EJET SYSTEMS QUESTIONS (AQP - PRE-CLASS) Flashcards
On the CVR/DVR how much time does it have for recording?
120 Minutes of Datalink
120 Minutes of communication (among ourselves)
25 flight hours of the aircraft
What does the IDG light mean?
It means “HOTLOP” High Oil Temperature, or Low Oil Pressure for the IDG. Letting us know which IDG should be disconnected
What are the ratings of the IDG?
115 Volt, 40 KVA, 400 HZ, 3 phase
Achieved by a constant speed drive going at 12,000 RPMs
What does the IDG power?
IDG 1 powers the AC BUS 1
IDG 2 powers the AC BUS 2
What is the bus priority for powering the airplane?
“ONSIDE, INSIDE, OUTSIDE, OFFSIDE”
- Onside IDG
- APU generator
- GPU generator
- Opposite IDG
Can the IDG power both buses?
Yes, if we lose an engine the remaining IDG will power both buses (thru system logic) until the APU comes online, which will power the failed side.
What does the AVAIL light mean on the GPU button?
Proper Phase, Voltage, Frequency (to connect the GPU to the AC BUS TIE)
What will happen with the AC BUS TIE 1 OPEN knob selection?
Isolates the AC BUS 1 from AC BUS 2 (by opening the AC BUS 1 tie contactor)
What will happen with the AC BUS 2 TIE OPEN switch?
Isolates AC BUS 2 from AC BUS 1 (by opening the AC BUS 2 TIE CONTACTOR)
What is BATT 2 used for?
Only for APU start. it comes off the electrical grid to start the APU thru the APU START BUS
What are the ratings of the BATTERIES (BATT 1 and 2)?
22.8 Volts, 27 amps
When will electrical and pneumatic power be available with APU as the source?
95% plus 3 seconds
What is the APU rated at?
115 Volts, 40 KVA, 400 hz
When will the APU automatically shut down in-flight vs. on ground?
“UFO SHELF”
In-air/ground:
- APU underspeed
- FADEC critical Fault
- APU Overspeed
On-Ground:
S - Sensor Fail H - High Oil Temperature E - EGT over temperature L - Low Oil Pressure F - APU Fire
If Batteries are the only power on the aircraft how long do we have?
10 Minutes of power for aircraft essential systems (if RAT failed)
When does the BATT 1(2) OVERTEMP come on?
When batteries reach a temperature above 70 degrees C for at least 2 seconds.
What is the minimum battery temp for starting the APU?
-20 degrees C
What equipment/components are on the HOT BATT BUS 1?
- Fuel
- Hydraulics
- Pneumatics
- 1A/2A
- Fire Handle (extinguishing)
- Engine Servicing
- Cabin service lights
What equipment/components are on the HOT BATT BUS 2?
- Fuel
- Hydraulics
- Pneumatics
- 1B/2B
- Fire Handle (extinguishing)
- Engine servicing
- Fueling panel (refuel/refuel)
- Potable water servicing
How many TRUs do we have?
3 TRUs (TRU 1, TRU 2, TRU ESS)
What is the purpose of the TRU?
To convert 115 Volts of AC to 28 Volts of DC
What are the TRUs rated at?
300 amps
What does TRU 1 power?
DC BUS 1 DC ESS Bus 1 DC Ground service bus HOT BATT BUS 1 Battery 1 Charging
What does TRU 2 power?
- DC BUS 2
- HOT BATT BUS 2
- DC ESS 2 bus
- Battery 2 charging
What does TRU ESS power?
DC ESS bus 3
When would we need to use the DC GPU?
When BATT 2 is no longer available or when battery temperature is below -20 degrees C
How much power does the DC GPU provide?
24-29 volts of DC power
What is the purpose of the Inverter?
To convert 28 volts of DC power to 115 volts of AC power, when there is no other AC source of power.