PPRuNe Forums - View Single Post - AF 447 Thread No. 9
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Old 13th Jul 2012, 14:27
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HazelNuts39
 
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Originally Posted by DozyWannabe
(...) the pusher has moved into history across the industry. The FBW designs from both major manufacturers, rather than providing automatic stall recovery, instead try to prevent the aircraft from approaching stall in the first place, whether via hard protections in the case of Airbus, or by increasing opposing yoke force in the case of Boeing - and as I said above, the aircraft are designed to naturally nose-down at the stall.
The rules haven't changed, so an airplane that doesn't meet the stall characteristics requirements without a stick pusher will still need one. What you have written applies to FBW airplanes. The FBW system permits modification of the natural characteristics of the airplane so that it meets the requirements. The Final Report describes the type certification in section 1.18.1.

While the airplane flight control system is designed so that, in normal law, the pilot or the A/P cannot command an AoA greater than alphamax, and therefore cannot stall the airplane in the 'usual' way, the system apparently can provide a powerful nose-down pitch very similar to a stick pusher if alphamax is exceeded in any other way.
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