Commercial and Business Aviation Advisory Circular (CBAAC) No. 0206


No. 0206


Structural Overload in Transport Category Aeroplanes Caused by Rudder Inputs


This Commercial and Business Aviation Advisory Circular (CBAAC) is intended to bring to the attention of air operators, private operators and their pilots, the possibility of exceeding the structural capabilities of the aircraft, when full opposite rudder inputs are applied at speeds even below the design manoeuvring speed.


This safety issue was identified in connection with the U.S. National Transportation Safety Board's (NTSB) ongoing investigation of the November 12, 2001 accident involving American Airlines Flight 587, an Airbus Industry A300-600. Flight 587 was destroyed, when it crashed into a residential area shortly after take-off from John F. Kennedy International Airport (JFK), New York. Before impact, the vertical stabilizer and rudder had separated from the fuselage. The NTSB has learned that sequential full opposite rudder inputs (sometimes referred to as rudder reversals), even at speeds below the design manoeuvring speed, may result in structural loads that exceed those addressed by the certification requirements.


The NTSB Safety Recommendation A-02-01 and -02, dated February 8, 2002, original Signed by Marion C. Blakey, Chairman describes in more detail the safety issue identified and recommends appropriate pilot training programs be established and implemented for avoidance of dangerous combinations of sideslip angle and rudder position. Transport Canada recommends that operators disseminate this information to pilots for awareness, and where appropriate, establish suitable pilot training programs to avoid this hazardous condition.

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This NTSB safety recommendation is being endorsed by Transport Canada to ensure air operators, private operators and their pilots are aware of certain rudder inputs that may lead to structural failure of the aircraft. This initial action is being taken in advance of any further substantive action by Transport Canada, pending the outcome of the NTSB investigation.


Michel Gaudreau
Acting Director
Commercial & Business Aviation

Commercial & Business Aviation Advisory Circulars (CBAAC) are intended to provide information and guidance regarding operational matters. A CBAAC may describe an acceptable, but not the only, means of demonstrating compliance with existing regulations. CBAACs in and of themselves do not change, create any additional, authorize changes in, or permit deviations from regulatory requirements.