Ice and Rain Protection Flashcards
Conditioned air for defogging of the no 1 windows can be routed from which pack?
Pack 1
When would the COWL VALVE OPEN light illuminate bright?
What would the valve being dim mean?
What if the light was off?
When the valve is in transit or when the valve is in disagreement with the switch.
Dim = valve open Off = valve closed
What does TAI stand for on the engine indications?
Thermal Anti Ice
What does a green TAI on the engine indications mean?
Cowl valve open with switch on
What does an amber TAI on the engine indications mean?
The position of the cowl anti-ice valve disagrees with the position of the switch, and will only appear after 8 seconds of this disagreement.
What does the amber COWL ANTI-ICE LIGHT indicate?
That there is an over pressure condition in the duct, downstream of the anti-ice valve.
What pressure would trip the COWL ANTI-ICE light?
> 65 psi
Would you get eng anti-ice with the eng Bleed air switch off?
Yes, because Bleed air for eng anti-ice is taken upstream from the eng bleed valve.
When the eng anti-ice switches are on, what is adjusted?
Stall logic (stick shaker speed, manoeuvre speed bars on pfd etc).
FMC Vref speed is not adjusted automatically.
The COWL ANTI-ICE valves are powered by a…?
What will happen if AC power is lost?
28v DC solenoid.
The valves will spring load closed and engine anti-ice will not be available.
What parts of the wing are protected by wing anti-ice?
3 inboard leading edge slats on each wing.
For the wing anti-ice to function, a Bleed air switch needs to be positioned…?
Why?
On
Because bleed air is taken downstream of the eng bleed valve, so bleed air switch must be open.
What are the wing anti-ice control valves controlled by?
115v AC
Can wing anti-ice be used in the air or on the ground?
Both
What 2 conditions will cause the wing anti-ice control valves to automatically trip closed?
On the ground when thrust levers are advanced for take off
When there is a over temp condition in the wing distribution ducts.
What happens to the stall warning logic after the wing anti-ice is switched off in flight?
Logic remains adjusted for remainder of flight.
How are probes heated?
Electrically
Are static ports heated?
No, because they are flush with the fuselage.
What power do the probe heat elements use?
115v AC
Current detection circuits use 28v DC power
When only will the captains pitot probe be heated?
When on standby power
but no probe heat lights will illuminate, even the capt pitot probe light (on stby power)
How many normal windows and how many eyebrow windows are there?
6 normal
4 eyebrow, left over from Boeing 707 days (stopped in 2005, saves weight and and maint costs)
What is the structure of a non-heated window?
Stretched Acrylic with a gap core
What is the structure of a heated window?
Glass with a vinyl core.
Target window 1 and 2 heat temperature is…?
43 deg c
When will a window overheat trip occur?
If temp exceeds 62 deg c
What does WHCU stand for?
Window Heat Control Unit
What power does the wiper system use?
28v DC
When would you use eng anti-ice and how would you select it?
TAT 10 deg c or less all the way to -40 deg SAT and visible moisture.
Start switches to Cont, then switch on.
When could wing anti-ice trigger a bleed valve trip, causing a possible loss of cabin pressure?
Above FL350 because it demands a lot of Bleed air.
Windows 1L/R are treated with what type of coating?
Hydrophobic
Wiper INT position provides intermittent operation every…?
7 seconds
