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Old 22nd Feb 2017, 03:09
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_Phoenix
 
Join Date: Jan 2015
Location: Near St Lawrence River
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On the contrary, Airbus does everything in its power to help airplanes keep their normal flight laws and associated protections.
There was "alternate 2B law", the roll is direct but pitch is still a g load factor law or "normal'' but no stall protection.
After autopilot disconnect, the aircraft banked to the right and lost in altitude. Then possible Bonin grabbed the sidestick instinctively from a reclined seating position. The "normal" flying technique (mayonnaise stirring) put him quickly into PIO with large lateral inputs and an average(30%) nose up. It took about 10 seconds to stabilize laterally, but meanwhile the aircraft changed flight path from horizontal to climb. During next 30 seconds, before stall warning blared into cockpit, the pitch input averaged around neutral = "0" change in flight path (climbing). Now, here is the catch -> Low Energy Awareness: "Past experience on airplanes fitted with a flight-control system providing neutral longitudinal stability shows insufficient feedback cues to the pilot of excursion below normal operational speeds. The maximum-angle-of-attack protection system limits the airplane angle of attack and prevents stall during normal operating speeds, but this system is not sufficient to prevent stall at low-speed excursions below normal operational speeds. Until intervention, the pilot has no stability cues because the aircraft remains trimmed"
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