Rudder travel limiter

A rudder travel limiter, or rudder limiter, is a controlling device in an aircraft used to mechanically limit the maximum rudder deflection.

The rudder travel limiter in the Airbus A300-600 is controlled by the Feel and Limitation Computers (FLC) maintaining sufficient yaw control within the entire flight envelope and limiting excessive lateral loads on the rudder and vertical stabilizer.

Faults with rudder travel limiters were involved in the crashes of Indonesia AirAsia Flight 8501 and American Airlines Flight 587. After the latter crash Airbus changed the rudder travel limiter on the Airbus A300-600 from a variable ratio design to a variable stop design, as the latter is less complex, with less severe failure modes.

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