Chapter 3 Anti ice, Rain Flashcards
What can happen if wing anti ice (WAI) is used above FL350?
Cabin pressure can be lost as well as ‘BLEED TRIP’ OFF. (FCOM SP.16.11)
When is CSFF (cold soaked fuel frost) allowable?
If all of the following conditions ARE met:
• Ambient air temperature is at or above +4°C+39°F
• There is no precipitation or visible moisture (rain, snow, drizzle, or fog with less than 1 mile visibility)
• Tank fuel temperature is at or above -16°C, +3°F
• All leading edge devices, all control surfaces, tab surfaces, winglet surfaces, and control surface balance panel cavities must be free of snow, ice and frost.
If all of the above conditions ARE NOT met, takeoff with light coatings of frost, up to 3 mm thick, on lower wing surfaces due to cold fuel is allowable; however, all leading edge devices, all control surfaces, tab surfaces, winglet surfaces and control surface balance panel cavities must be free of snow, ice and frost. If the frost on the lower surface is greater than 3 mm thick, all snow, ice and frost on the wings must be removed using appropriate deicing/anti-icing procedures.
What must the F/O check when switching on Probe heat switches?
… that all probe heat lights are extinguished.
Can the WAI be used for de-icing?
Yes
Should the engine anti ice be used for de-icing or anti icing?
Anti
What happens to your IAS buffets when WAI or EAI is turned on?
SMYDS sets stall warning logic for icing conditions.
If only EAI was used, the logic disappears when EAI is turned off.
Stick shaker logic remains set for icing conditions for the remainder of the flight if WAI is used, regardless of subsequent WING ANTI–ICE switch position.
(FCOM 3.10.7)
What indication can be used to indicate icing conditions?
Ice accumulation on the flight deck window frames, windshield center post, or on the windshield wiper arm
When PROBE HEAT switches are placed to auto, when is the Probe system heated?
Power is automatically supplied to both A and B probe heat systems when either engine is running.
Does the ‘Engine Bleed’ valve switch have to be ON for Engine anti ice to work?
No.
What causes the amber COWL ANTI–ICE light to illuminate?
Exceeded pressure ONLY (>65 psi) NG’s only.
On CL, OVER TEMP WILL ALSO TRIGGER
With WAI ON, when will the valves automatically close?
If either engine thrust is above the takeoff warning setting or either temperature sensor senses a duct overtemperature.
Does duct temperature and thrust setting logic work in flight in controlling WAI valve operation?
No
How long before take off must window heat be turned ON?
10 min
Are windows R3&L3 heated?
No
Are the static ports heated on the NG?
No (FCOM 3.20.4)
Which five systems priovide anti ice and rain protection?
- Flight Deck Window Heat
- Windshield Wipers
- Probe and Sensor Heat
- Engine Anti-Ice System
- Wing Anti-Ice System
(FCOM 3.20.1)
What do the amber ‘OVERHEAT’ Lights on the overhead panel (windows) indicate?
Overheat condition is detected or if electrical power to window(s) is
interrupted. (FCOM 3.10.1)
During preflight, you notice onr of the Window Heat ‘ON’ ( or AMBER ‘OFF’ lights illuminate (AN2)), Light extinguish (INU). Whats the most likely reason?
The system (window) is at the correct temperature. (FCOM 3.10.2)
On the Window heat panel, what will pressing the OVHT button do? What is the correct procedure?
OVHT � simulates an overheat condition. (FCOM 3.10.2)
1. Turn the window heat switches on
2. Press the OVHT button
3. The ‘ON’ light should extinguish
(FCOM SP.3.4)
On the Window heat panel, what will pressing the PWR TEST button do? What is the correct procedure?
Provides a confidence test. (FCOM 3.10.2) by verifying operation of the window heat system.
Note: The test may be accomplished when any of the window heat ON lights are extinguished and the associated WINDOW HEAT switch is ON. Do not perform the power test when all ‘ON lights are olliminated (OFF lights are extinguished on AN2).
What should be done If any of the ‘ON’ lights on the window heat panel remains extinguished in flight?
The window heat system is inoperative. Observe the maximum airspeed limit of 250 kts below 10,000 feet.
Can you perform the power test when all ON lights are
illuminated (OFF lights are extinguished on AN2)?
When is the PWR TEST normally completed?
