Engine Thrust Levers

Question 1

What controls the engines in all operating regimes?

Answer 1

FADEC’s (Full Authority Digital Engine Controls)

Question 2

What functions does the FADEC control?

Answer 2

• Control of gas generator
• Protection against engine exceeding limits
• Power management
• Automatic engine start sequence
• Manual engine start sequence
• Thrust reverser control
• Fuel recirculation control

-Transmission of engine parameters and engine
monitoring information to cockpit indicators

• Detection, isolation, and recording of failures
• FADEC cooling

Question 3

What redundancy does the FADEC have?

Answer 3

Dual channel redundancy – one channel is active while the other is standby.

Question 4

What is the power source for the FADEC?

Answer 4

• The system has its own magnetic alternator making it independent of the aircraft electrical system

Question 5

When will the FADEC abort a start?

Answer 5

• Hot start
• Hung start
• A stall
• No light up

Question 6

If the FADEC detects a fault during automatic start, is any crew intervention required?

Answer 6

No. The FADEC will discontinue the start, clear the engine, and attempt a restart (if warranted)
automatically.

No. The FADEC runs an abort sequence if the start aborts on the ground:

• Close the HP valve
• Closes the start valve
• Turns off ignition
• Cranks the engine to clear fuel vapors
• Controls any additional start attempts

Question 7

When does the FADEC command a higher engine idle speed?

Answer 7

• Bleed system demands and ambient conditions (hot & high)
• Approach Idle (when FLAPS not at zero)
• Reverse Idle when on ground with thrust in REV IDLE position (slightly higher than forward idle)

Question 8

How many igniters fire during a Normal automatic ground start sequence?

Answer 8

• One igniter with the other serving as a backup

* The FADEC automatically alternates the igniters (A and B) at each start

Question 9

How many igniters fire on manual or In-flight starts?

Answer 9

Both A and B

Question 10

When does continuous ignition automatically operate?

Answer 10

• Engine flameout detection OR
• Engine running AND either:
• EIU failure
• Flameout detected
• Ignition delay during start

Question 11

What are the 6 detent positions of the thrust levers?

Answer 11

• TOGA
• FLX/MCT
• CL
• IDLE
• REV IDLE
• MAX REV

Question 12

On the ground, how do you arm the A/THR?

Answer 12

• 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

Question 13

What is the active range of the A/THR?

Answer 13

• IDLE to the CL detent (2 engines)

* IDLE to the MCT detent (1 engine)

Question 14

What is the normal operational position of the thrust levers when A/THR is active?

Answer 14

The CL detent

Question 15

What determines the maximum thrust the A/THR system will be able to command?

Answer 15

The position detent of the thrust lever

Question 16

What are 3 ways to disconnect the A/THR?

Answer 16

• A/THR pb
• Instinctive Disconnect buttons
• Thrust Levers to IDLE

Question 17

What is the preferred method of disconnecting A/THR?

Answer 17

Set the thrust levers to match the TLA to the existing N1 and disconnect using the instinctive disconnect pb.

Question 18

How do you disconnect the A/THR for the remainder of the flight?

Answer 18

Press and hold the Instinctive Disconnect button for 15 seconds.

Question 19

Will you be able to restore A/THR if disconnect buttons held for more than 15 seconds?

Answer 19

No

Question 20

What will you lose if you disconnect the ATHR by holding disconnect buttons for more than 15 seconds

Answer 20

Alpha Floor Protection

Question 21

What happens to thrust and what annunciates on the FMA when you reach Alpha Floor?

Answer 21

• Thrust – TOGA

* FMA – A.FLOOR

Question 22

What occurs during Alpha Floor protection after speed increases above VLS?

Answer 22

FMA changes to TOGA LK

Question 23

How do you then regain normal A/THR when in TOGA LK

Answer 23

• Move Thrust Levers to the TOGA detent
• Press the Instinctive Disconnect button
• Return Thrust Levers to CL detent
• Push the A/THR pb to engage A/THR

Question 24

When is Alpha Floor Protection active?

Answer 24

From lift-off through 100 feet RA on approach

Question 25

When would Thrust Lock occur?

Answer 25

• Thrust levers in CL detent and A/THR pb on the FCU is pushed, or
• A/THR disconnects due to a failure

Question 26

Explain the Normal start sequence.

Answer 26

• ENG MODE to IGN/START, FADEC is powered, ECAM displays ENG page (start valve +bleed
pressure), pack valve close
• ENG MASTER to ON,LP fuel valve opens, start valve opens, fuel used rest,N2 increases, oil
pressure increases
• N2 > 16% Ignition (A or B) on
• N2 > 22% HP fuel valve opens
• 15 seconds (MAX), EGT increase, N1 increase
• N2 > 50% start valve closes, igniter off
• Approximately 58% gray N2 background disappears
• Pack valve reopens with 30 sec delay (remains closed , if the other engine is started)

Question 27

Explain the Manual start sequence.

Answer 27

• ENG MODE to IGN/START, FADEC is powered, ECAM displays ENG page, pack valve closes
• ENG MAN START pb ON, start valve opens
• At maximum N2 motoring speed (min 20%), ENG MASTER ON
• Observe both A+B Ignition, LP and HP fuel valves open , fuel flow increase, EGT and N1 increase
in 15 seconds
• N2 > 50% start valve closes, igniters off
• ENG MAN START pb – OFF
• Pack valve reopens with 30 sec delay (remains closed , if the other engine is started)

Question 28

What controls the engine LP fuel valves?

Answer 28

• Engine MASTER switch

* ENGINE FIRE pb

Question 29

What does a fault light on the ENG panel indicate?

Answer 29

• Auto Start Abort

* Switch disagreement between HP valve and it’s commanded position