OPERATIONAL PHILOSOPHY
AP / FD / ATHR
A318/A319/A320/A321
FLIGHT CREW TRAINING MANUAL
recommended technique to set A/THR to off
2) THRUST LEVERS SET TO IDLE
If thrust levers are set to IDLE, A/THR is set to off. This technique is usually used in descent, when the A/THR is in THR IDLE, or at landing. During flare, with the A/THR active, the thrust levers are set to the CLB detent. Then, when thrust reduction is required for landing, the thrust levers should be moved rapidly and set to the IDLE stop. This will retard thrust, and set A/THR to off. As a reminder, the "RETARD" aural alert will sound. In flare, this aural alert will occur at 20 ft, except in the case of autoland, where it occurs at 10 ft.
It should be noted that, when the thrust levers are set back to IDLE and A/THR set to off: The A/THR can be reactivated by pressing the pushbutton on the FCU, and returning the thrust levers
to the applicable detent. The thrust levers should be immediately returned to the applicable detent, in order to avoid flashing CLB or LVR CLB message on the first FMA column.
3) USE OF THE FCU PUSHBUTTON
Use of the FCU pushbutton is considered to be an involuntary A/THR off command (e.g. in the case of a failure). When pressed, thrust is frozen and remains locked at the value it had when the flight crew pressed the A/THR pushbutton, as long as the thrust levers remain in the CLB or MCT detent.
If thrust levers are out of detent, thrust is manually controlled and, therefore, unlocked. A THR LK message appears in amber on the FMA
In this case, when the flight crew moves the thrust levers out of detent, full manual control is recovered, and the THR LK message disappears from the FMA.
This feature should not be used, unless the instinctive disconnect pushbuttons are inoperative.
ALPHA FLOOR
When the aircraft's angle-of-attack goes beyond the ALPHA FLOOR threshold, this means that the aircraft has decelerated significantly (below ALPHA PROT speed): A/THR activates automatically and orders TOGA thrust, regardless of the thrust lever position.
The example below illustrates that:
? The aircraft is in descent with the thrust levers manually set to IDLE.
? The aircraft decelerates, during manual flight with the FD off, as indicated on the FMA.
OPERATIONAL PHILOSOPHY
AP / FD / ATHR
A318/A319/A320/A321
FLIGHT CREW TRAINING MANUAL
Speed scale and FMA indication in a typical A Floor Case 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A318/A319/A320/A321 机组训练手册 FCTM Flight Crew Training Manual(23)
