Electrics/Fire/Warnings

Question 1

What does each AC power system consist of? (4)

Answer 1

• XFR BUS
• Main Bus
• 2 Galley Buses
• Ground Service Bus

Question 2

What power do the AC generators supply?

Answer 2

3 phase 115V 400Hz AC power.

Question 3

Why will an IDG automatically disconnect?

Answer 3

High oil temperature.

Can also be disconnected manually in the cockpit.

Question 4

Why will SOURCE OFF illuminate inflight?

Answer 4

When respective XFR BUS is powered through BTB system.

Question 5

What is overload protection of the AC system?

Answer 5

Incrementally sheds loads when on single IDG.

Question 6

In what order is AC load shed?

Answer 6

First galley and main bus power on XFR BUS 2. Then XFR BUS 1. If continues, next is the IFE.

Will auto restore if another GEN comes online.

Question 7

What will automatically be load shed inflight if APU GEN sole source?

Answer 7

All Galley and Main Buses, if still overloaded, IFE.

Question 8

Where can APU attempt a full electric load?

Answer 8

On ground.

Question 9

When will the DC Cross Tie Relay open during normal operations? (2)

Answer 9

• When GS captured by either AP or FD.
• BUS XFR switch to OFF

Question 10

What switch will OPEN DC Cross Tie Relay?

Answer 10

Bus XFR switch in OFF position. (Normally in AUTO)

Question 11

When is TRANSFER BUS OFF illuminated?

Answer 11

When respective XFR BUS not powered.

Question 12

When will STANDBY POWER OFF illuminate? (3)

Answer 12

Loss of power to either AC Standby Bus, DC Standby Bus or Battery Bus.

Question 13

What does the Standby Power switch in AUTO allow?

Answer 13

Allows automatic transfer of power to standby buses whether aircraft inflight or on ground.

Question 14

What is the AC Standby Bus powered by in normal conditions?

Answer 14

Transfer Bus 1

Question 15

What is the DC Standby Bus powered by in normal operations?

Answer 15

TR1+2, using TR3 as a backup.

Question 16

In case of AC power failure, what is the AC Standby Bus powered by?

Answer 16

Inverter from the battery. Same as DC STBY BUS.

Question 17

What does the battery remove power from when placed to off?

Answer 17

BATT BUS and Switched HOT BATT BUS when operating normally.

Question 18

What does BATT switch on power?

Answer 18

Switched Hot Battery Bus, and energises relays to provide automatic switching of standby electrical system when normal power fails.

Question 19

When may the BATT DISCHARGE light illuminate in normal operations?

Answer 19

APU Start

Question 20

What does the TR UNIT light illuminate for?

Answer 20

Whenever a TR unit fails on the ground. Inflight, monitors TR1 and a combined TR2+3 failure.

Question 21

What causes the ELEC light to illuminate?

Answer 21

On ground whenever there’s a DC Power System fault or Standby System fault. Inhibited inflight.

Question 22

What will the DRIVE light illuminate for?

Answer 22

Low IDG oil pressure.

Question 23

When will the DRIVE light illuminate? (3)

Answer 23

• Engine fail
• IDG Fail
• IDG disconnect

Question 24

When are the IDG disconnect switches operational? (2)

Answer 24

Electrical power available and engine running.

Question 25

When will the automatic engine generator online function work? (3)

Answer 25

- APU power fails - APU turned off - Switch to IDG on takeoff

Question 26

Where is the DC power usually powered from?

Answer 26

28V DC from the TR’s. No direct control over DC system.

Question 27

What is powered by TR1?

Answer 27

DC BUS 1 and DC STBY BUS. Can be all 3 TR’s if cross tie relay closed.

Question 28

What can be powered by all TR’s of cross tie relay closed?

Answer 28

DC BUS 1, DC STBY BUS and DC BUS 2.

Question 29

What TR is BATT BUS powered by?

Answer 29

TR3, with an alternate source from the battery charger/battery.

Question 30

How can the standby system be powered when the BATT switch off?

Answer 30

Standby power switch must be placed to battery to power standby system from battery.

Question 31

How many TR’s are capable to supply total connected load?

Answer 31

2

Question 32

What the main and aux batteries, and how long will they last?

Answer 32

24V NiCad batteries. Provide standby power for minimum 60 minutes.

Question 33

What indicates if engine overheat detected, or APU DET INOP?

