Fire Protection and APU Flashcards
True or False: During normal operations, both detection loops must detect a fire before a warning is generated
TRUE
______ Halon Bottle(s) are installed in the aft equipment bay for engine fire suppression for the main engines
2
If an APU fire occurs in flight, what will happen?
The APU shuts down automatically, but the fire extinguishing bottle must be manually discharged
If an APU fire is detected while on the ground, what will happen?
The APU will automatically be shut down and it’s bottle will be AUTOMATICALLY discharged.
Fire Extinguishing for the forward and aft cargo compartments is provided by:
Two halon fire extinguisher bottles
When a cargo fire is extinguished, what will happen?
Both bottles will simultaneously discharge into the selected compartment. The high rate quickly discharges, the low rate will slowly discharge over a 60 minute period
What are the flight deck indications that the lavatory waste bin extinguisher has been discharged?
There are no flight deck indications that the bottle has been discharged
What happens when I push the engine fire switch light?
- Bottle squibs are armed (green light)
- Closes the Bleed air SOV (ECS on EICAS status)
- Closes the Hydraulic SOV (HYD on EICAS status)
- Trips off the affected engine generator (ELEC)
- Closes the Fuel SOV (FUEL)
How can the APU be shut off?
- START/STOP
- AC External Panel
- Emergency Stop in Tail Compartment
What accessories are mounted on APU gearbox?
Fuel Control Unit (FCU)
Lubrication Module
Electric Starter/Generator
APU door position depends on:
- Weight on Wheels
- APU RPM
- Aircraft Speed
The APU OVERSPEED EICAS warning will appear if APU RPM is greater than ______
106%
Fuel from the APU operation is supplied from the:
Left Collector Tank
The ECU will shut down the APU for:
Overspeed and loss of overspeed protection
What is the APUs primary and secondary purpose?
Primary: provide AC Power
Secondary: Bleed air
APU Model
Honeywell RE220
What happens when PWR FUEL light is pressed?
- APU fuel pump energized
- APU Shut-off valve opens
- APU EICAS gages and APU IN BITE message are displayed.
- ON THE GROUND, air inlet door is scheduled to open
Describe APU starter.
DC Starter
AC Generator
What happens when the APU START/STOP switchlight is pressed?
ECU will…
- Energize starter motor
- Fuel and ignition on at 5%
- 46-60% rpm (altitude dependent)
- At 99% rpm + 2 seconds, the green AVAIL switchlight illuminates.
What will cause an APU fault message?
HOTLOP
What happens when the APU START/STOP switchlight is pressed while the APU is running?
- Green AVAIL switchlight extinguishes
- APU fuel shutoff solenoid closes
- APU RPM and EGT decrease
- APU intake door closes when rpm decreases below 25% rpm
- EICAS parameter DOOR CLSD displayed
Why can the APU indicate low oil pressure at higher altitudes?
APU is not pressurized, can cause foaming of oil at higher altitudes.