CRJ Systems Flashcards
Name the different sources of AC electrical power
- 2 Engine driven generators
- APU generator
- ADG
- External AC power
What is required for the green AVAIL lamp to illuminate in the AC external power switch light on the electrical panel?
Proper voltage, frequency, and phase
After turning on the battery master switch and prior to establishing AC power, is it normal to see the AC ESS XFER switch light to be illuminated? What does it mean?
Yes; AC Bus 1 is not powered so the AC ESS bus is trying to transfer to an operating BUS.
Describe the component of the IDG.
The IDG has two sub components.
- Constant speed drive
- Electrical Generator
Under what conditions will the IDG Fault caution message be displayed?
HOTLOP: High Oil Temperature; Low Oil Pressure
Is the IDG still producing power when the IDG fault message is displayed?
Yes; it will continue to generate power until it is disconnected.
Will the IDG DISC switch light be illuminated with the engine shutdown at the gate if the IDG is disconnected?
Yes
As directed by QRH, IDG 1 is disconnected. Can this be reversed in flight?
No, it can only be reset on the ground.
Describe AC power priority for AC Bus 2.
- Gen 2
- APU Gen
- Gen 1
- External Power
What does the AUTO XFER caution message mean?
-AC power priority did not automatically transfer due to a short in an electrical bus.
This prevents one short from destroying the entire electrical system.
Is there a difference between the meaning of AUTO XFER caution message and the AUTO XFER OFF status message?
Yes.
Caution message means the transfer is inhibited automatically.
Status means it was inhibited manually by the crew.
What would cause the AC Utility buses to load shed while on the ground?
- Operating on one generator.
- Flaps not 0
- MCD and Service door are closed.
What would cause the AC utility bus to shed in flight?
-Single Generator Operations
Under what conditions would the ADG automatically deploy?
- Loss of all AC power.
- Last source was internal.
- Weight off wheels
- Parking brake OFF
What buses and/ or components eill be powered when the ADG is supplying power?
The ADG powers the AC ESS BUS and the ACMP(Alternating current motor pump) 3B hydraulic pump.
What airspeed limitations exist for the ADG wet or dry?
-200
Wet: 250KIAS
Dry: Vmo/Mmo
-700/900:
Vmo/Mmo
After restoring normal AC power, how is the AC ESS BUS transferred to the normal AC distribution system?
Pressing the PWR TXFR OVERRIDE switch on the ADG panel
Name the sources of DC power
- 5 TRUs
- 2 NiCad batteries
What are the minimum voltage requirements on the APU and MAIN batteries prior to starting the APU?
-22 Volts
Ground operations with only DC power are limited to how long?
-5 minutes
What is the amp rating for the TRU’s in the 200?
100 Amps
What is the amp rating for the TRU’s in the 700/900?
120 amps
Is TRU #2 capable of supplying power to DC BUS 1 in the event of TRU 1 failure?
Yes, both DC BUS 1 and DC BUS 2 can be powered by the other TRU through tie connectors.
Are all DC ties capable of being closed manually?
No;
TIE 1 and tie 2 can be closed manually or automatically.
ESS TIE can only be closed manually
How many hydraulic systems does the CRJ have?
3
How can Skydrol hydraulic fluid be easily identified?
Purple color
How many hydraulic pumps does the CRJ have? How are the operated?
- There are 6 total pumps (two per system)
- System 1 and 2 have an engine driven pump and an electrical pump.
- System 3 has two electric pumps.
What is the normal pressure range for the hydraulic system?
-2800-3200psi
Below what pressure value does the HYD LOW PRESS caution message display?
When the respective system pressure is <= 1800psi.
What is the normal quantity range for the hydraulic fluid reservoirs?
Between 45%-85%
How is the hydraulic fluid cooled?
RAM AIR
In cruise, which hydraulic pumps are operating assuming all systems are operating normally?
- 1A
- 2A
- 3A
On final approach, which hydraulic pumps are operating.
All A and B pumps, 6 in total
Explain hydraulic logic
Each pump is powered by the cross side generator. The system 3 pump is powered by either GEN 1 or GEN 2.
Does the ACMP 3B switch have to be selected ON in order to operate if the ADG is deployed and supplying electric power?
No; When the ADG deploys, it will automatically power pump 3B regardless of switch position.
Will ACKP 1 and 2 turn on automatically when their respective engine drive pump has failed?
No. You need cross side logic and flaps >0.
How can you close the HYD SOV’s in the 200, 700, 900?
- All three variants will close when the corresponding ENG FIRE PUSH switch is selected.
- The 700/900 has dedicated HYD SOV switches.
Which hydraulic system operates the OUTBOARD BRAKES?
Hydraulic system 2
Which hydraulic system operates the inboard brakes?
Hydraulic system 3
Which stages of bleed air are used by the 200?
10th stage: Used for PACKs and engine starting
14th stage: Uses air for anti ice and thrust reversers
What is the 10th stage bleed air used for (CRJ 200)?
- Engine Starting
- Air-conditioning
- Pressurization
What is the 14th stage used for?
- Anti-ice
- Thrust reverser operation
CRJ 200, what sources can provide air to the 19th stage bleed manifold?
- Engines
- APU
- External Air Source
On the CRJ 200, what sources can provide air to the 14th stage bleed manifold?
-Engines only
How are the 10th stage bleed valves operated?
-Electro-pneumatic
How are the 14th bleed valves controlled?
-Electro-pneumatic
The 10th stage beeps valves fail in what position?
Closed
The 14th stage bleed valves fail in what position?
Open
Describe the APU interlock protection
- There is a check valve in the APU bleed air duct that prevents back flow.
- The APU LCV is interlocked with the L and R 10th stage bleed valves and the 10th stage ISOL valve. If the LCV is open while any of those are selected open, the LCV will automatically close to protect the APU.
How does the 200 detect bleed leaks in the 10th stage manifold?
Dual loop overheat protectors
How does the 200 detect bleed leaks in the -4th stage manifold, including the leading edge of the wing?
- Single loop overheat detectors
- Thermal switches in the wing
During engine start sequence, which 10th stage bleed valves automatically open?
- Air turbine starter
- L and R 10th stage SOV’s
- 10th stage ISOL valve
True or False? when the engine fire push switch light is pressed in it will close all associated 10th and 14th stage bleed valves?
True
Under what conditions will the BLEED MISCONFIG caution appear on the 200, 700, 900?
- 200:
- Gear down or flaps >0.
- 10th stage SOV open (engines supplying AC)
- Wing and/or cowl selected ON.
700/900:
- Incorrect bleed configuration in manual mode. - APU is manually selected as bleed source - Wing or cowl switches selected ON
