Originally Posted by PJ2
Thought I'd say hi.
Hi PJ2, Thank you for confirming my understanding of 'Bus roll control response, and refuting my understanding that a pulsing technique was the norm with the Airbus. I guess a lot of these videos by Airbus crew are demonstrating an incorrect technique in hand flying. Looks like there is need for improvement.
Originally Posted by PJ2
The roll is sensitive in Direct Law and, with mis-handling, (or more bluntly, ham-fistedness), prone to PIO but I hasten to add that it is readily controllable, (positive, not neutral stability). Letting go the stick would be a good first response to any PIO in roll,
The BEA third interim report data clearly indicates that Bonin set up a roll oscillation (or rather a series of them) immediately upon taking control. He did not stop making inputs to regain control, but instead accelerated his inputs to "get ahead" of the oscillation which he eventually did. This is the period that the aircraft started going for the Moon. It is likely that a pilot encountering roll PIO would face an extremely high workload during the oscillations and would also have his faith in the correct functioning of the controls shaken.
It seems clear that he had not received training in manual flight at altitude in either Normal or Alt 2 law, but also, he had not been properly trained to recognize/avoid and stop a PIO. (Or a stall for that matter.
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How many present line pilots have received any formal training with regard to PIO causes and correction? There may be yet more lessons we need to take away from the AF447 accident.