As the flight mode is always aiming to achieve the selected flight path, avoid the temptation to over-control. The recommended method to avoid over-controlling is to make a small sidestick input, hold for a short period and then return the sidestick to neutral. Even in turbulent conditions, the control law resists the disturbances well without pilot inputs. The pilot should try to limit his control inputs to that necessary to correct the flight path trajectory and leave the task of countering air disturbances to the flight control system. If the pilot senses an over-control, the sidestick should be released.
In climb, cruise, descent and approach, all these basic rules remain in effect.
2.60.4
A330/A340 General Information REV 1 (6 JUN 05)
FCTM Flight Controls
Flare.Mode
To perform the flare and landing, the flight controls need to be responsive and linear. Therefore on reaching 100 ft on the approach the pitch law is modified to be a full authority direct law with no auto-trim. A nose down term is introduced which requires the pilot to maintain a backpressure on the sidestick to achieve a progressive flare, as in a conventional aircraft. After touchdown, the control law progressively reverts to ground mode.
Protections
Normal Law provides five different protections:
.
High Angle of Attack Protection
.
Load Factor Protection
.
High Pitch Attitude Protection
.
High Speed Protection
.
Bank Angle Protection
The protections are complementary and together work to maintain the aircraft in the safe flight envelope. If an extreme manoeuvre is required, the pilot can make full sidestick inputs in normal law at any speed. This normal law protection does not apply to the rudder as it is not normally used in symmetrical flight.
However, it is important to remember that the normal flight envelope is defined as VLS to VMO/MMO. Pilots should not deliberately fly at a speed outside of the normal envelope unless absolutely necessary for operational reasons.
High.Angle.Of.Attack.Protection
The high angle of attack (AOA) protection allows the pilot to consistently achieve the best lift while preventing the aircraft from stalling.
The following description illustrates a sequence of events that would lead to the activation of the various stages of high AOA protection.
In level flight, if the A/THR is disengaged and thrust set to idle, the aircraft decelerates until the auto-trim stops. This occurs at a predetermined angle of attack called Alpha Prot. The speed that equates to Alpha Prot (V. PROT) is displayed as the top of a black and amber strip on the PFD speed scale. If no input is made on the sidestick, the aircraft will descend to maintain its current AOA (V. PROT). To maintain the flight path, the pilot must increase the backpressure on the sidestick, which also provides a tactile indication that auto-trim has stopped. At V. PROT, AOA protection becomes active and, if the sidestick is released to neutral and no thrust applied, the aircraft will gently descend maintaining V. PROT. When AOA protection is active, the speed brakes retract automatically, if previously extended, and the bank angle limit is reduced from 67° to 45°.
Flight Controls
FCTM REV 1 (6 JUN 05)
If the pilot maintains the backpressure, Alpha Floor (covered below) will activate. If the pilot disconnects the A/THR while maintaining full back stick, Alpha Max may be reached. The speed which equates to Alpha Max (V. MAX) is displayed as the top of the red strip on the PFD speed scale. Alpha Max is close to, but short of the 1g stall. When flying at V. MAX, the pilot can make gentle turns if necessary. In turbulence, airspeed may fall temporarily below V. MAX without significant effect. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A330/A340 机组训练手册 FCTM Flight Crew Training Manual(11)
