Oral Study Guide Flashcards
Where does the DC service switch get power from
APU battery direct bus
Why do we not leave the airplane in the service configuration using the DC service switch
Drains the APU battery
With the battery master switch on (No AC power established) which screens come online and what is the limitation
- ED1, ED2, ISI
2 5 Minutes (AC fans are not running to cool the screens)
What does the AVAIL illumination on the AC switch light indicate
Correct voltage, frequency, and phase. (115V ac, 400Hz, and 3 Phase)
What does the FAULT illumination of the IDG switch light inidcate
Hi oil temperature and low oil pressure in the IDG
What does the DISC illumination on the IDG switch light indicate
Associated IDG disconnected
To reset, engine has to be off and it can only be reset by maintenance on the ground
How can an IDG be disconnected
Manually or Automatically.
Over temperature or over Torque
Explain the auto disconnect of an IDG
The shaft in the IDG will shear due to over torque or temperature.
What does the illumination of the AC ESS XFER switch light indicate
AC not being provided by AC Bus 1
What does the illumination of the FAIL on the AUTO XFER switch light indicate
BUS fault or generator over current.
Takes generator offline
How many generators are installed on the airplane
4
What does the illumination of the OFF on the AUTO XFER switch light indicate
Disabled the automatic transfer system on the affected side generator
What are the main generators rated at
40KVA
What is the ADG rated at
15KVA
What would cause the ADG to auto deploy in flight
Loss of power on AC BUS 1 and 2
Complete AC power loss
If the ADG is deployed in flight, what does it power
FlASH - Acronym Flaps AC ESS BUS Stab trim CH2 Hydraulic Pump 3B
What is the purpose of the L and R HYD SOV guarded switch lights
Isolate the flow of Skydrol (Hydraulic fluid) to the engine driven pumps
With the hydraulic switches on AUTO/ON, when will the B pumps operate
- In Auto, the B pumps will operate when flaps are out of the ZERO position (Flaps 8+) with at least one operational generator and power to the AC buses
- In ON Mode they will be operating continuously
Taxiing on the left engine (right engine off) flaps up APU running (first flight of the day) switches AUTO/ON which hydraulic pumps are running and how much breaking is available
3A,1A and the inboard brakes only
During normal takeoffs and landings which hydraulic pumps are operating (AUTO/ON)
1A,1B,2A,2B,3A,3B (All of them)
If there are is a failure of an A pump in flight, will a B pump automatically come online AUTO/ON
If the switches are in the ON position Yes they will be on.
If the switches are in the AUTO position No they will not come on in normal cruise flight. Since they flaps are not extended in cruise flight
How many ways can we transfer fuel
Three different ways. Automatically, Manually, and Gravity.
What does the INOP on the boost pump switch light indicate and what does the ON light indicate
INOP - The pump pressure is low or pump has failed
ON - Pump is operating
When do the boost pumps operate
Once they are armed by selecting the boost pump switch light, they will turn ON when starting the engine and when the FSC detects low pressure from the main ejector corresponding to that side. The boost pumps will always operate together
When will the fuel system auto transfer fuel
200lb imbalance between the main (wing) tanks. It will fill the lower tank to level plus 50lbs
What does the illumination of the FAIL on the gravity switch light indicate
Indicates the valve is not in the commanded position
What does the illumination of the FAIL XFLOW switch light indicate
The switch light indicates the valve is not in the commanded position
What happens if you move the WING A/I CROSS BLEED switch from the normal position to FROM LEFT or FROM RIGHT
- Appropriate (opposite of selected) anti-ice isolation valve closes
- Cross bleed valve opens
If you select the BLEED VALVES knob from AUTO to CLSD which valves will close
Closes PRSOV’s for Left and Right engine and APU Load Control Valve (LCV)
If you want to use the APU as your primary bleed source, how would you do that
- Select APU with the BLEED SOURCE selector knob
- Move the isolation toggle switch to open
- Turn the BLEED VALVES selector to MANUAL
First flight of the day, before you start the APU, what must be performed
Fire detection/Firex Monitor test must be completed
What is the minimum battery voltage to start the APU where is the voltage verified
- 22 volts on both APU and Main battery.
- Batteries are verified on the DC ELECTRICAL Synoptic page
(APU Battery powers starter motor for APU, Main battery powers APU ECU for start)
What are the APU start limitations
3 attempts per hour, 2 minute between each attempt
What does the illumination of the PUMP FAIL on the PWR FUEL switch light indicate
APU fuel pump failed
What does the illumination of the SOV FAIL on the PWR FUEL switch light inidicate
APU fuel feed shutoff valve is not in the commanded position
What are the APU priorities
1st Priority is to supply electrical power
2nd Priority is pneumatics
What is the maximum altitude we can use the APU for electrical loading
FL410
What is the maximum altitude for starting the APU
FL370
What is the maximum altitude for bleed air extraction from the APU
FL250
What tank supplies the APU with fuel
Left collector tank
If the APU fuel pump fails, will the APU shut down
No an internal bypass valve opens allowing fuel flow to remain uninterrupted via a high pressure pump
For an unattended APU fire on the ground, what will happen?
On the ground the APU will shut down automatically and five seconds later the FIREX bottle will automatically discharge.
If there is an APU fire in flight, what will happen?
In flight the APU will automatically shut down. FIREX discharge is done by the crew
What are the steps for a normal engine start (APU Assist)
Refer to CFM 4.47
Normal Sequence Right engine then left
1. Trust levers, check at SHUT OFF position
2. ITT less than 120c
L or R boost pump on (L or R BOOST PUMP ON lights and advisory messages come on)
3. Fuel temperature is within normal limits (L or R FUEL TEMP LO caution messages is not displayed)
4. L or R engine START
5. When N2 reaches 20% RPM and ITT is below 120c Left or Right Thrust Lever IDLE (Fuel flow increasing, L or R AUTO IGNITION advisory messages comes on)
6. Starter Cutout Occurs at 50% N2
7. START switch light extinguishes
8. ENGINE START status message extinguishes
During normal engine starts, what kind of protection does the FADEC provide
FADEC will abort for HOT and HUNG START’s. If this happens a L or R START ABORT caution message wil be displayed
Define cold soaked aircraft and what we have to do if an aircraft is cold soaked
Cold soaked is an aircraft that has sat for more than 8hrs below -30c.
Engines must be motored 60 seconds
Thrust reverser actuated until deploy and stow less than 2 seconds
