Anti-Ice, Rain Flashcards
Window OVERHEAT Lights
illuminate yellow when Overheat condition is detected
Note: also illuminate if electrical power to window(s) is interrupted.
Window Heat OFF Lights
Illuminated amber when: - Switch is OFF or - an overheat is detected or - a system failure has occurred or - system is at correct temp or extinguished = window heat is being applied to the selected windows
Probe Heat Lights
related probe not heated
IF: operating on standby power, probe heat lights do not indicate system status
COWL ANTI-ICE lights
indicates an overpressure condition in duct downstream of engine cowl anti-ice valve (excessive pressure in the duct leading from the cowl anti-ice valve to the cowl lip)
COWL VALVE OPEN lights
Bright Blue: related cowl anti-ice valve is in transit, or cowl anti-ice valve position disagrees with related ENGINE ANTI-ICE switch position (amber TAI illuminates on the CDS after a short delay).
DIM BLUE: related cowl anti-ice valve is open (switch ON)
Extinguished - related cowl anti-ice valve is closed (switch OFF)
ENGINE ANTI-ICE Switches
ON:
- related cowl anti-ice valve is open (which allows engine bleed air to flow through the cowl anti-ice valve for cowl lip anti-icing)
- stick shaker logic is set for icing conditions (adjusts stick shaker and minimum maneuver speed bars on the airspeed indicator). Note: FMC displayed VREF is NOT adjusted automatically.
- Green TAI indication shows on the engine display
OFF:
- related cowl anti-ice is closed
- stick shaker logic returns to normal *if wing anti-ice has not been used in flight
- Green TAI indication on the engine display extinguishes.
Wing Anti-Ice VALVE OPEN lights
Blue Bright: related wing anti-ice control valve is in transit, or related wing anti-ice control valve position disagrees with WING ANTI-ICE switch position
DIM: related wing anti-ice control valve is open (switch ON)
Extinguished: related wing anti-ice control valve is closed (switch OFF)
WING ANTI-ICE Switch
OFF - wing anti-ice control valves are closed
ON in the air:
- both wing anti-ice control valves are open
- stick shaker logic is set for icing conditions (stick shaker logic remains set for icing conditions for the remainder of the flight, regardless of subsequent WING ANTI-ICE switch position.)
- Duct temperature and thrust setting logic are disabled and have no effect on control valve operation in flight.
- Valve position is monitored by the blue VALVE OPEN lights.
ON on the ground:
- switch trips OFF at lift-off (when the air/ground sensor goes to the air mode)
- wing anti-ice control valves open 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
What window(s) does the FWD WINDOW HEAT switch control?
Window #1
What window(s) does the SIDE WINDOW HEAT switch control?
Window #2 / #3 (if heated, otherwise only #2)
Temperature controllers maintain what window(s) ?
What happens if an overheat condition is detected?
Temperature controllers maintain windows #1/2 at the correct temperature to ensure maximum strength of the windows in the event of a bird strike
Power to windows #1/#2 is automatically removed if an overheat condition is detected.
Thermal Switches control what window(s)
Window #3, open and close to maintain the correct temperature. (Note: this does not apply to some aircraft that do not have a heated window 3)
Pitot probes, the TAT, and the alpha vanes are heated how?
electrically
When on standby power what probe(s) are powered?
only the captains pitot probe is heated, (however the CAPT PITOT light does NOT illuminate for a failure).
Engine bleed air thermal anti-ice prevents the formation of ice on the ?
Engine cowl lip / 3 inboard leading edge slats
Each cowl anti-ice is (blank) controlled and (blank) actuated
electrically / pressure
If the engine anti-ice is moved to OFF what happens?
Stall warning logic, airspeed indications, and min maneuver speed on the airspeed indicator return to normal as long as wing anti-ice has NOT been used
The wing anti-ice system provides protection for what? what doesn’t it protect?
protection for the 3 inboard leading edge slates with bleed air.
DOES NOT protect the leading edge flaps or the outboard leading edge slats
The wing anti-ice control valves are powered how?
AC motor-operated
What happens at liftoff if the WING ANTI-ICE switch is on?
The WING ANTI-ICE automatically trips off when the air/ground sensor goes to the air mode
Positioning the WING ANTI-ICE switch to ON in flight does what?
Opens both control valves
sets stall warning logic for icing conditions
Window HEAT ON lights
Illuminated green when window heat is being applied to the selected window(s)
Extinguished when:
- Switch is OFF or
- an overheat is detected or
- a system failure has occurred or
- system is at correct temp
When I pull the WINDSHIELD AIR knob, what happens?
supplies conditioned air to #1 windows for defogging.
What are the Windshield Wiper selector positions/times?
PARK - turns off wiper motors and stows wiper blades
INT - 7 second intermittent operation
LOW - low speed operation
HIGH - high speed operation
What are the PROBE HEAT Switches positions?
ON - power is supplied to heat related system
AUTO - power is automatically supplied to both A and B probe heat systems when either engine is running.
What does the TAT TEST Switch do?
When pushed, electrical power is applied to TEMP PROBE on the ground.
What are the Thermal Anti-Ice Indications (TAI) and where is this displayed?
Illuminated:
- Green - cowl anti-ice valve(s) open.
- Amber - cowl anti-ice valve is not in position indicated by related engine anti-ice switch.
Displayed on the engine display (N1 indications)
Flight deck windows have conductive coatings where?
Windows #1 and #2 have a conductive coating on the OUTER glass pane which permits electrical heating (to prevent ice build-up and fogging). Window #3 either has a coating on the INNER glass pane for fogging, or not electrically heated at all, depends on the plane.
What will happen if windshield wipers are operated on a dry windshield?
Windshield will scratch
How are the static ports heated?
They are NOT.
Where does the bleed air flow after it’s been used to heat the 3 leading edge inboard slats during wing anti-icing?
it is exhausted overboard.
What position can the leading edge inboard slats be in and still have the wing anti-ice system be effective?
Any slat position.
