35. Engines / Thrust Levers (Power Plant/ Auto Flight) [B] Flashcards
What controls the engines in all operating regimes?
FADECs (Full Authority Digital Engine Controls)
What is the power source for the FADEC?
• The system has its own alternator making it independent of the aircraft electrical system when N2 is above10%
• If this alternator fails, the FADEC automatically switches to aircraft electrical power
The FADEC detects a fault during automatic start. What crew intervention is required?
There is no crew intervention necessary. The FADEC will discontinue the start, dry crank to clear the fuel from the engine, and attempt a restart (if warranted) automatically.
How many igniters fire during a normal automatic ground start sequence?
• One igniter with the other serving as a backup
• The FADEC automatically alternates the igniters (A or B) at each start
How many igniters fire on manual or in-flight starts?
• Two, both A and B
On the ground, how can the A/THR be armed?
• By setting the thrust levers in the TOGA or FLEX gate (with a FLEX temperature inserted in the MCDU)
• At least one FD must be ON for A/THR to arm during takeoff
What is the active range of the A/THR?
• Just above IDLE to the CL detent (2 engines)
• Just above IDLE to the MCT detent (1 engine
What determines the maximum thrust the A/THR system will be able to command?
The thrust lever angle
What are three ways to disconnect the A/THR?
• A/THR pushbutton
• Instinctive disconnect pushbuttons
• Thrust levers to IDLE
What is the proper method of disconnecting A/THR?
Set the thrust lever angle to the existing EPR and push the instinctive disconnect pushbuttons
How would the A/THR be disconnected for the remainder of the flight?
Press and hold the instinctive disconnect pushbutton for 15 seconds. The A/THR cannot be re-engaged once this is done. ALPHA FLOOR is also lost if this is done
What happens to thrust and what annunciates on the FMA during ALPHA FLOOR?
• Thrust – TOGA
• FMA – “A.FLOOR”
When does the aircraft leave ALPHA FLOOR and what does the FMA change to?
Upon reaching a lower angle of attack. The FMA changes to “TOGA LK”
What should the pilot do to get out of TOGA LOCK?
• Push the instinctive disconnect pushbuttons and move the THRUST LEVERS to the CL detent, if not already in the climb detent
• Afterwards re-engage the autothrust
When will ALPHA FLOOR activate?
When the aircraft reaches a high AOA
When will Thrust Lock occur?
- Thrust levers in CL detent and A/THR pushbutton on the FCU is pushed, or
- A/THR disconnects due to a failure
How is A/THR normally armed?
By advancing the thrust levers to TOGA or FLX
What would be the normal FMA indications during a takeoff roll using FLEX thrust on a RWY with a localizer?
MAN FLX, SRS, RWY, A/THR (blue)
What would the FMA indications be during a takeoff roll using TOGA thrust on a runway without a localizer?
MAN TOGA, SRS, A/THR (blue)
What would the FMA indications be during takeoff roll if the A/THR didn’t arm on a runway with a localizer? Should the takeoff be aborted?
• SRS, RWY
• Continuing the takeoff is a safe option, but the thrust levers must be moved to the climb detent at thrust reduction altitude and the crew must manually engage A/THR
How should A/THR be turned off?
Match the blue thrust lever angle indicators to the present thrust setting on the EWD and push the instinctive disconnect pushbuttons or move THRUST LEVERS to IDLE
What should the pilot do to get out of THRUST LOCK?
Move it out of the climb detent
What controls the engine LP fuel valves?
• Engine MASTER switch
• ENGINE FIRE pushbutton
What does a FAULT light on the ENG panel indicate?
• The position of the HP fuel shut off valve is abnormal, or
• Automatic start sequence of the associated engine aborts, or
• There is a malfunction of the thrust control
