Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

UAL 787 SV Study Questions Nov 23 > Electrical > Flashcards

Electrical Flashcards

1
Q

The bus power control units provide electrical load management when the aircraft is operating on:

A. Engine starter generators only.
B. Aft external power only.
C. Fwd external power only.
D. Any available electrical power source.”

A

D. Any available electrical power source.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

If the permanent magnet generators are not available, the flight control electronics receive power from the:

A. F/O’s flight instrument bus.
B. 28v DC system and main battery.
C. Captains flight instrument bus.
D. Directly from the EEC electronics units.”

A

B. 28v DC system and main battery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the minimum number of external power sources required for an external power ONLY engine start?

A. Two (Either forward and the aft external).
B. Three.
C. Engine start is not available on external power only.
D. Two (L&R FWD).

A

D. Two (L&R FWD).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The ground handling mode is powered when ______ if no other power source is available.

A. Both forward external power sources are in use (ON).
B. Either FWD external power is connected (AVAIL).
C. Only AFT external power is connected (AVAIL).
D. The battery switch is ON.

A

B. Either FWD external power is connected (AVAIL).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The generator drive may disconnect automatically _________ .

A. Only on the ground.
B. Due to excessive frequency variations.
C. Due to bearing failure.
D. Depending on the fault condition detected.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How can the flight crew determine circuit breaker status?

A. Check the CBIC display.
B. Check the Status page display.
C. Check the Electrical synoptic.
D. Open CB’s automatically display on EICAS.”

A

A. Check the CBIC display.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the purpose of the permanent magnet generators (PMGs)?

A. Powers the Captains standby electrical system.
B. Powers the hot battery buss and main battery charger.
C. Powers the flight control electronics.
D. All the above.

A

C. Powers the flight control electronics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The main battery provides power to the following:

A. Electric braking (as backup source).
B. The Captains Flight instrument bus until RAT deployment.
C. Towing and refueling operations.
D. All the above.

A

D. All the above.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The illuminated “AVAIL” light on the FWD or AFT external power switches indicate:

A. External power is plugged in and voltage and frequency are within limits.
B. External power is plugged in and is being used.
C. AC busses have lost all power and are looking for an external power source.
D. The system is available for external power to be plugged in.

A

A. External power is plugged in and voltage and frequency are within limits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which of the following is true with regard to loss of two Starter Generators (SG’s) in flight?

A. APU will Auto Start.
B. RAT will deploy.
C. First Officers flight instruments will be unpowered.
D. Some load shedding will occur.

A

D. Some load shedding will occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which type of circuit breaker can be reset using the CBIC, either on the ground or in flight?

A. Electronic circuit breakers.
B. Thermal circuit breakers.
C. Only cabin related circuit breakers.
D. All breakers can be reset using the CBIC, but only with the concurrance of TOMC.

A

A. Electronic circuit breakers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which of the following conditions will cause the RAT to deploy automatically in flight?

A. Loss of the R1 bus.
B. Loss of the L2 bus with BAT.
C. Loss of two starter generators.
D. Loss of all electrical power to the Capt and FO’s flight instruments.

A

D. Loss of all electrical power to the Capt and FO’s flight instruments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

To remain within the capacity of the available power sources, ____ will occur.

A. Load Inhibit.
B. Non-essential circuit breakers will open as needed.
C. APU autostart.
D. Load Shedding.

A

D. Load Shedding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If a loss of all electrical power to Capt’s and FO’s flight instruments occurs in flight, the _____ provides Standby Power until RAT deployment.

A. Main battery.
B. APU battery.
C. PMG’s.
D. Dedicated standby power bus batteries.

A

A. Main battery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which of the following indications will display during automatic load shedding?
A. LOAD SHED is displayed next the affected equipment symbol on the appropriate system synoptic.
B. “LOAD SHED” EICAS message displays.
C. A list of affected aircraft systems on the electrical synoptic.
D. Both A and C are correct.

A

D. Both A and C are correct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Inflight, with only one starter generator available ______?

A. Engine anti-ice is no longer available.
B. Power remains available to critical and essential equipment.
C. The standby inverter is powered.
D. All CAC’s go to high flow to maintain pressurization.”

A

B. Power remains available to critical and essential equipment.

17
Q

With the airplane unpowered on the ground, pushing the battery switch to ON:

A. Begins the left and right CCR start-up process.
B. Powers the left inboard and outboard displays.
C. Powers the left TCP.
D. Begins the left CCR start-up process.”

A

D. Begins the left CCR start-up process.

18
Q

If a drive disconnect switch is pushed, with engines operating:

A. The starter/generator is disengaged from the engine.
B. The “ELEC GEN DRIVE” EICAS message displays.
C. Maintenance action will be required to reconnect the starter/generator.
D. All of the above.

