Systems Questions (Oral and Test) Flashcards
Is there a speed limit for ADG deployment?
Yes, Vmo (335 Kts)/Mmo (0.85 Mach)
What is on the accessory gearbox?
- fuel pump (engine driven high pressure)
- integrated drive generators
- starter (air turbine)
- hydraulic pumps (engine driven) - EDP’s
- Oil Pump
- FADEC Alternator (+)
When does APR automatically arm?
When N1 RPM of both engines are within 8% of takeoff power, (normal or reduced)
What type of takeoff thrust setting is automatically calculated by FADEC?
Normal Takeoff thrust
What conditions are you looking for to move the thrust lever to idle position after engine start?
- N2 greater than 20%
AND
- ITT is 120 degrees or less
What doors are NOT on the Synoptics page?
- AFT equipment bay
- Crew Escape Hatch
How much core air thrust is produced by the CF34-8C5 (CRJ 900) engine?
20%
How much bypass air thrust is produced by the CF34-8C5 (CRJ 900) engine?
80%
How much engine thrust is produced by APR?
14,750 lbs
When will FADEC automatically increase thrust to the operating engine?
When an engine fails and N1 mismatch of 15% or more is detected
When is continuous ignition required?
- Takeoffs/Landings on contaminated runways
- Flight through moderate or heavy rain
- Flight through moderate or greater turbulence
- Flight in vicinity of thunderstorms
When does the air turbine starter disengage on the starter system?
N2 reaches 50%, of the STOP Switch light is pressed
When do we want to introduce fuel on an engine start (moving the thrust lever to idle position)?
- N2 is 20% or greater AND ITT is less than 120 degrees C
If NOT followed (HOT START will occur and FADEC will not allow engine to start)
FADEC will automatically abort a start for…
- Hung Start
- Hot Start
- L(R) START ABORT (caution message will be displayed)
Where is the Oil Replenishment Tank located?
AFT Equipment Bay
Reference Slide #73 - Powerplant
What stage of compression is bleed air extracted from?
6th and 10th stage
What are the thrust lever Detents located?
- Climb
- TOGA
- Max Power
What hydraulic system powers the left thrust reverser? Right thrust reverser?
- Left thrust reverser powered by hydraulic system # 1
- Right thrust reverser powered by hydraulic system # 2
Where is the APU located?
Located in the aircraft tail one
What causes the APU to automatically shutdown on the ground?
High Oil Temperature, Loss of Oil Pressure (“HOTLOP”)
In flight, what happens when there is a loss of oil pressure or high oil temperature in the APU?
Caution Message will appear on EICAS display but APU will continue to operate
Where does the APU receive fuel from?
Left collector tank via the APU fuel pump
What voltage on the batteries are we looking for prior to starting the APU?
Minimum of 22 volts on main battery and APU battery
Why do we need a minimum voltage on the main battery and APU battery prior to starting the APU?
Main battery powers the ECU, APU battery provides power to crank the starter
When we press PWR/FUEL switch light, what are we looking for on the EICAS display?
Look for “DIGS”
- DOOR OPEN
- IN BITE status message
- GAUGES (RPM and EGT) are displayed
- SOV OPEN status message
When can we press the START/STOP Switch light on the APU?
APU IN BITE status message disappears
When we press the START/STOP switch light on the APU what are we checking for?
- START switch light illuminates
- APU START status message is displayed
- APU Starts
When does the APU START switch light extinguish?
When starter cutouts, occurs between 46-60% RPM
When does the APU START status message disappear?
When starter cutouts, occurs between 46-60% RPM
When does the APU AVAIL light illuminate?
99% plus 2 seconds
What does the APU AVAIL light mean?
The APU is available for electrical loading
What is the Primary Purpose of the APU?
Electrical, to operate the gearbox mounted (40 KVA) generator
What is the Secondary purpose of the APU?
- Supply Bleed Air for Air Conditioning
- Supply Bleed Air for Pressurization
- Main Engine Starting
How long do you have to wait after the APU AVAIL light comes on for using the APU for bleed air?
Pneumatic loading will be available 99% plus 2 seconds
When does the APU automatically shut down?
On the ground after 5 seconds
What PSI does the APU LCV (load control valve) modulates to?
Regulates manifold pressure of 45 PSI
What is the purpose of the APU LCV (Load Control Valve)?
Protects the APU from over temperature condition
Why is gravity refueling fuel limits less than the pressure refueling limits?
Because of dihedral of the wing
Why is the NACA scoop designed in that shape?
To prevent ice buildup
How many motive flow ejector pumps are there? What are their names?
8 Ejectors
- 2 Transfer Ejectors
- 4 Scavenge Ejectors
- 2 Main Ejectors
Explain the use of the Transfer Ejectors…
Transfer ejectors are controlled by motive flow created by main ejectors
Transfer ejectors sends fuel from the center tank (when in use) to the Main Tank.
They automatically are activated when the main tank drops to 94% of fuel capacity (on the respective side).
