Systems Questions Flashcards
What is the definition of Total Air Temperature
The temperature of the air corrected for compressibility and friction caused by high speed
On the ground with probe heat ON which probes are heated?
All pitot tubes are heated half way, all others are heated fully except for the TAT probe which is not heated on the ground
In flight which probes are heated?
All probes are heated in flight regardless of probe heat switch position
Max altitude for APU start?
37,000 feet
Max altitude for APU operation?
41,000 feet
Max permissible load on APU generator?
40 Kva
Max altitude for APU bleed air extraction?
25,000 feet
Max speed for APU door open or unknown?
220 Knots if APU is not operating and no speed limit if it is operating
What battery voltage is required before starting APU?
22 Volts
What does the main battery power during APU start?
APU ECU
What does the APU battery power during APU start?
Cranking of the 28 volt DC Motor
When will the AVAIL switchlight illuminate?
99% plus 2 seconds
What is the thrust rating without APR?
13,560 lbs
What is the thrust rating with APR?
14,750 lbs
What is the max ambient temperature for takeoff and landing?
ISA + 35 degrees C
What is the min ambient temperature for takeoff and landing?
-40 degrees C
What is the max altitude for windmill start?
21,000 feet msl
Max engine to engine N2 split at ground idle power?
2%
How much thrust is produced by core air
20%
How much thrust is produced by bypass air?
80%
How many stages of compression do we have?
The engine is equipped with a 10 stage axial flow compressor
What accessories are driven off the N2 accessory gear box? (Fish oil plus)
Fuel pump (engine driven) IDG Starter (air turbine starter) Hydraulic Pump (engine driven) Oil pump Fadec Alternator (+)
What is the engine bleed air used for?
Engine start
Air conditioning
Pressurization
Wing and Cowl Anti-ice
What stages of bleed air are used?
Normally 6th, and 10th stage is used when demand exceeds capability of 6th stage
What allows 10th stage bleed air availability?
Air conditioning system controller (ACSC) automatically opens the high pressure valve (HPV)
How many igniters are installed on each engine?
2, igniter A and igniter B
What are the Parameters required before fuel can be introduced on a ground engine start?
20% or greater N2
ITT less than 120 degrees C
What is the air pressure requirement provided by the operating engine to initiate a cross bleed start?
42 PSI to a maximum of 80% N2
When will APR arm on takeoff?
Engine speed within 8% of scheduled takeoff power (normal or flex)
When will the APR system activate?
Thrust levers in TOGA
Normal or flex thrust scheduled
And N1’s differ by 15% or more or when thrust levers are set in the MAX Power detent
What occurs when the APR system activates?
FADEC commands an N1 increase dependent on thrust lever position
What indication will we have of APR activation?
Green APR icon on operable engine gauge
If an engine fails on a go-around will the APR system activate?
Yes
What is used to deploy and stow the thrust reversers?
Hydraulics
L thrust reverser uses hydraulic system 1
R thrust reverser uses hydraulic system 2
In MAG mode how long does it take the AHRS system to initialize ?
30-70 seconds
In DG mode how long does it take the AHRS system to initialize?
10-11 minutes
What happens when TOGA is pushed on the ground?
TO Lateral mode
TO vertical mode
FMS aligns the aircraft at the end of the runway indicated on legs page
Autopilot disconnects
What is occurring during thrust reverser deployment?
The translating cowls move aft and bypass air is redirected through cascade vanes which redirect air forward
What happens when thrust reverser inadvertently deploys?
FADEC commands reverser to close and thrust set to idle on affected engine
Min oil temp for engine starting?
-40 degrees C
Max continuous oil temp
155 degrees C
Engine starter cranking limits (ground)
Attempts 1-2 are 90 seconds on and 10 seconds off
Attempts 3-5 are 90 seconds on and 5 minutes off
How is the oil cooled?
Fuel/oil heat exchanger
What is the max fuel imbalance
300 lbs for takeoff and 600 lbs for all other phases
Max differential pressure is
8.7 psi
Normal differential pressure is
8.5 psi
What are the APU starter limits?
No more than 3 start attempts in one hour, 2 minute delay required between start attempts
What are the dry motor limits?
Attempt 1 - 90 seconds on and 5 min off
Attempt 2 thru 5 - 30 seconds on and 5 min off
Max permissible oil temp?
165 degrees C (15 min max)
What are the fuel quantities for pressure refueling?
Total - 19,594 lbs
Mains - 7,492 lbs
Center - 4,610 lbs
What are the fuel quantities for gravity refueling?
Total - 14,810 lbs
Mains - 7,405 lbs
Center - N/A
How is the fuel moved from the center tank to the main tank?
Transfer ejectors
How is the fuel moved from the main tanks to collector tanks?
Scavenge ejectors and gravity fuel feed as backup
How is the fuel moved from the collector tanks to the engine driven high pressure fuel pump?
Main ejectors (backed up by boost pumps)
What is the function of the electric boost pumps?
To provide initial fuel for engine start and to back up the main ejectors
What is the flight deck indication of high pressure fuel pump failure?
Engine flameout
When will the fuel system automatically begin transferring fuel?
200 lb imbalance
When are the boost pumps automatically energized?
Low pressure from the main ejectors (if the pumps are armed)
Where is bulk fuel temperature taken?
Right main tank
What is the minimum bulk fuel temp for takeoff?
-30 degrees C
What is the minimum bulk fuel temp for flight
-40 degrees C
How is engine fuel heated?
Fuel/oil heat exchanger
What is the minimum engine fuel temperature for takeoff?
5 degrees C
What is the takeoff limitation if the center tank has more than 500 lbs?
Then each main tank must have over 4,400 lbs
Which bus powers the refuel/defuel panel and refuel/defuel SOVs?
APU battery direct bus
Max pressure differential during taxi, landing, takeoff?
0.1 psi
Max negative pressure differential?
-0.5 psi
Max altitude for single pack operations?
FL 250
What does the DISPLAY COOL or ARINC COOL caution messages mean?
Low airflow behind the screens or within the avionics rack
How many pressurization controllers are installed on the CRJ 900?
2
PC 1 and PC 2
When do pressurization controllers swap?
Weight on wheels plus 3 minutes or,
If one PC fails the redundant controller takes over
When operating in auto mode, what is the cabin rate of climb and descent?
500 ft climb
300 ft descent
When operating in manual mode, what range is controlled by the MAN RATE knob?
50 fpm to 3,000 fpm
+/- 1,000 fpm
When will we get a CABIN ALT caution message?
Cabin altitude between 8,500 to 10,000 feet
When will we get a CABIN ALT warning message?
Cabin altitude over 10,000 feet
When will CPAM automatically deploy the passenger oxygen masks?
Cabin altitude above 14,000 feet
How many smoke detectors in aft cargo bay?
2
