Thoughts on A300-600 rudder travel limiting system:
A very sticky situation for all involved. This wasn't merely a potential design flaw slipping thru the cracks or an unforeseen failure mode but a system that obviously should never have been approved by the regulatory authorities for its obvious undesireable characteristics.
This rudder travel limiting system increases yaw axis sensitivity with increasing indicated airspeed. The faster you fly, the pedal travel is progressively restricted until only about 1 inch of movement is possible (from approx 4" unrestricted). But this 1 inch is equivalent to other types such as the 747 - 767 depressing the pedal all the way to the floor.
If this was a pilot induced situation but hypothetically an aircraft equipped with a ratio changer limiting system, do you feel the pedal would intentionally be pushed to the floor, repetitively?
In addition, the rudder pedal breakout force is very close to the force required to move the rudder pedal 1 inch (full rudder for that airspeed). In other words, the pedals are extremely light at high airspeeds
My experience with the A300-600 indicates the yaw damp and or pitch trim paddle/s not engaging is not an uncommon problem. The instinctive reaction by many when the paddle drops off or does not initially engage and latch (during pre-flight cockpit setup)is to immediately reengage the paddle. This often begins the sequence of trying to engage, won't engage, try again, fails again, etc...call maintenance. When maint. arrives, usually the paddle will engage. Why? If the paddle doesn't initially engage, the FAC (flight augmentation computer)requires approx 5 minutes to accomplish & pass an internal self test or safety check. If the paddle is reengaged before the 5 minute test is complete, the paddle will again drop off and the process (and clock) start all over. If mx arrives 5 minutes later, usually the problem resolves itself.
Also, #2 yaw damp is sort of the back-up yaw damp channel with the #1 directly controlling the rudder.