Originally posted by Schwartz
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What concerns me here is improper use of rudder, in reversals, doublets, whatever you prefer to call them.
Why?
Because they are unnecessary and unsuited to large transport aircraft and tend to result in pilot-induced occillations, overcontrol, overswing and, yes, structural failure.
Because when a pilot uses aggressive rudder like this it is an indication of either a) panic and bad instincts, b) improper training and understanding of rudder on large transport aircraft and/or c) aircraft-pilot coupling resulting from a triggering event, in this case a sudden wind shear. gust, call it what you will.
Because the pilot who broke AA587 and killed everyone on board had also displayed such behavior of several occasions prior to that crash and nobody took it too seriously.
Because since then EVERY pilot should understand the SIMPLE FACT that rudder on these aircraft is not intended, nor designed, to be used in this manner. It is there for steady state inputs to compensate for crosswinds and engine failure and occasionally for very careful manuevering.
Never for roll, unless in a very high AoA where ailerons are no longer effective, because phase lag leads to PIO and overcontrol and structural failure...
Not needed for torque compensation or turn coordination. Not a Cessna.
Never used in large alternating reversals as seen here.
Not a wise alternative to go-around when roll alone cannot align you with the runway, for reasons that this video makes painfully obvious.
Because what a pilot displays a methodology involving rudder reversals in a situation like this (which is not structurally dangerous to the fin) there is a good chance that it may be repeated at higher speeds, perhaps in wake turbulence, where it is structurally dangerous, in an aircraft with 400+ souls on board.
Essentially, and for all the above reasons, because it is alarming pilot behavior.
The non-FBW A300 has a rudder travel limiter. All modern transport aircraft limit rudder deflection as airspeed increases. It is not exclusively a FBW thing. It won't save the structure from deliberate abuse however...
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