APU Flashcards
When does the APU shut down immediately?
When an APU fault light illuminates
What does the APU run light indicate?
The APU may be used to supply electrical power and bleed air
What can cause the APU fault light to illuminate?
APU fuel valve not in commanded position
What is the maximum operating altitude for the APU?
Aircraft maximum certified altitude
What occurs when the APU selector is momentarily positioned to start?
Initiates automatic start sequence
What does the APU fault light indicate
APU automatic fault shut down
What are the electrical requirements for starting the APU?
Both the APU battery and the aircraft main battery
How can the APU shutdown be discontinued if the APU selector was inadvertently moved to off, but the run is still illuminated?
Momentarily moving the selector to start cancels the shut down signal
What causes the EICAS advisory message APU fuel valve to appear?
APU fuel valve fails to reach the commanded position
How many APU start attempts are allowed in a 60 minute period?
3
What affect does the battery switch selected to off have on the APU if running?
In-flight, none. On the ground, causes the APU to shut down with a cool down if required
Which of the following describes the start position of the APU selector?
Momentary, spring loaded to ON