Answer 33

Master Caution

Question 34

What will fault monitoring fire system do if it senses a fault?

Answer 34

Deselect bad loop. Then only selected loop (A or B) can activate warning.

Question 35

What does overheat FAULT light indicate?

Answer 35

Both loops are malfunctioning.

Question 36

What happens when the APU fire switch is pulled up? (3)

Answer 36

- Arms squibs - Close APU Fuel SOV - Trips generator field and generator breaker.

Question 37

Is there a fault warning for wheel well fire detector?

Answer 37

No. Detector only checked by use of OVHT/FIRE TEST switch. Nose wheel well has no fire detection capability.

Question 38

Where is the APU ground control panel?

Answer 38

Right aft main wheel well.

Question 39

What happens if ground control APU fire handle pulled down? (4)

Answer 39

- APU Fuel SOV - Bleed air closes - Inlet closed - Trips APU GEN & Generator breaker.

Question 40

Is there a light to show APU bottle has been discharged?

Answer 40

No. Only discharged from cockpit.

Question 41

When testing OVHT/DET, what do you need to ensure?

Answer 41

Both switches in normal, and all fire system lights are out.

Question 42

What does FAULT/INOP switch illuminate? (4)

Answer 42

- MASTER CAUTION - OVHT/DET - FAULT - APU DET INOP

Question 43

What power will cause wheel well fire light to not illuminate?

Answer 43

Only on DC power.

Question 44

How many extinguisher discharge circuits for engines and APU?

Answer 44

- 2 for engine - 1 for APU

Question 45

What smoke detection installation is used in the cargo compartments?

Answer 45

Dual loop detectors. Single loop available if one fails.

Question 46

What is the power source for cargo compartment smoke detection?

Answer 46

Power source is DC BUS 1 and DC BUS 2.

Question 47

What illumination do you get if smoke detected in cargo compartment?

Answer 47

FIRE WARNING & FWD/AFT CARGO FIRE light.

Question 48

What illumination will you get with a DETECTOR FAULT light?

Answer 48

MASTER CAUTION and OVHT/DET

Question 49

When will DISCH light illuminate?

Answer 49

Once cargo compartment fire light has been armed.

Question 50

How long does cargo compartment discharge take?

Answer 50

30 seconds. Amber DISCH light may not illuminate for up to 30 seconds. Second bottle discharges after 60 minutes.

Question 51

How long is the fire suppression in the hold?

Answer 51

75 minutes.

Question 52

What does proximity switch electronic unit (PSEU) monitor? (3)

Answer 52

- TO Config - Landing gear config - Landing gear - Air/Ground sensor warnings.

Question 53

When is MAINT light inhibited?

Answer 53

From first engine start until 30 seconds after landing.

Question 54

What triggers TO Config horn? (5)

Answer 54

- TE flaps not in F1 - F25 range - TE flaps in skew or asymmetry, or uncommanded motion. - Speedbrake lever not down. - Spoiler control valve is open providing pressurised hydraulic fluid to ground spoiler interlock valve. - Parking brake set. - Stab. Trim not in green band.

Question 55

When will red gear light illuminate because the gear is not down?

Answer 55

Below 800ft AAL and either/both thrust lever at idle.

Question 56

When can use landing gear horn cutout inflight?

Answer 56

Above 200’RA. Located behind start levers.

Question 57

When will landing gear horn operate?

Answer 57

Below 800’ RA with both engines running when either lever between idle and 20 degrees. If OEI, sound if operating engine idle to 34 degrees. (FLAPS UP to FLAPS 10)

Question 58

When can’t the landing gear horn be silenced? (3)

Answer 58

- Below 200’ RA - When gear not down and flaps F15 to F25. - Flaps 25+, will sound regardless of levers.

Question 59

When will landing gear horn sound above 200ft regardless of levers?

Answer 59

Gear not down and flaps 25+.

Question 60

When do GPWS alerts become active?

Answer 60

Below RA activation altitude.

Question 61

What does Amber GPWS PROX INOP mean? (3)

Answer 61

Either GPWS computer malfunction, power loss or invalid inputs.

Question 62

When do you get terrain alert on approach?

Answer 62

Gear and/or flaps not in landing configuration.

Question 63

What are the GPWS inhibit switches? (4)

Answer 63

- Gear - Flap - Terrain - Runway

Question 64

What cancels BELOW G/S light?

