Electrical & AFCS

Question 1

THE BUS TIE CONTACTOR (BTC) IN THE ACW ELECTRICAL SYSTEM PERMITS:

Answer 1

• If one ACW GEN fails, the other provides power to both ACW busses.
• To provide power to both ACW busses when EXT PWR is used.

Question 2

A/C ON GROUND, DC EXT PWR ON, DC BTC ON “ISOL” :

Answer 2

DC BUS 2 and AC BUS 2 are isolated.

Question 3

A/C IN FLIGHT, ACW GEN 1 FAILS:

Answer 3

ACW SVCE BUS only is shed.

Question 4

ASSUMING NORMAL OPERATION IN FLIGHT, WHEN ARE THE DC EMER BUS AND DC ESS BUS CONNECTED TO THE DC BUS 1 AND/OR DC BUS 2:

Answer 4

Always through BAT CHG and its respective HOT EMER or HOT MAIN BAT BUS

Question 5

IN CASE OF MAIN BAT OVHT WITH MAIN BAT CHG FAULT LIGHT ON, WHAT HAPPENS TO THE BUSSES POWERED BY THAT BATTERY:

Answer 5

The HOT MAIN BAT BUS is lost and DC ESS BAT BUS is powered by DC BUS 1.

Question 6

THE DC SVCE BUS CAN BE POWERED BY:

Answer 6

• DC EXT PWR, only the DC SVCE push- button on the cabin attendant panel has control, even with BAT. SW OFF.
  
  • DC BUS 1 if the DC SVCE/UTLY BUS push-buttons in the cockpit and on the cabin attendant panel are ON.

Question 7

WITH BATTERIES ONLY, AC BUS 1 AND AC BUS 2 ARE:

Answer 7

Never supplied.

Question 8

“BAT” SELECTOR TOGGLE “SW” ON “OVRD” MEANS THAT:

Answer 8

EMER, ESS and STBY BUS are forced to be connected to their respective batteries, overriding all other logics and protections.

Question 9

WHICH ARE THE COMMON “FD” AND “AP” LATERAL (ROLL) MODES OPERATEDBY LATERAL MODES “PB”?

Answer 9

HDG SEL, NAV, APP, BC.

Question 10

IF THE “AP” IS “ON”, WITH THE “FD” ENGAGED IN THE “HDG” AND “ALT” MODE,WHAT HAPPENS IF THE “STBY” “PB” IS PRESSED?

Answer 10

The horizontal and vertical bars disappear from EADI, and the AP returns in BASIC mode on both axes.

Question 11

THE ELECTRICAL SUPPLY OF THE MAIN “AFCS” COMPONENTS IS:

Answer 11

• DC BUS 1 and DC BUS 2 mainly.
• ESS BUS for AP off lights and AP disconnect circuit.

Question 12

WHICH FLIGHT DIRECTOR LATERAL (ROLL) MODES HAVE AN “ARMED” PHASE?

Answer 12

NAV, APP and BC.

Question 13

GND HDL BUS is supplied by HOT MAIN BAT MUS when:

Answer 13

Any of the following:

– The refueling panel is open
– The cargo door control panel is
open
– The passenger door is open

Question 14

A/C ON GROUND, ENGINES RUNNING, EXT ACW PWR SUPPLYING THE BUSSES, WE SELECT ACW BTC ON ISOL:

(which buses are usable / lost?)

Answer 14

ACW BUS 1 and 2 are lost.