pilot, 32, reported heavy turbulence, announcing the problem to crew and getting passengers to fasten seat-belts. Another co-pilot, aged 37, was also assisting.
Mr Dubois returned after 'several attempts' to call him back to the cockpit but was not at the controls in the final moments, according to information gleaned from black boxes.
Agony: Friends and relatives of the Air France flight 447 passengers comfort each other after attending a mass at the Candelaria Cathedral in June 2009
Grief-stricken: People from 32 nations including five Britons and two Americans were killed when the plane went down while flying over the Atlantic Ocean
By the time the 58-year-old returned, just over a minute into the emergency, the aircraft was plunging at 10,000 feet-a-minute with its nose pointing up 15 degrees and at too high an angle compared to the onrushing air to provide lift.
Recorded conversations also show that he never actually returned to his seat, or took over the controls - instead leaving the flying to his assistants.
He had clocked up 11,000 flying hours over his airline career, while his more junior counterparts had 6,500 and 2,900 hours respectively.
The co-pilot tried to fly above the storm, but instead the plane began plunging seawards, with its nose pointed up at about 15 degrees, while rolling from left to right.
By this time an alarm was sounding because of the stall, with the co-pilot announcing that the aircraft was at an altitude of just 10,000 feet.
The BEA said the reading of the black boxes suggested the crew were not able to determine how fast the plane was flying.
That echoes earlier findings which suggest the pitot tubes or speed sensors on the plane may have become iced up.
Information from black boxes hauled up from the Atlantic floor earlier this month was still incomplete.
The airline said in a statement that the crew had demonstrated a 'totally professional attitude'. France's pilots union declined to comment.
'It's very emotional to see the unrolling minute by minute or second by second at some points of what happened,' said John Clemes, vice president of the families' support group.
Search: Two Hercules C-130 crew members from the Brazilian Air Force search for remains
Recovered: A sealed flight data recorder from the Air France flight
'You automatically think of your family member and how they were living through this. It's the events that caused the deaths of 228 people so it's traumatic and moving.
France's BEA crash investigation agency said pilots pulled the nose up at crucial moments as the aircraft became unstable and the aircraft generated an audible stall warning.
'The inputs made by the pilot flying were mainly nose-up,' the BEA said in a time-line based on initial examination of the cockpit voice and data recorders.
A top aircraft industry safety consultant said the standard guidance in the Airbus pilot manual called for the pilot to push the control stick forward to force the plane's nose down in the event of a stall, which can lead to a loss of control.
'The BEA is now going to have to analyse and get to bottom of how crew handled this event,' said Paul Hayes, safety director at Ascend Aviation, a UK-based aviation consultancy.
'The big question in my mind is why did the pilot flying (the aircraft) appear to continue to pull the nose up,' he said.
'I must stress we are commenting and speculating on preliminary factual information, which will need analysing.'
Horrific: The black box had lain 12,000ft below the Atlantic after the Air France jet sank
Details: The recordings revealed that two co-pilots were flying the plane when its engines cut out and desperately tried to keep it in the air
The BEA report was strictly factual and did not allocate any blame or cause of the crash on June 1, 2009.
'These are so far just observations, not an understanding of the events,' BEA director Jean-Paul Troadec told reporters.
In a passage likely to attract scrutiny, the BEA said the pilot 'maintained nose-up inputs' when a fresh stall warning went off 46 seconds after the autopilot disengaged itself.
The BEA declined to say whether this was the correct action to take and the information given so far does not give a complete picture of the information displayed to the crew.
But the response contrasts with the latest advice to pilots contained in an Airbus training seminar in October last year, according to a document obtained by Reuters.
In large red capital letters, the document says that in the event of a stall warning, pilots should 'APPLY NOSE DOWN PITCH CONTROL TO REDUCE AOA (ANGLE OF ATTACK)'.
Orthodontist Jose Rommel Souza who worked at the Reading Orthodontic Centre was listed among the 228 passengers on the jet
Two aviation industry sources said the drill in force at the time of the accident was to apply full thrust and reduce the pitch attitude of the aircraft, which means lowering the nose.
Later guidance calls for pilots to push the nose down and adjust thrust as necessary, they said, asking not to be named.
The crew's response will be added to what is already known about probable icing of the aircraft's speed sensors, which Air France identified as the most likely cause of the crash.
Airbus said the report upheld earlier evidence which was based on automated maintenance messages relayed from the plane.
The BEA dampened speculation that the jet may have been engulfed by a freak equatorial storm.
Pilots had decided without apparent stress to alter course slightly to avoid turbulence shortly beforehand. But the junior pilot told flight attendants to prepare for a 'little bit of turbulence'
'In two minutes we should enter an area where it'll move about more than at the moment; you should watch out,' he told cabin staff. 'I'll call you back as soon as we're out of it.'
source:dailymail
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