APU

Question 1

The APU fuel pump receives its power from:
(A). AC BUS

(B). DC BUS 1

(C). DC EMER BUS

(D). BATTERY BUS

Answer 1

BATTERY BUS

Question 2

The maximum ECS bleed altitude for the APU is:
37,000
41,000
25,000
21,000

Answer 2

25,000’

Question 3

The fuel source for the APU is:

(A). From the left collector tank

(B). From the right main tank

(C). From the right engine feed manifold

(D). From the fuel transfer manifold

Answer 3

From the left collector tank

Question 4

The green AVAIL light in the APU start/stop switchlight means:
(A). APU bleed air is available

(B). APU is able to supply electrical loading

(C). APU is running

(D). APU BITE test is complete

Answer 4

APU is able to supply electrical loading

Question 5

The maximum operating altitude for the APU is:
37,000
41,000
25,000
21,000

Answer 5

41,000’

Question 6

The minimum battery voltage to start the APU is:
22
24
28

Answer 6

22 volts

Question 7

The APU generator can only supply half as much power as an engine driven generator.
t
f

Answer 7

False

Question 8

If the APU door actuator fails, the aircraft cannot be dispatched until the condition is corrected.
t
f

Answer 8

False

Question 9

If the APU door position is unknown, airspeed is restricted to _____________ or _________________.
A.) 250 KIAS/remain off

B). 230 KIAS/remain in operation

C). 250 KIAS/remain in operation

D). 220 KIAS/remain in operation

Answer 9

220 KIAS/remain in operation

Question 10

Inflight, the APU door opens upon:
A). Selection of the PWR/FUEL switchlight

B). Selection of the START/STOP switchlight

C). Reaching 50% during the start cycle

D). Reaching 99% during the start cycle

Answer 10

Selection of the START/STOP switchlight

Question 11

APU EGT is indicated on the EICAS ________ page.
STATUS
Primary
MENU
ECS

Answer 11

STATUS

Question 12

When the APU is supplying bleed air, you can expect a decrease in in APU EGT.
t
f

Answer 12

False

Question 13

During the APU start, the fuel shutoff solenoid is activated open at ________.
5%
8%
12%
17%

Answer 13

5% rpm

Question 14

During APU start the ECU gets its power from the ____________ and the Starter from the ____________.
A). BATT BUS/DC ESS BUS

B). MAIN BATT DIR BUS/APU BATT DIR BUS

C). APU BATT DIR BUS/BATT BUS

D). BATT BUS/APU BATT DIR BUS

Answer 14

BATT BUS/APU BATT DIR BUS

Question 15

Inflight, a relight attempt of the APU can be initiated once the APU rpm rolls down below________.
8%
12%
15%
18%

Answer 15

12%

Question 16

The APU duty cycle is limited to no more than ______ starts or start attempts in 1 hour.
3
4
5
6

Answer 16

3