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Posted: 7/5/2012 10:02:58 AM EDT
[Last Edit: 7/5/2012 10:03:48 AM EDT by cobra-ak]
As I expectedOnly instrument rated pilots after instrument failure can tell you how hard you have to fight the seat of your pants feeling and vertigo to resist the temptation to aggravate a stall and enter the graveyard sprial. A dark night with no horizon only reinforces those doubts about which attitude and power setting will keep the shiny side up. Training with simulated failures in all attitudes and throttle if possible outside the simulator with a safety pilot for everyone's sake is needed.
Link Posted: 7/5/2012 5:51:54 PM EDT
[Last Edit: 7/5/2012 5:53:35 PM EDT by NimmerMehr]
I have no idea why Bonin decided to climb for 3 minutes..
Link Posted: 7/6/2012 3:34:43 AM EDT
If you want to read the full 200+ page report, look here:
http://www.bea.aero/en/enquetes/flight.af.447/rapport.final.en.php

You can also peruse the Flight Data Recorder readouts and the full transcript of the Cockpit Voice Recorder.

It appears that the pilots did not follow the "Unreliable Speed Indications" emergency procedures.  The report also indicates that this emergency procedure isn't presented that often in training.

A number of factors are believed to be related to why the pilots kept the aircraft nose up.
- It is possible they thought the aircraft may have been in an overspeed condition (based on statements recorded on the CVR)
- The stall recovery procedure immediately after takeoff involves keeping the nose at a 12-degree nose up attitude, and the pilot may have reverted to that thinking even though that approach doesn't work at high altitudes/airspeeds.
- The flight director on the primary flight display kept directing a nose up attitude; the emergency procedures specifically say to deactivate the flight director in the event of unreliable speed indications.

It also appears that the pilots ignored the repeated stall warnings, even though the stall detection system is linked to the AOA sensor and would be unaffected by a loss of the pitot-static system.
Link Posted: 7/6/2012 3:35:56 AM EDT
Originally Posted By NimmerMehr:
I have no idea why Bonin decided to climb for 3 minutes..
You have to fight the feeling, when there is no horizon and you get conflicting instruments or outright vacuum or electrical failure your body will play tricks on you, you think you are decending fast and then pull back on the yoke, making a stall where there is no windstream over the wings, just jet thrust, the plane goes into a graveyard spiral. The best training is under the hood where the safety pilot begins to simulate failures by covering instruments one at a time until you are just flying with compass and turn cooridnator. It is difficult you will be dizzy from the sensations of your body but you will fight the urge for a death grip on the yoke

Link Posted: 7/6/2012 4:55:02 PM EDT
Yeah, it's freaky.  I did some no-gyro ASR's in a sim, a while back.  That was...interesting.
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