Air France Rio crash: Black box recorder data 'intact'

[FULLTHRUST]

AF447 crew not trained for high-altitude stall: investigators

http://www.flightglobal.com/articles/20 ... ators.html

Inquiries into the loss of Air France flight AF447 have yet to explain fully why the pilots failed to avert the Airbus A330's fatal stall, despite its onset being characterised by buffet and the activation of a stall warning.

But the AF447 investigation has said that the two pilots had not received any high-altitude training for unreliable airspeed procedures and manual aircraft handling. It is formally recommending review of training and check programmes, and crucially the mandatory creation of specific exercises for manual handling, including stall recovery.



Airbus clashes with pilots over AF447 alarm

http://www.flightglobal.com/articles/20 ... alarm.html

While the airframer has formally said little about the latest findings by the French Bureau d'Enquetes et d'Analyses, a clear rift has emerged over the human factor aspect of the accident.

"The situation was not ambiguous and the stall was obvious," said a source at the airframer, pointing out the 54s continuous vocal alarm which sounded as the aircraft climbed to about 37,500ft and the flying pilot kept his sidestick nose-up.

As the stall worsened, the aircraft's airspeed bled away and it began to descend, the angle of attack increasing to 41.5° before the airspeed fell below 60kt and the angle of attack became "non-computed data" - an invalidation which shut off the stall alarm.

In the 75s following the shut-off, however, the stall warning sounded another eight times as the angle of attack data briefly became valid again, each time at values from 38-43°, as the airspeed fluctuated with the aircraft's attitude.

Four of those eight warnings occurred while the flying pilot was holding the sidestick fully back, with no indication from the flight-data recorder of a relaxation in response to the alarm.

Another two instances occurred while the pilot made inputs "apparently not related to the alarm", said the source, while the other two occurred when the pilot's actions were "possibly consistent" with the stall alarm switching off and on.

"We are not in a situation where the crew has a systematic and consistent reaction to the stall warning," the source added.

"It is crucial that a crew reacts immediately to the stall warning, in order never to get into such a situation. Airliners are not to be flown at such angles of attack - what happened beyond [the initial continuous alarm cut-off] is clearly far out of the flight envelope. None of our test pilots ever went into such a situation."


Stall warning controversy haunts AF447 inquiry

http://www.flightglobal.com/articles/20 ... quiry.html

French investigation agency Bureau d'Enquetes et d'Analyses withdrew a safety recommendation on the stall warning before publishing its latest interim report into the accident, stating it was "premature". But the decision generated suspicion, with French cockpit union SNPL demanding an explanation and threatening to withdraw assistance until it could be assured the BEA was not simply setting up the crew as scapegoats.

The BEA has determined that the crew had not been trained to handle a high-altitude loss of airspeed data and risk of stall, and a partial transcript detailed the confusion in the cockpit over the twinjet's behaviour.

Detailed recorder traces from AF447 show that the aircraft's elevators remained at pitch-up throughout the final 3min of the 1 June 2009 flight, never falling below 15°, in line with primarily nose-up inputs from the flying pilot - despite automated voice warnings that the jet was stalling.

Movements of the elevators and the trimmable horizontal stabiliser, which adjusted to the fully-up position in response to the A330's angle of attack, were "consistent with the pilot's inputs" throughout the flight, said the BEA.

While the stall alarm sounded continuously for 54s the captain, urgently called back from a rest break, re-entered the cockpit just as it ceased. The warnings then became intermittent, owing to A330 logic that cuts out the alarm if airspeeds become invalid.

The cockpit transcript shows the captain asked the crew what they were doing, to which the non-flying pilot responded: "What's happening? I don't know what's happening."...................Fullthrust comment....>>>> As a trained pilot on type you should know what's happening

BEA said its recommendation focused on functioning of the stall warning in extreme angles of attack, one which is "never encountered in flight tests, or even considered". It added that a human factors working group will analyse why the stall warning on AF447 sounded continuously "without provoking any appropriate reaction from the crew".


AF447's initial altitude drift went virtually unchallenged

http://www.flightglobal.com/articles/20 ... enged.html

The co-pilot took manual control but BEA says he made "rapid and high-amplitude" movements on the sidestick, which were "almost stop to stop", as well as a nose-up input which increased the A330's pitch to 11° in 10s.

While the autothrust disconnection had resulted in the thrust being locked, at 83% of N1, this automatic locking was deactivated 15s later. But the thrust levers were still positioned in the 'CL' detent, the normal setting for cruise. With the A330 under manual control the engines responded by powering up to 104% of N1.