The FSC (Fuel System Computer) will open the respective transfer valve, then close the respective transfer valve when the tank is full
This process continues until the center tank is empty
Explain the use of the scavenge ejectors…
Scavenge ejectors takes fuel from the main tanks to the collector tanks
2 per main tank (Synoptics page only shows one)
Gravity line connects the main tanks to the collector tanks to act as redundancy in case the scavenge ejectors fail
Explain the use of main ejectors…
Two main ejectors are operated by motive flow created by the the engine driven fuel pumps
Main ejectors takes fuel from the collector tank and delivers fuel to the engine
Reference Systems Manual Pg. 410, Ch. 11-8
Explain what will happen if the Engine driven fuel pump (EDP) stops working…
Nothing, the associated engine will quit
What is the purpose of the Fuel Boost pumps?
Acts as a back up to the main ejectors, when low pressure is detected
Moves fuel from the collector tanks to engines during engine start
How are the fuel boost pumps powered?
Electricity (electric boost pumps) DC powered
How will the Boost Pumps turn on?
- They need to be “ARMED” (pushed in)
- They need to sense a lower pressure from the main ejector on that side (by the Fuel System Computer)
- When one boost pump turns ON they BOTH TURN ON!
(If the left and right boost pump are pushed in “ARMED” and the left engine is running, but the right engine is NOT running, the right boost pump is sensing a LOW PRESSURE on that side, meaning it will TURN ON, this will make the LEFT fuel boost pump turn on as well… Being able to send fuel under low pressure to start the #2 (right) engine)
When will the INOP light on the Fuel Boost Pump turn on?
- Any time the fuel pump switch is not “ARMED” (pushed in)
- When the fuel boost pump has failed
What temperature the Fuel/Heat exchanger heats the fuel to?
5 degrees C
What does the ENGINE FIRE PUSH or APU FIRE PUSH switch light on glareshield do to the fuel system?
Stops the flow of fuel to the Engine (ENG FIRE PUSH) or stops the flow of fuel to the APU (APU FIRE PUSH)
- Electrically operated Fuel Shutoff Valves (SOV) will close with the push of the respective switch lights on the glareshield
When does the XFLOW pump automatically activates?
Imbalance of 200 lbs is detected
When does the XFLOW pump in AUTO mode automatically shutoff?
When the computer senses tanks are balanced plus 50 lbs on the low side
Regarding the fuel system, when will you use manual cross flow?
When auto Crossflow fails
Regarding fuel system, when will you use gravity cross flow?
When the XFLOW pump has failed
- Selecting the switchlight will allow the SOV to open, and gravity to balance the tanks.
- Put the plane into a side slip or “turn” to help the movement of fuel
What does EICAS mean?
Engine Indication and Crew Alerting System (EICAS)
Master warning, what will you see and hear?
Red message (Required IMMEDIATE corrective action)
Triple Chime will be heard
Cannot be boxed
Possibly an associated MASTER WARNING FLASHER (on glareshield)
Master caution, what will you see and hear?
Single chime
Amber messages (Requires PROMPT corrective action)
Messages can be boxed
Possibly an associated MASTER CAUTION FLASHER on glareshield
What are advisory messages?
Green messages
Shows safe conditions
Cannot be boxed
What are status messages?
White Messages
Shows certain conditions exist
Can be boxed
What conditions will allow you to get Takeoff Configuration Warnings?
“PASSFAR”
- Parking Brake
- Autopilot
- Spoilers
- Flaps
- Stab Trim
- Aileron Trim
- Rudder Trim
When will the Flight Data Recorder start record?
When BEACON or STROBE light switch is selected to on
What screen will show advisory message?
ED 2
What happens when ED1 fails?
Primary page is transferred to ED 2
What will happen if ED 2 fails?
It fails, there is no automatic transformation
What can you do if your PFD fails?
Use the Display Reversionary Panel (DRP) select PFD
What can you do if ED 1 fails? What about ED 2?
Use the Source Selection Panel (SSP) and switch to ED 2 (if ED 1 fails) if ED 2 fails, select ED 1.
How many AC generators do we have? Name the AC generators..
3 AC generators
- 2 Integrated Drive Generators (IDG)
- 1 APU generator (used for backup with engines running, or used on ground with engines off)
How many volts does the IDGs supply to how many AC buses?
115 volts, supplies power to 4 AC buses
What does the IDG consist of? (Two Components)
Constant Speed Drive
Generator
What is the generator rated at? And to what altitude?
40 KVA, 41,000 feet
The IDGs convert variable engine speed to constant generator speed of:
12,000 RPM
When does the FAULT light on the IDG Switch light located on the overhead panel illuminate?
“HOTLOP”
High Oil Temperature, Low Oil Pressure
How can the IDG be disconnected? What will happen?
Automatically or Manually (by pressing the IDG DISC switch light)
- Once it is disconnected it only can be reset on the ground by maintenance.
