Power Plant/ APU

Question 1

Explain the meaning of the FLAP OPEN and LOW OIL LEVEL indications on the ECAM APU page

Answer 1

FLAP OPEN
-APU air intake flap is fully open
-Flap is commanded open when APU MASTER SW pb is selected ON
-APU starter motor is inhibited until flap is fully open

LOW OIL LEVEL
-APUs oil tank quantity is sensed to be low
-indication would appear immediately when the APU MASTER SW pb is selected to ON and the aircraft is on the ground

NOTE with LOW OIL LEVEL indicated, the APU START should not be selected ON. Contact maintenance.

Question 2

Recall the indications when the APU is “on speed”

Answer 2

AVAIL appears on the
-APU START pb
-ECAM APU page

APU AVAIL appears on ECAM memo section

Question 3

Recall the function of the APU MASTER SW pb

Answer 3

ON
-APU computer is enabled and preforms a self test
-Air intake flap is commanded open

Light out- APU computer is deactivated, and the APU shuts down

FAULT- an automatic shutdown or failed start has occurred

NOTE selecting the APU MAST SW to OFF (light out) will accomplish a normal shutdown sequence

Question 4

Explain why the aircraft batteries must be on for all APU starts and when the APU gen is the sole source

Answer 4

1. Turning the batteries ON permits the APU starter motor to connect to the aircraft battery buses, which are the only power sources available to the starter motor
2. On the ground, in the even of an APU fire while the APU gen is the sole source of power, the batteries being on ensure a power source for proper APU shut down and extinguisher discharge

Question 5

Recall the function of the APU BLEED pb and APU GEN pb

Answer 5

APU BLEED pb
-ON commands the APU bleed valve open
APU GEN pb
-lights out- APU gen will automatically energize once the APU is on speed
-OFF- APU gen is de-energized

Question 6

Recall the uses of APU bleed air

Answer 6

APU bleed air CAN be used for
-Engine starts
-Air conditioning and pack operation
APU bleed air CANNOT be used for
-Wing anti-icing

Question 7

Which start malfunction a FADEC cannot sense a therefore cannot automatically abort

Answer 7

Tailpipe fire

NOTE this start malfunction requires the pilot to manually abort the start by placing the respective ENG MASTER switch to OFF

Question 8

Recall how continuous ignition can be manually activated

Answer 8

Following an engine start, cycle the ENG MODE selector from NORM back to IGN/START

NOTE IGNITION appears in the memo section of the E/WD whenever continuous ignition is active. This is the only indication that the system is active

Question 9

Recall the engine igniter displays on the ECAM ENGINE page

Answer 9

-Engine igniters are displayed as A and B
-During engine start, A or B, appears at the lower portion of the ECAM ENGINE page indicating active igniter
-AB indicates that both igniters are being used for that engines start or continuous ignition is active

NOTE FADECs independently alternate which igniter is used with each engines start.

Question 10

Recall the E/WD N1 gauge indications

Answer 10

Green- digital numeric N1 speed and analog green line N1 speed
Amber tick mark- FADEC computed max N1 for current ambient conditions
Red arc- Max permissible
Circle- current position of the associated thrust lever
Blue arc- indicates the difference between actual N1 and the thrust commanded by the auto thrust system
Boxed amber REV- one or more of the thrust reverser blocker doors is not stowed or not locked
Boxed green REV- all four reverser blocker doors are deployed

Question 11

Recall the meaning of the grey background of an N2 display on E/WD

Answer 11

An engine sequence is in process. When the start sequence is complete or aborted, the grey background is removed

Question 12

What are the functions of the controls and indications on the ENG panel
ENG MASTER 1(2) switches

Answer 12

ON- initiates the automatic start sequence when ENG MODE selector is set to IGN/START
OFF- Shuts down the engine or aborts the start sequence

Question 13

What are the functions of the controls and indications on the ENG panel
ENG MODE selector

Answer 13

NORM- normal operation following an engine start
IGN/START- Selected prior to all engine starts
-displays the ECAM ENGINE page on the SD
-Activates both FADECs
-Commands both pack valves to close for 30 seconds
-Increases APU speed (If being used)
-Following an engine start, continuous ignition is activated when cycled from the NORM position
CRANK selected to Dry crank/ventilate the engine
-No fuel or ignition will be supplied
-Displays the ECAM ENGINE page on the SD
-Activates both FADECs
FIRE- illuminates when an engine fire is detected
FAULT illuminates when
-Automatic start has been aborted (FADEC start fault)_
-There is a disagreement between the actual position of the HP fuel valve and its commanded position

NOTE there is no relationship between the FIRE and FAULT indications. They are separate indications

Question 14

Explain what occurs when an ENG MAN START pb is selected ON

Answer 14

The respective engine start valve opens provided:
-ENG MODE selector is in IGN/START or CRANK
-Bleed air pressure is available
The respective start valve automatically closes at approx. 50% N2 but the ON remains illuminated until reselected

Question 15

Describe the igniter behavior during automatic verses manual starts

Answer 15

Automatic starts- engine igniters alternate between starts (A or B). FADEC automatically controls the ignition
Manual Starts- Both igniters are activated (AB) only after the engine master switch has been selected on

Question 16

Describe the position of the EGT limit tick mark (amber) on the EGT display during and after engine start

Answer 16

-During engine start, the tick mark moves to the start EGT limit
-When the start is complete the tick mark returns to Max Continuous Thrust (MCT) EGT limit