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Old 18th Dec 2015, 16:33
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FDMII
 
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_Phoenix;

I'm sure what is said below will be familiar to you - just reiterating some of the characteristics of the Airbus system for the discussion. I don't intend here to be pedantic or instructive.

With that in mind..., "manual flying" has been an illusion for over fifty years.

The DC8 ailerons and rudder were hydraulically-powered with spring-tab backup while the elevator was cable-pulley & tab. Boeing had introduced hydraulic flight controls on the B707 in the late-50's.

Back then, it was fluid that sent the impulses - today it's electrons. Springs on control column/control wheel circuits & mechanisms provided feedback to the pilot.

The AB SS provides such feedback by the same method, (springs), so doing steep turns, for example, in either Normal, Alternate or Direct laws, the stick has to be held back more firmly when the bank angle is exceeds 33°.

What may be confusing to some, particularly when discussing the Airbus, is the difference between C* laws in FBW systems, and the various protections that may be built into EFCS systems. FBW in and of itself, offers no "protections"; FBW is just another way of moving flight control surfaces. "Protections" are possible because the system is digital and as we all know, anything that can be imagined can also be done with digital signals.

The rudder pedals have been, and should absolutely continue to be a footrest except in the usual circumstances with which pilots are familiar - crosswind landings and engine-out yaw control.

You do not need, "superman to fly the alternate laws", (an exaggeration I'm sure). What you actually need is a thorough understanding of the airplane and that comes, as always, with training, experience and continuous learning through staying in the books, (which is something I really wonder about in today's pilots, who seem to be discouraged by managements, (who are focussed entirely on slavishly following SOPs rather than encouraging airmanship and thinking), from deepening their knowledge of systems, high-altitude, high-speed, swept-wing flight by study, and reading accident reports.

Alternate Law circumstances are regularly-trained in the sim as a result of system failures which are in the script. Alternate law is a non-event; the airplane is conventional in the sense that one just flies the airplane normally, including respecting the stall warning. When actually flying the airplane, the change in laws is essentially transparent to the pilot. The cautions (and therefore the responsibility for knowledge of one's airplane), are related to loss of protections, not to any "special handling" requirements due to FBW.

I don't think you can say that computers have transformed pilots into "idiots" any more than hydraulics have.

Even as technology is never neutral or innocent, it is, in my view, the abuse of the tools that has done so because airline managements began assuming that "these airplanes fly themselves", and so require/mandate that the autoflight systems be engaged as soon as possible after takeoff and remain engaged until the landing rollout is completed. Asian carriers monitor this with FDM, a wholly inappropriate abuse of a safety technology, so disconnecting and doing something with the airplane is both an institutionalized fear as well as a safety problem. A more irresponsible mandate on the part of an air carrier could not perhaps be conceived/implemented, but there it is - a growing generation of "pilots" who can't fly and who are increasingly afraid to try.

Last edited by FDMII; 18th Dec 2015 at 20:58.
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