Answer 64

Pushing the switch, below 1000ft RA.

Question 65

At what AOB do you get bank angle warning?

Answer 65

35 degrees AOB. Silent until reduced below 30 degrees.

Question 66

What is the enhanced bank angle warning?

Answer 66

Provides red arrows back to S+L when bank exceeds 45 degrees.

Question 67

Below which altitude will you get WINDSHEAR red message and aural warning?

Answer 67

1500ft. On takeoff, begins at rotation.

Question 68

When is terrain clearance floor active?

Answer 68

When close to airport with EGPWS.

Question 69

How long before terrain impact will give look-ahead caution alerts?

Answer 69

40-60 seconds from impact. Repeated every 7 seconds.

Question 70

What will you be presented with prior to a terrain caution with EGPWS?

Answer 70

Density dot pattern of terrain.

Question 71

How long before terrain impact will you get a warning alert?

Answer 71

20-30 seconds. Warning is continuous.

Question 72

What altitude is RAAS armed?

Answer 72

500ft above TDZ elevation.

Question 73

When is on-ground overrun armed?

Answer 73

3 seconds after touchdown, to below 20 knots ground speed, or within 1000ft of runway end.

Question 74

When do you get speed brake not up alert?

Answer 74

Above 80 knots on landing.

Question 75

What has higher priority, GPWS, TCAS or RAAS?

Answer 75

GPWS, TCAS, RAAS

Question 76

When will the RUNWAY INOP light illuminate? (3)

Answer 76

- GPS POS U/S - Not in database - Inhibit switch

Question 77

What are the 3 levels of predictive windshear?

Answer 77

Advisory, caution and warning.

Question 78

When does predictive windshear system operate?

Answer 78

Below 2300ft, but no advisories above 1200ft.

Question 79

How far ahead of aircraft does PWS operate?

Answer 79

3NM

Question 80

When are windshear cautions inhibited?

Answer 80

Between 80kts and 400’ RA.

Question 81

When are windshear warnings inhibited?

Answer 81

Between 100kts and 50’ RA

Question 82

What windshear alerts will you get between 400 and 50’ RA?

Answer 82

Only warnings.

Question 83

What are the priority of warning systems?

Answer 83

GPWS, PWS, TCAS

Question 84

Do windshear advisories have an aural alert?

Answer 84

No. Advisories between 1500’ and 50’.

Question 85

What does TCAS detect with regards to traffic distance and altitude?

Answer 85

30-40NM, above and below 9999ft.

Question 86

What time to impact is TA and RA?

Answer 86

TA - 40 seconds RA - 25 seconds

Question 87

What distance and altitude is OTHER TRAFFIC on TCAS?

Answer 87

Outside 6nm and 1200ft above or below.

Question 88

What is proximate traffic?

Answer 88

Within 6nm and 1200ft.

Question 89

What is the difference between a corrective and preventative RA?

Answer 89

Corrective is change V/S. Preventive is hold V/S.

Question 90

How long to respond to RA?

Answer 90

5 seconds, with 0.25g of force.

Question 91

When are RA’s converted to TA’s on approach?

Answer 91

Below 1000’ RA

Question 92

When is descent and increase descent RA’s inhibited?

Answer 92

Below 1100ft, and 1500ft RA.

Question 93

What altitude are all TA aural alerts inhibited?

Answer 93

Below 500ft RA.

Question 94

How quickly should increase correction RA’s be actioned?

Answer 94

Within 2.5 seconds.

Question 95

Where are each TR’s powered from in the AC system?

Answer 95

TR1 from AC XFR BUS1, TR2 from AC XFR BUS2. TR3 shared between.

Question 96

What does TR UNIT light indicate INFLIGHT or on GROUND?

Answer 96

Inflight, either TR1 or TR2+3 failure. In ground, any TR failure.

Question 97

What are the detector loops powered by ?

Answer 97

BATT BUS

Question 98

What are fire bottles powered by?

Answer 98

HOT BATT BUS

Question 99

What may be needed for WHEEL WELL illumination?

Answer 99

AC power

Question 100

How many loops for APU fire detection?

Answer 100

1 (2 for engines)

Question 101

How many detector loops for cargo hold? Powered by?

Answer 101

2, DC BUS 1+2

Question 102

How long may CARGO FIRE DISCH light take to illuminate?

Answer 102

30 seconds