Anti-Ice, Rain

Question 1

Explain the function of the WINDOW HEAT test switch

Answer 1

OVHT - simulates and overheat condition

PWR TEST - provides a confidence test to verify operation of the window heat system

VOL 2 / 3.1.1 (4)

Question 2

Describe the operation of the four WINDOW HEAT Switches

Answer 2

ON - window heat is applied to select windows(s)

OFF - window heat not in use

Note: window heat only applied to L2, L1, R1, R2 windows

VOL 2 / 3.1.1

Question 3

Explain which equipment is electrically heated with the PROBE heat switches ON

Answer 3

• Associated PITOT PROBE(s)
• TEMP PROBE (Total Air Temperature Probe). **Not heated on the ground unless TAT Test Switch is pushed. **
• Associated ALPHA VANE(s)

Note: Static ports are not heated.
Note: In AUTO, probe heat is powered automatically when either engine is running. We normally move these switches to ON after engine start and to AUTO during the Shutdown Checklist.

VOL 2 / 3.1.4

Question 4

Explain the logic of the wing anti-ice L VALVE OPEN, R VALVE OPEN and the engine anti-ice COWL VALVE OPEN Lights on the overhead panel.

Answer 4

BRIGHT BLUE - Related anti-ice valve is in transit, or anti-ice position disagrees with related ANTI-ICE switch position

DIM BLUE - Related anti-ice valve is open (switch ON)

Extinguished: Related anti-ice valve is closed (switch OFF)

Note: DIM BLUE: valve agrees with switch position (open). BRIGHT BLUE: valve in transit or disagrees with switch position (closed).

VOL 2 / 3.1.5 & 3.1.6

Question 5

Explain the meaning of the illuminated OVERHEAT indication on the window heat panel

Answer 5

An OVERHEAT condition is detected

Note: OVERHEAT lights also illuminate if electrical power to window(s) is interrupted

Question 6

Explain the meaning of an illuminated Probe heat light

Answer 6

• The related probe is not heated

Note: If operating on standby power, probe heat lights do not indicate system status

Vol 2 / 3.1.4

Question 7

Describe the circumstances that would cause the illumination of a COWL ANTI-ICE light

Answer 7

Overpressure condition in duct downstream of engine cowl anti-ice valve (not temp related)

Note: Cowl anti-ice can never be too HOTTTT

Vol 2 / 3.1.5

Question 8

Describe the area of the engine that is heated when anti-ice is used

Answer 8

Engine cowl lip (the metal part on the front of the engine)

Vol 2 / 3.2.5

Question 9

Describe the indications when engine anti-ice is in use

Answer 9

TAI is displayed above N1 digital display

TAI (Green) - cowl anti-ice valve is open

TAI (Amber) - cowl anti-ice valve is not in position indicated by related engine anti-ice switch

Note: TAI = Thermal Anti-Ice

Vol 2 / 3.1.5.1

Question 10

Describe how setting takeoff power and lift-off affects the wing anti-ice system

Answer 10

• Left and right 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

Note: Wing anti-ice control valve open if thrust on both engines is below takeoff warning setting and temperature inside both distribution ducts is below thermal switch activation temperature.

Note: WTF did all that say?? Wing anti-ice isn’t used on the ground because it doesn’t work on the ground…. take-home?

Vol 2 / 3.2.6.1

Question 11

The EXTINGUISHED light logic of the blue wing and engine anti-ice VALVE-OPEN lights indicates that the valve is closed

Answer 11

TRUE

BRIGHT BLUE - in transit or disagree

LIGHT BLUE - agree (valve open)

Extinguished - (valve closed)

ESV- SA: Anti-Ice/Rain

Question 12

The DIM light logic of the blue wing and engine-anti-ice VALVE-OPEN lights indicates that the valve is open

Answer 12

TRUE

BRIGHT BLUE - in transit or disagree

LIGHT BLUE - agree (valve open)

Extinguished - (valve closed)

ESV- SA: Anti-Ice/Rain

Question 13

True or False:
A COWL ANTI-ICE light indicates excessive temperature in the duct

Answer 13

FALSE

The cowling can never be too HOT, only too much pressure

ESV- SA: Anti-Ice/Rain

Question 14

An amber TAI light on the upper display unit indicates that:

Answer 14

the related cowl anti-ice calce is not in the position indicated by the related engine anti-ice switch

ESV- SA: Anti-Ice/Rain

Question 15

The wing anti-ice switch trips to OFF automatically …

Answer 15

at liftoff

ESV- SA: Anti-Ice/Rain

Question 16

The OVHT position of the WINDOW HEAT test switch…

Answer 16

simulates an overheat condition (to test it)

ESV- SA: Anti-Ice/Rain

Question 17

The BRIGHT light logic of the blue wing and engine anti-ice VALVE-OPEN lights indicates that the valve is closed

Answer 17

FALSE

In transit or disagrees. I find this question annoying because you need to know which position the switch is in. If the valve is closed but the switch is on, they disagree which means you’ll have a bright blue light

ESV- SA: Anti-Ice/Rain

Question 18

Describe the operation of the four WINDOW HEAT switches

Answer 18

ON - window heat is applied to select window(s)

OFF - Window heat not in use

There is no auto function with the OFF position.

ESV- SA: Anti-Ice/Rain

Question 19

An illuminated PROBE HEAT light indicates///

Answer 19

Related probe is not heated

ESV- SA: Anti-Ice/Rain

Question 20

True or False:
The total air temperature probe may be tested on the ground with the PROBE HEAT switch off

Answer 20

TRUE

Can only be heated on the ground if the TAT Test Switch is pushed

ESV- SA: Anti-Ice/Rain

Question 21

An illuminated amber OVERHEAT light on the window heat panel indicates…

Answer 21

an overheat condition is detected

ESV- SA: Anti-Ice/Rain

Question 22

The engine anti-ice system heats the:

Answer 22

Engine cowl lip only

This a 737 not an Airbus

ESV- SA: Anti-Ice/Rain