3 Anti-ice, Rain

Question 1

🟧 OVERHEAT
- illuminate when:

Answer 1

overheat detected OR electrical power (to windows) is interrupted

Question 2

WINDOW HEAT 🟧 OFF
- illuminate when

Answer 2

overheat detected, at correct temperature OR system failure has occurred

Question 3

windshield wiper INT

Answer 3

Intermittent operation (7sec/time)

Question 4

Probe heat lights:
Probe heat switch:

Answer 4

• When operating on STANDBY power: do not indicate status (🟧 AUX PITOT)
• AUTO - power automatically applied to both A AND B probe heat system when either engine is running

Question 5

🟧 COWL ANTI-ICE

Answer 5

overpressure condition in duct DOWNSTREAM of Engine cowl anti-ice valve

Question 6

ENGINE ANTI-ICE SWITCHES
- ON
- OFF

Answer 6

ON - stick shaker logic is set for icing conditions
- green TAI shown on EICAS

OFF - stick shaker logic back to no icing conditions IF wing anti-ice not used in Flight
- green TAI extinguished on EICAS

ELECTRICALLY CONTROLLED PRESSURE ACTUATED

Question 7

WING ANTI-ICE SWITCHES
- ON (in AIR)
- ON ( on GND)

Answer 7

AIR - stick shaker logic is set for icing conditions (and will remain like that regardless of switch positions)
GND - wing anti-ice control valve opens if thrust on both engines is below takeoff warning setting and temperature inside both distribution ducts is below thermal switch activation temperature
- control valves close if either engine thrust is above takeoff warning setting OR thermal switch is activated in either distribution duct-> switch remains ON
- switch trips OFF at lift-off

Question 8

window heat
1 and 2
3

switches:

Answer 8

1 and 2: conductive coating on outer glass pane permits electrical heating to prevent ice build up and fogging
3: conductive coating on inner glass permits electrical heating for preventing fogging

FWD WINDOW HEAT SWITCH: 1
SIDE WINDOW HEAT SWITCH: 2 and 3

Question 9

how windows heated

Answer 9

• Temp controllers maintain windows 1 and 2 at correct temperature (for max strength with bird strikes, the power is automatically removed when overheat)
• Thermal switches open and close for windows 3

Question 10

Rain removal system
- consists of:

Answer 10

windshield wiper + permanent rain repellent coating

Question 11

Probe heat on standby power
- what’s stil working

Answer 11

Only Captain pitot probe heat (no standby airspeed pitot probe heat)

Question 12

Wing anti-ice
- powered
- operation

Answer 12

• wing anti-ice valves are AC- motor operated
• air flows first to 3 inboard LE slats than exhausted overboard