Engines (CFM)

Question 2

During engine start the amber FAULT light on the ENG MASTER panel goes on. This indicates…

Answer 2

A failure in the automatic start sequence.

Question 3

Can the engines be overboosted in the TOGA position?

Answer 3

No because the ECU provides engine protection limit by monitoring N1 N2 and HMU fuel flow adjustments.

Question 4

During normal operation at what detent are the thrust levers positioned once the thrust reduction altitude has been reached?

Answer 4

CL.

Question 5

During the automatic start sequence of ENG 2 you noticed that only igniter B is powered. Is this normal?

Answer 5

Yes igniters are used alternately for engine start.

Question 6

Continuous ignition is provided automatically when…

Answer 6

Engine flameout is detected and/or the EIU fails.

Question 7

When does the self powering of the FADEC start?

Answer 7

The FADEC system is self-powered above 58% N2.

Question 8

What is the main parameter to control the engine thrust?

Answer 8

N1.

Question 9

Where can you find the thrust reduction altitude and is the number always the same?

Answer 9

TAKE OFF PERF page of the MCDU (it can be modified).

Question 10

After take off the A/THR will not become active until…

Answer 10

The thrust levers are placed in the CLIMB position.

Question 11

What is required for the FADEC to compute a reduced thrust setting?

Answer 11

A FLEX temperature must be entered on the TAKE OFF PERF page of the MCDU.

Question 12

Holding the A/THR instinctive disconnect pushbutton’s for more than fifteen seconds will…

Answer 12

Disengage the A/THR (including Alpha Floor) for the remainder of the flight.

Question 13

When does the oil pressure indication turn into red?

Answer 13

The oil pressure indication turns red and a warning appears on ECAM when the oil pressure drops below 13psi.

Question 14

What is the purpose of the Hydromechanical Unit (HMU)?

Answer 14

The HMU controls fuel flow to the engine combustion chamber controls fuel hydraulic signals to actuators and protects against overspeeding.

Question 15

What is the function of the FADEC during a manual start?

Answer 15

Passive monitoring of the start sequence to close the start valve and cut off the ignition on the ground.

Question 16

When does oil quantity indication begin to pulse?

Answer 16

Decreasing below 5qts.

Question 17

A few seconds after selecting reverse the amber REV indication changes to green. What does this mean?

Answer 17

The reversers are now fully deployed.

Question 18

When does the oil quantity indication pulse?

Answer 18

The indication pulses when oil quantity goes below three quarts (decreasing) or above five quarts increasing.

Question 19

Which steps of a manual start are being taken care of by the FADEC?

Answer 19

Starter valve closure and ignition cut off.

Question 20

When does the oil pressure indication pulse?

Answer 20

The indication pulses when oil pressure exceeds 90psi (increasing) or 85psi (decreasing) or oil pressure drops below 16psi (drecreasing) or 20psi (increasing).

Question 21

You are about to take off. You have not inserted a FLEX temperature. Can you still take off?

Answer 21

Yes but only using the TO/GA detent.

Question 22

Which idle modes are available?

Answer 22

Modulated idle approach idle and reverse idle.

Question 23

During an engine start sequence the grey background on N2 disappears at about 57%. What does this indicate?

Answer 23

The start sequence has finished and all engine parameters have stabilized.

Question 24

What are the main components of the CFM 56-xx engine?

Answer 24

Low-pressure (LP) compressor/turbine high-pressure (HP) compressor/turbine combustion chamber and accessory gearbox.

Question 25

What controls the engines in all operating regimes?

Answer 25

FADECs (Full Authority Digital Engine Control)

Question 26

When would you use a manual start?

Answer 26

After aborting a start because of: - Engine Stall - Engine EGT overlimit - Low start air pressure When expecting a start abort because of: - Degraded bleed performance due to hot conditions or at high altitude airports - An engine with a reduced EGT margin in hot conditions or at a high altitude airport - Marginal performance of the external pneumatic power group

Question 27

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

Answer 27

- One igniter with the other serving as a backup | - The FADEC automatically alternates the igniters (A and B) at each start

Question 28

How many igniters fire on a manual or in-flight start?

Answer 28

Both A and B

Question 29

What control the engine LP fuel valves?

Answer 29

- Engine MASTER switch | - ENGINE FIRE pushbutton

Question 30

What functions does the FADEC control?

Answer 30

- Fuel metering - Engine limits based on thrust lever angle - Start sequencing - Provides engine indications and thrust limit displays on the E/WD

Question 31

What redundancy does the FADEC have?

Answer 31

Dual channel redundancy - one channel is active while the other is standby

Question 32

When will the FADEC abort a start?

Answer 32

- Hot Start - Stalled Start - No Ignition

Question 33

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

Answer 33

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

Question 34

When does the FADEC command a higher engine idle speed?

Answer 34

- Bleed Demands - Approach Configuration - High engine or IDG temperatures

Question 35

What are the primary differences between an automatic and manual start?

Answer 35

- Automatic Start: The FADEC provides full monitoring during start and will provide appropriate ECAM cautions and procedures to follow in the even of a start fault. - Manual Start: Automatic start interruption and auto-crank are not available

Question 36

What is the rated thrust of each engine?

Answer 36

- A319: 23,500 lbs | - A320: 27,000 lbs

Question 37

Explain the Normal Start sequence.

Answer 37

- ENG MODE to IGN/START - ENG MASTER to ON - Observe Start Valve Open and gray N2 background - At 16% N2 Ignition (A or B) on - At 22% N2 HP Fuel - At 50% N2 starter cutout - Approximately 58% grey N2 background disappears - Idle at 60%

Question 38

Explain the Manual Start sequence.

Answer 38

- ENG MODE to IGN/START - ENG MAN START pushbutton ON - At maximum N2 motoring speed (Min 20%), ENG MASTER ON - Observe AB ignition, fuel flow increase, EGT and N1 increase in 15 seconds - At 50% observe N1 starter cutout and Ignition off - ENG MAN START pushbutton OFF

Question 39

What does a fault light on the ENG panel indicate?

Answer 39

- Auto Start Abort | - Switch disagreement between HP valve and its commanded position

Question 40

With the ENG MODE selector in the IGN/START what occurs when you press the ENG MAN START pushbutton?

Answer 40

- The start valve opens | - Both pack flow control valves close

Question 41

What does an amber "FAULT" light in the ENG PUMP pushbutton indicate?

Answer 41

- Pump pressure low - Overtemp in the reservoir - Low air pressure in the reservoir - Low quantity in the reservoir

Question 42

Will the start valve then automatically close?

Answer 42

Yes, at 50% N2

Question 43

What causes the amber "FAULT" light on the ENG 1 BLEED and or ENG 2 BLEED pushbutton? (OOLD)

Answer 43

- Overpressure - Downstream of the bleed valve - Overheat - Leak - low pressure - Discontinuity - APU bleed valve open and engine bleed valve not closed or Engine Start with bleed valve not closed

Question 44

What are the two functions of the engine bleed valves?

Answer 44

- Pressure Regulation | - Shut off Valves