No (FCOM SP.3.4)
When any of the window heat ON lights are extinguished
and the associated WINDOW HEAT switch is ON. This is normally in flight as engineers should attend on the ground if the window heat isnt receiving power. (SP.3.4)
What does the TAT TEST Switch do?
Electrical power is applied to TEMP PROBE on the ground. (FCOM 3.10.4)
What does it mean if a Probe Heat Light Illuminates amber?
Related probe is NOT heated. (FCOM 3.10.4)
Note: If operating on standby power, probe heat lights do not indicate system
status.
What does an amber “cowl anti ice” light indicate?
Indicates an overpressure condition in duct downstream of
engine cowl anti�ice valve. (FCOM 3.10.5)
What indicationss should you see when when engine anti ice is turned on?
- Green TAI indication shows on the engine display
- Stall speed (Barber pole- if visible) will increase.
- “COWL VALVE OPEN” light indicates DIM blue (after initially changing bright blue)
What does window “arcing” mean?
Arcing means, the formation of an electric arc - Window arcing is when electric elements inside the cockpit window for anti and de-icing/fogging purposes, short circuit.
What does a constant bright blue VALVE OPEN (COWL VALVE for EAI) light indincate?
Cowl anti�ice valve is not in position indicated by related
engine anti�ice switch.
How many elevator pitot probes are there?
2 (FCOM 3.20.1)
How many pitot probes are there?
Five. Two on the elevaotr and three on the front of the fuselage. (FCOM 3.20.1)
Is window nr 3 heated?
Window number 3 is not electrically heated on INU & 8TG, however A conductive coating on the inner glass pane of window number 3 permits electrical heating to prevent fogging on AN2. (FCOM3.20.2)
What will the window heat temperature controller do incase it senses an overheat condition?
Power to window numbers 1 and 2 is automatically removed.
Are all Pitot tubes heated on standby power?
No, only the captains Pitot probe is heated on standy power. (FCOM 3.20.5)
How is each cowl anti�ice valve controlled and actuated?
Electrically controlled and pressure actuated (FCOM 3.20.5)
Will the Vref set in the CDU for approach, adjusted simultaneously with the stall warning logic for icing conditions, if anti ice is used ?
No, Vref will need to be adjusted manually as per FCOM NP.21.47, for icing conditions.
Note:
FLAP15 LANDINGS ONLY:
If any of the following conditions apply, set VREF ICE = VREF
15 + 10 knots:
� Engine anti�ice will be used during landing
� Wing anti�ice has been used any time during the flight
� Icing conditions were encountered during the flight and the
landing temperature is below 10�C.
When VREF ICE is needed, the wind additive should not
exceed 5 knots.
(FCOM 3.20.5 & )
What is Vref ICE and when is it used?
If a FLAP15 landing is necessary for perfomrance in icing conditions or WAI was used.. VREF = VREF15 + 10kts.
Occasionally, a non-normal checklist instructs the flight crew to use a VREF ICE. When VREF has been adjusted by a NNC, this becomes the VREF used for landing. This VREF does not include wind additives. For example, if a non-normal checklist specifies �Use flaps 15 and VREF 15 + 10 knots for landing�, the flight crew would select flaps 15 as the landing flaps and look up the VREF 15 speed in the FMC or QRH and add 10 knots to that speed.
(FCOM 3.20.5 & FCOM NP.21.47 & FCTM 1.21)
When using Vref ICE for a flap 15 landing, what is the minimum and maximum permissible wind additive ?
5 kts.
What do the amber COWL ANTI�ICE lights indicate?
Excessive pressure in the duct leading from the cowl anti�ice valve to the cowl lip. (FCOM 3.20.5)
The area’s does the wing anti�ice system provides protection for?
The three inboard leading edge slats ONLY. (FCOM 3.20.6)
What happens to the WAI valves if the switches are on and take off thrust or higher is set during ground operations?
Both valves close if either engine thrust is above the takeoff warning setting or
either temperature sensor senses a duct overtemperature. The valves automatically reopen if thrust on both engines is reduced and both temperature sensors are cool. (3.20.7)
Note: The WING ANTI�ICE switch automatically trips OFF at lift�off when the
air/ground sensor goes to the air mode.
Will the thrust setting logic automatically close the WAI valves in flight if the thrust levers are set above take off power?
No, duct temperature and thrust setting logic are disabled and have no effect on control valve operation in flight. (FCOM3.20.7)
Where are the AIR-GROUND SAFETY SENSORS located?
Landing gear. (FCOM3.20.7)
