Flashcards in APU Panel Deck (10):
What does the APU MASTER SW pb to ON do?
• Electrically powers the APU system (Blue ON light in pb)
• ECB performs a power up test
• APU ECAM page appears (if EXT or ENG GEN AC power is available)
• APU air intake flap opens
• APU fuel isolation valve opens
• APU fuel pump operates (if no tank pumps are on)
What happens when you push the APU START pb?
• Blue ON light illuminates
• When APU air intake flap opens the starter is energized
• Ignition is turned ON 1.5 seconds after starter is energized
• Starter is de-energized and ignition turned OFF at 55% N
• Blue ON light in START pb extinguishes
• Green AVAIL light illuminates 2 seconds after 95% N or above 99.5% N
• APU page disappears from the ECAM 10 seconds later
With the APU running and supplying bleed air, how do you shut it down?
• APU BLEED pb OFF
• APU MASTER SW OFF
• APU will cool down and then shut down
What does the green AVAIL light on the APU START pb indicate?
The APU is available to provide electrical power and/or bleed air
With the APU green AVAIL light ON and the EXT PWR green AVAIL light on, which system is powering the
If the APU is running, is it necessary to manually select APU BLEED OFF prior to APU shutdown?
No. When the APU MASTER SW is selected OFF, the bleed air valve is closed and the APU is allowed to cool prior to shutdown
During the cool down cycle can you still use the APU?
Yes, press the APU MASTER SW pb
An amber FAULT light in the APU MASTER SW pb indicates?
An APU auto shutdown has occurred
What does an amber FAULT light in the APU BLEED pb mean?
An APU bleed leak