Electrical System

Question 1

The left PFD, ND, and FMC are normally powered by?

AOM Vol II, Ch 6

Answer 1

• The APU Standby Bus.

Question 2

Under normal operation, what powers the main and APU Standby busses?
(AOM Vol II, Ch 6)

Answer 2

• Main Standby is powered by AC 3.

* APU Standby is powered by the Captain’s Transfer Bus, which is normally powered by AC 3.

Question 3

What is the source of power to the APU Standby bus with a loss of AC bus 3?
(AOM Vol II, Ch 6)

Answer 3

• The Captain’s Transfer bus, which is now powered by AC 1.

Question 4

What causes DISC to illuminate in the IDG Disconnect Switch? (AOM Vol II, Ch 6)

Answer 4

• High IDG Oil Temperature.
• Low IDG Oil Pressure.
• Uncorrectable frequency fault.

Question 5

Do the AC BTBs and DCIRs open at any time when there is no cockpit annunciation?
(AOM Vol II, Ch 6)

Answer 5

• Yes, during a triple autopilot coupled approach.

Question 6

What will power the Main Deck Cargo Handling bus with both APU generator 2 and External Power 2 available?
(AOM Vol II, Ch 6)

Answer 6

• External Power 2 has priority over the APU generator.

Question 7

You are being released to a destination where a Category III approach is to be conducted. Enroute, the number 4 Generator has been disconnected. Can you still conduct a category III approach?
(QRH, Ch AP)

Answer 7

• Yes.

Question 8

How can you manually open the number 4 DCIR?

AOM Vol II, Ch 6

Answer 8

• Open the number 4 bus tie switch.

Question 9

You are conducting your cockpit setup. Inspecting the overhead maintenance panel, you notice that the number 1 generator field OPEN light is illuminated. There are no discrepancies in the logbook. How can you reset the generator field?
(AOM Vol II, Ch 6)

Answer 9

• Cycle the number 1 generator control switch off, then on.

Question 10

The aircraft is dark. External power is available to the left side of the Synch Bus. Can you light your path to the cockpit? How?
(AOM Vol II, Ch 6) (AOM Vol II, Ch 1)

Answer 10

• Yes.
• First, connect the Ground Service Bus to the Ground Handling Bus with the switch adjacent to the L1 door.
• Second, select the Flight Deck Access Light switch next to the Ground Service switch to ON.