- If the electrical disconnect failed, it will disconnect mechanically by shearing of the IDG drive shaft when an over torque condition is detected
What is the purpose of the Generator Control Unit (GCU)?
Provides bus priority and protection during normal and non-normal operations
What is the output and rating of the APU? To what altitude?
Output is 115 Volts AC,
Rated at 40 KVA
To altitude of 41,000 feet
What conditions must be met for the green AVAIL light to illuminate on the AC Switch light?
Conditions of proper:
- Phase
- Voltage
- Frequency
Have been met
What is the exhaust danger area in feet?
100 feet
What is the radar hazard area?
2 feet
What is the limitation regarding passenger the passenger door?
1,000 lbs or 4 passengers
Name the AC buses on the CRJ 900
AC BUS 1
AC BUS 2
AC ESS
AC SERV
What is the bus priority for AC BUS 1?
- GEN 1, APU, GEN 2, EXTERNAL
What is the bus priority for AC BUS 2?
“ONSIDE, INSIDE, OFFSIDE, OUTSIDE”
- GEN 2, APU, GEN 1, EXTERNAL
What bus powers the AC ESS bus?
AC Bus 1
If AC BUS 1 fails, what bus is automatically transferred? To what bus?
AC ESS BUS, which is automatically transferred to AC BUS 2
What bus powers the AC SERV bus?
AC BUS 2
When the ADG is deployed, what does it power?
-
What can you do to prevent an “ADG STALL”?
Configure aircraft no later than 140 knots
What airspeed will the DC Essential bus load shed with the ADG deployed?
Between 155-160 Knots
Explain the use of the Power Transfer Override switch…
Used when one or more normal power generation systems has been recovered, with the ADG deployed.
- Important to re-establish normal AC power to avoid load shed of the DC ESS bus
Power for 28 VDC is supplied by:
- 4 Transformer Rectifier Units (TRUs)
How many Transformer Rectifier Units (TRUs) do we have on the CRJ 900?
4
What are the Transformer Rectifier Units (TRUs) rated at?
120 amps
What is the purpose of the Transformer Rectifier Unit (TRUs)
Transforms then rectifies 115 volt AC power to 28 volt DC power
How many and what buses do the TRUs supply power to?
4,
- BUS 1
- BUS 2
- ESS BUS
- UTIL BUS
What is the main battery rated at?
24 Volts DC, 17 Ampere-hour
What is the APU battery rated at?
24 volts DC, 43 Ampere-hour
What buses does the batteries supply DC power to?
- Main batt dir bus
- APU batt dir bus
- DC EMER bus
- DC batt bus
The main and APU batteries are kept in a charged condition by battery charger?
AC BUS 1 and AC Service bus
Fault protection for each generator is incorporated in each…
Generator Control Unit (GCU)
IDG 2 normally powers…
AC BUS 2
AC SERV BUS
What is the main battery rated at?
24 Volts DC, 17 Ampere-hour
What is the APU battery rated at?
24 volts DC, 43 Ampere-hour
What buses does the batteries supply DC power to?
- Main batt dir bus
- APU batt dir bus
- DC EMER bus
- DC batt bus
When on the ground with the ADG deployed we could lose power unless what…
ADG handle is pulled, otherwise battery power is removed from the DC ESS bus
When on the ground with the ADG deployed we could lose power unless what…
ADG handle is pulled, otherwise battery power is removed from the DC ESS bus
Which pack controls the flight deck?
Left pack
Which pack controls the cabin?
Right pack
How many smoke detectors are there in the fwd cargo bay?
Three
How many smoke detectors in the aft cargo bay?
Two
What does CPAM do with regards to oxygen masks?
Automatically drops oxygen masks at 14,000 feet cabin altitude
When does the CABIN ALT caution message come on
Greater than or equal to 8,500 cabin altitude
When does the CABIN ALT warning message occur?
Cabin altitude greater than or equal to 10,000 feet
Which Hydraulic pumps are running prior to pushback?
pump 3A
Which hydraulic pumps are running with one engine running (Taxiing)?
Pumps 1A, 3A
Which hydraulic pumps are running while you are taxing and second engine is running?
Pumps 1A, 2A, 3A
When reading the taxi checklist, which hydraulic pumps are running?
Pumps 1A, 1B, 2A, 2B, 3A, 3B
We are on takeoff and we lose the right engine, which pumps are running?
All pumps are running besides 2A
Once we clean up the airplane at acceleration altitude, what hydraulic pumps are running
1A, 3A, and then QRH will direct us to turn on 3B
If the APU fuel pump fails, will it shut down?
No, Internal bypass valve will open and high pressure gear driven pump will still be able to draw fuel in for the APU to operate
For an unattended APU fire on the ground, what will happen? In flight?
On ground, the APU will shut down automatically (sensing a fire by the dual loop protection) and 5 seconds later, the Firex bottle will be automatically discharged with Halon.
In Flight, the APU will shut down automatically, but the crew must discharge the Fire bottle manually
