APU Flashcards
True or False: A dedicated FADEC controls the APU.
True
What power sources can be used to start the APU?
DC GPU or BATT 2 (5.14 Vol 2)
Fuel for the APU can be provided by the _______ tank through the crossfeed
Valve.
left
Which fuel tank usually provides the APU with fuel during normal operations?
Right
The _______ provides control of the APU bleed air operations
AMS controller
(Air Management System)
The APU can provide AC electrical power up to __________ ft.
33,000 ft
[start up to 30,000 ft, bleed air for engine start up to 21,000 ft, bleed for air up to 15,000 ft]
True or False: APU bleed control is located on the APU control panel.
False
True or False: The APU will auto shutdown while airborne for a high oil
temperature condition.
False
The APU cooldown period prior to shutdown is _____.
1 min.
True or False: The APU will auto shutdown on the ground for a low oil pressure condition.
True
After the spool-down period of the APU is over, the EICAS message APU
SHUTTING DOWN will _______.
dissapear / Be removed
True or False: Selecting the APU control knob to OFF shuts down the APU.
True
True or False: The APU can be shut down using the emergency shutdown button, but will take 1 minute to cool down.
False [without the 1 min cooldown]
True or False: The APU is controlled by the left engine’s FADEC.
False
If OFF is selected while the APU is running, the shutdown sequence _______.
Is initiated
can be canceled if the knob is reselected to ON within the 1-minute cooldown period
True or False: The APU must be shut down before every takeoff.
False (ON for ECS OFF takeoff 2.10.1 Vol 1)
When are electrical and pneumatic loading available during an APU start?
3 sec. After the APU has reached 95% RPM
True or False: During the normal shutdown sequence, APU bleed air is
immediately stopped and electrical power is removed after a 1-minute cooldown period, followed by a spool-down period.
True
In flight, the APU automatically shuts down for which of the following conditions?
Overspeed,
underspeed,
FADEC Critical Fault
True or False: If BATT 2 is below temperature limits, AC external power can be used to start the APU.
False (DC GPU 5.14 Vol 2)
During an APU fire, what will occur if the APU fire extinguisher button is pressed without first pressing the APU EMER STOP button?
Halon would be exhausted because the APU is still spinning!
closes the APU fuel shutoff valve (SOV) - shutting down the APU,
Discharges the APU fire bottle,
displays an “APU FIREX BTL DISCH” EICAS advisory message (7.5 Vol 2)
