APU

Question 1

How many seconds must you wait between attempted APU starts?

Answer 1

15.

Question 2

During a Wing/APU fire on the ground, you have a verified fire with the firegaurd, your next step would be to?

Answer 2

Execute Emergency Shutdown.

Question 3

If the APU system SBIT indicates a FAULT what will you see on the MFD WRA TEST Status Page?

Answer 3

F(S) in the stat column next to the failed component.

Question 4

Electrical operating power for the APU engine system consists of __________.

Answer 4

28 Volts Direct Current (VDC)

Question 5

What are the five EMERGENCY SHUTDOWN steps?

Answer 5

Verify, APU, Battery, Egress, Ground Control.

Question 6

The components driven by the MWGB during APU operation are?

Answer 6

No. 3 Hydraulic Pump/Oil Cooler Blower/Shaft Driven Compressor

Question 7

__________ shall not be selected for normal operations. Damage to aircraft may occur.

Answer 7

Emergency Run/Engage

Question 8

APU is limited to ground operations.

Answer 8

TRUE.

Question 9

During APU crank mode a time-out feature limits this operation to __________ seconds maximum.

Answer 9

30

Question 10

The APU can only be started with external power on.

Answer 10

FALSE.

Question 11

The APU system interfaces with the drives the MWGB to provide electrical, hydraulic, and pneumatic power for…

Answer 11

TRUE.

Question 12

Automatic shutdown protection is not provided for which of the following?

Answer 12

Low fuel pressure.

Question 13

Prior to APU start, the WFPS shall be DISABLED if any panels are removed from the wing/midwing.

Answer 13

TRUE.

Question 14

Fuel is supplied to the APU by the __________.

Answer 14

RH Feed Tank

Question 15

If the APU fails to start after 3 attempts, APU Start motor shall be allowed to cool for __________ minutes before attempted.

Answer 15

55

Question 16

The APU control panel is labled Run/Engage, Run/Disengage, Emergency Run/Engage, Crank, and

Answer 16

STOP.

Question 17

A maintenance/VSLED download is required after every APU run.

Answer 17

FALSE.

Question 18

The #3 Hydraulic system pressure should read between __________.

Answer 18

4600-5250

Question 19

If the WFPS is DISABLED no wing fire detection/protection is available.

Answer 19

TRUE.

Question 20

When the APU is started, which generator(s) is on line?

Answer 20

CFG #1.

Question 21

WFPS control switch is located on wihich PDP?

Answer 21

PDP 3.

Question 22

The first step of the APU checklist is __________.

Answer 22

Aircraft safe for maintenance.

Question 23

During Run/Disengage mode the APU will perform the same function as the Run/Engage except the __________.

Answer 23

Clutch

Question 24

At what temperature must the APU clutch be preheated for 15-30 minutes?

Answer 24

-25 Degrees F and below.

Question 25

Which of the following is NOT checked for servicing at the GRDP?

Answer 25

CFG.

Question 26

When operating the APU in the CRANK mode, how long will the APU motor?

Answer 26

30 seconds.

Question 27

The APU engage ASI will show up on the __________.

Answer 27

CDU

Question 28

What is the minimum battery voltage required for APU start?

Answer 28

23.5 Volts.

Question 29

The first step in the Wing/APU fire on the ground checklist is

Answer 29

Verify APU fire with firegaurd.

Question 30

To prevent inadvertent actuation, the NAC CONT DSBL switches shall be selected to DSBL anytime nacelles are…

Answer 30

TRUE.

Question 31

The APU ignition is initiated with two ignitors which receive __________ volts from the ignition exciter.

Answer 31

5000

Question 32

Once the APU has started, the fuel system will maintain what constant turbine speed?

Answer 32

98-102%.

Question 33

The APU start motor will disengage at __________ percent of the APU self-sustaining speed of 100%.

Answer 33

50

Question 34

In the event of a Wing/APU fire on the ground, the last step is to?

Answer 34

Alert Ground Control.