Riporto da Airbus FCTM:
OPERATIONAL RECOMMENDATIONS
In order to avoid exceeding structural loads on the rudder and vertical stabilizer, the following recommendations must be observed.
THE RUDDER IS DESIGNED TO CONTROL THE AIRCRAFT, IN THE FOLLOWING SITUATIONS
A. In normal Operations, For lateral control
- During takeoff roll, when on ground, particularly in crosswind conditions
- During landing flare with crosswind, for decrab purposes
- During the landing roll, when on the ground.
In the above situations, large and even rapid rudder inputs may be necessary in order to
maintain control of the aircraft.
The flight crew should always apply the rudder corrections as necessary, in order to obtain the appropriate aircraft response.
On Airbus aircraft, the rudder control system includes a turn coordination function to achieve acceptable turn coordination,.
B. To counteract thrust asymmetry
Up to full rudder deflection can be used to compensate for the yawing moments that are due to asymmetric thrust.
Note: At high speed (i.e. slats retracted), thrust asymmetry (eg. due to an engine failure) does not have a significant effect on the yaw control of the aircraft. The rudder deflection required to counter an engine failure and center the sideslip is small.
C. In some other abnormal situations
The flight crew may also use the rudder pedals in some abnormal situations. For example:
- Loss of both yaw damper systems. The flight crew uses the rudder pedals as deemed
necessary, for turn coordination to prevent excessive sideslip.
- Rudder trim runaway. The flight crew uses the rudder pedals in order to return the rudder to neutral
- Landing with an abnormal landing gear position: The flight crew uses the rudder pedals for directional control on the ground.
In all of the normal or abnormal situations that are described above, correct rudder pedals use does not affect the structural integrity of the aircraft.
Note: In the event of a rudder travel limit system failure, refer to the relevant RUDDER
TRAVEL LIMIT FAULT procedure.
THE RUDDER SHOULD NOT BE USED
- To induce roll
- To counter roll, induced by any type of turbulence.
Regardless of the airborne flight condition, aggressive, full or nearly full, opposite rudder pedal inputs must not be applied. Such inputs can lead to loads higher than the limit, and can result in structural damage or failure. The rudder travel limiter system is not designed to prevent structural damage or failure in the event of such rudder system inputs.
Note: The Operator policy must never include rudder pedal reversions. This restriction also applies to the so-called "aircraft defensive maneuvers" in order to disable or incapacitate
hijackers.
For dutch roll, the flight control laws combined with the neutral aircraft damping are sufficient to correctly damp the dutch roll oscillations. Therefore, the flight crew should not use the rudder pedals in order to complement the flight control laws.
SPECIFIC CASES: USE OF THE RUDDER DURING UPSET RECOVERY
The Airbus training program emphasizes the correct use of the rudder, particularly during maneuvers that are performed in order to recover upset. The industry-produced "AIRPLANE UPSET RECOVERY TRAINING AID" supports this training program.
Credo che l'ultimo capoverso fu introdotto a seguito delle raccomandazione NTSB.