OPERATIONAL PHILOSOPHY
AP / FD / ATHR
A318/A319/A320/A321
FLIGHT CREW TRAINING MANUAL
An ECAM caution and an FMA message trigger during thrust lock:
‐ THR LK appears in amber on the FMA
‐ The ECAM caution is:
AUTOFLT: A/THR OFF THR MOVE LEVERS
ENG: THRUST LOCKED THR MOVE LEVERS
In this case, when the flight crew moves the thrust levers out of detent, full manual control is recovered, and the THRUST LOCKED 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.
Speed scale and FMA indications in a typical A floor case
When the speed decreases, so that the angle-of-attack reaches the ALPHA FLOOR threshold, A/THR activates and orders TOGA thrust, despite the fact that the thrust levers are at IDLE.
When the aircraft accelerates again, the angle-of-attack drops below the ALPHA FLOOR threshold.
TOGA thrust is maintained or locked. This enables the flight crew to reduce thrust, as necessary. TOGA LK appears on the FMA to indicate that TOGA thrust is locked. The desired thrust can only be recovered by setting A/THR to off, with the instinctive disconnect pushbutton.
ALPHA floor is available, when the flight controls are in NORMAL LAW, from liftoff to 100 ft RA at landing. It is inhibited in some cases of engine failure.
A/THR USE - SUMMARY
Use of A/THR is recommended during the entire flight.
OPERATIONAL PHILOSOPHY
AP / FD / ATHR
A318/A319/A320/A321
FLIGHT CREW TRAINING MANUAL
It may be used in most failures cases, including: 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(26)