Sovereign APU

Question 1

From what wing is the APU supplied fuel?

Answer 1

Right

Note: Can receive fuel from the Left via X-FEED

Question 2

What is the approximate fuel burn?

Answer 2

65 pph, 120 pph using Bleed Air

Question 3

Max EGT

Answer 3

690 C

Question 4

What happens when selecting MAX COOL?

Answer 4

Bleed Control Valve fully opens after 20 seconds

Question 5

From what bus is the APU powered?

Answer 5

Left EMER BUS

Question 6

What happens to APU with loss of DC power?

Answer 6

APU shuts down

Question 7

Why should MAX COOL not be used in manual mode?

Answer 7

Could cause an over temp in the under floor ducting, if Temperature Control Valves (TCV) were selected full open

Question 8

Describe an APU test prior to start?

Answer 8

1. Must wait 60 seconds after the BATTERIES and APU MASTER are selected ON to receive a complete test. (won’t receive the aural portion of test)
2. All APU Panel lights will illuminate
   Note: APU BLEED and GEN Buttons will indicate last position and there is no light in the RESET button
3. Red APU FIRE will appear on CAS
4. Amber APU FIRE DETECT FAIL will appear on CAS
5. APU Fire aural warning is announced 3 times

Question 9

What does APU SYSTEM FAIL message on CAS indicate?

Answer 9

ECU detects a fault prior to start, or

ECU initiated shutdown due to a limit exceeded or loss of sensors

Question 10

How can you prevent the passengers for hearing the Aural Warnings?

Answer 10

Select MUTE

Question 11

When are Transient amps allowed?

Answer 11

Engine Start +2 minutes

Question 12

What must be checked during APU Start at 50% RPM?

Answer 12

GCU opens the APU RELAY (cyan APU RELAY ENGAGED light on APU Panel extinguishes)

Question 13

What does the cyan APU RELAY ENGAGED light on the APU Panel indicate?

Answer 13

That the APU RELAY is CLOSED either for APU Start or the APU Generator is connected to the Left EMER BUS

Question 14

What could prevent the APU from Starting?

Answer 14

1. Cyan FIRE BOTTLE BAGGAGE/APU LOW message

2. APU FIRE DETECTION FAIL message

Question 15

Why should you turn OFF APU BLEED AIR prior to Engine Start?

Answer 15

Prevents exhaust fumes from entering the Air Conditioning System

Question 16

What CAS messages will cause the APU to automatically shutdown?

Answer 16

1. Cyan FIRE BOTTLE BAGGAGE/ APU LOW
2. Red APU FIRE
3. Amber APU FIRE DETECT FAIL
4. Amber ACM BLEED LEAK

Question 17

When does the READY TO LOAD light illuminate?

Answer 17

95% +4 seconds

Question 18

What valve does the APU MASTER open and close?

Answer 18

APU Firewall Shutoff valve

Question 19

How long can you go with the APU oil amber light illuminated in the tail cone?

Answer 19

20 hours

Question 20

If you didn’t notice if the APU RELAY ENGAGED light went OFF at 50% during Start, what could you do?

Answer 20

Check volts and amps if less than 28 volts and zero turn OFF the APU Generator. The relay should OPEN extinguishing the light

Question 21

Why must you close the BUS TIE to Start the APU in flight?

Answer 21

To allow both batteries to participate

Question 22

Can you Start the APU after a dual generator failure?

Answer 22

One attempt is permitted