A

D. All of the above.

19
Q

If both FWD external power are powering the main AC busses, when the APU starter/generators become available:

A. The APU generator power is automatically applied when all external power is selected OFF.
B. The APU generators automatically replace all external power sources.
C. The APU generator powers the R1 and R2 AC busses & FWD external powers the L1 and L2 busses.”
D. APU generator power must be manually selected ON.

A

B. The APU generators automatically replace all external power sources.

20
Q

After the APU is up to speed and has replaced the external power, what happens if external is reselected to ON?

A. the APU reverts to AVAIL and the FWD external powers the electrical system.
B. The APU powers the high load busses and the FWD external powers the 115v busses.
C. The APU generators and FWD external power parallel and share the load.
D. Nothing, the APU generators have priority and won’t allow selection of any external power until the APU is selected OFF.

A

B. The APU powers the high load busses and the FWD external powers the 115v busses.

21
Q

With the APU running, and both engines running with all four starter/generators operating, when will the APU begin to power all or part of the aircraft?

A. Immediately, it will parallel with the other generators and share the load.
B. With the loss of one or more of the starter/generators.
C. At engine shut down at the gate.
D. Both B. and C. are correct.

A

D. Both B. and C. are correct.

22
Q

The Towing Power panel provides power for ___.

A. Capt’s audio control panel, Capt’s flight interphone.
B. Brakes, Navigation lights.
C. Radio communications.
D. Both A and B are correct.

A

D. Both A and B are correct.

23
Q

If any engine generator fails, how is power provided to it’s associated main AC bus?

A. The lost main AC bus is now powered by another main AC bus.
B. The RAT deploys & powers the AC bus.
C. The main battery will energize the AC inverter to power the bus.
D. The PMG’s will provide backup power to the associated bus.”

A

A. The lost main AC bus is now powered by another main AC bus.

24
Q

The Large Motor Power Distribution System (LMPS) powers ______ .

A. CAC’s.
B. Hydraulic pumps.
C. Power for APU and Engine starting.
D. All the above.

A

D. All the above.

25
Q

The PECS system provides _____ .

A. Heat dissipation for the Large Motor Power System (LMPS).
B. Cooling for the FWD and AFT passenger entertainment systems.
C. Cooling for the left and right CCR’s.
D. Additional cooling to the FD crew rest area.

A

A. Heat dissipation for the Large Motor Power System (LMPS).

26
Q

After landing, PECS cooldown begins when ____?

A. Packs are shutdown.
B. Hydraulic EMP’s are shutdown.
C. IRS’s are selected OFF.
D. Packs AND hydraulic EMP’s are shutdown.

A

D. Packs AND hydraulic EMP’s are shutdown.

27
Q

The Starter/Generators (SG’s) _____ .

A. Are variable frequency and utilize a CSD to provide stable output.
B. Are variable frequency and are directly connected to the engine gearbox.
C. Ganged in pairs through a hydro/electric motor drive.
D. Are variable frequency, and utilize the engine variable stator vanes to control output.

A

B. Are variable frequency and are directly connected to the engine gearbox.

28
Q

The RAT provides:

A. Standby electrical power.
B. Backup hydraulic pressure.
C. Alternate pneumatic pressure.
D. A and B are correct.

A

D. A and B are correct.

29
Q

The standby electrical system consists of:

A. The Standby Inverter.
B. The flight control electronics system.
C. The Main battery and the RAT generator.
D. All the above.

A

C. The Main battery and the RAT generator.

30
Q

Primary and backup power for the brake system is provided by:

A. 28vdc power for the primary system and the main battery for the backup source.
B. The R1 AC bus for the primary source and the Capt’s Flight instrument bus as the backup source.
C. The F/Os Flight instrument bus as the primary source and the APU battery as the backup source.
D. Main battery for the primary system and 20 minute rechargeable batteries for the backup.

A

A. 28vdc power for the primary system and the main battery for the backup source.

31
Q

The APU generator OFF lights illuminate when:

A. The APU generator is in standby mode.
B. The APU generator power has been replaced by external power.
C. The APU generator control breaker is open.
D. The APU generator power has been replaced by engine starter generator power.

A

C. The APU generator control breaker is open.

32
Q

Which engine can be started using all three external power sources?

A. The left engine only.
B. Either engine, with concurrance of the ground crew.
C. The right engine only.
D. Neither, a ground air cart must be used for an engine start without the APU.

A

C. The right engine only.

33
Q

The aft external power receptacle is located:

A. On the right side of the fuselage below the aft cargo door.
B. On the fuselage, between the main gear doors.
C. On the left side of the fuselage aft of the outflow valve.
D. On the left side of the fuselage aft of the wing.

A

D. On the left side of the fuselage aft of the wing.

UAL 787 SV Study Questions Nov 23 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions