Ice & Rain Protection Flashcards
What sources are used for A/C A/I and Deicing?
- Bleed Air heat
- Electrical heat
What uses bleed air for ice protection?
- Engines lips (HP #10 bleed)
- Outboard Slats (2,3,4 on each wing)
What uses electrical heat for protection?
- Smart probes
- TAT probes
- Windshields
- Water lines
- Pressurization static port
If an engine fails, does the opposite wing and engine receive bleed air?
X-bleed opens automatically when bleed source is lost and opposite wing receives bleed air, failed engine lip does not (engine A/I CV shuts if engine OFF)
How many ice detectors must be working to have ice detection?
One, 2 for redundancy
How long will the deicing system remain on after icing is no longer detected?
5 mins
If icing on the MCDU is set to ‘OFF’ and on takeoff roll icing conditions are encountered, will the deicing system turn on?
Yes at 1700 ft AFE or 2 mins after takeoff whichever happens first
Can the APU be used to provide bleed for anti-ice?
No
What is protected from ice & rain?
- Engine inlets (HP # 10 bleed)
- Wing leading edge
- Smart probes and TAT probes
- Windshields
- Water & waste drain systems
Is the ice protection system automatic?
Yes under normal conditions
Can the pilot override the automatic system?
Yes
How is ice detected?
2 ice detectors
1. Smart probe vibrates,
2. ice accumulates and vibrating freq. changes,
3. sensor element heats
4. Wing and Eng A/I activates
5. Ice melts off probes
6. Probes return to normal conditions
Which bleed is tapped for anti-icing operations?
10th High Stage Valve (HSV)
How is bleed air directed for pneumatic anti-ice for engines and wings?
Engines = Independent
Wings = onside bleed
What happens if there is a single bleed source failure?
Crossbleed automatically opens
How should the MCDU be set if there are icing conditions present on the ground?
ALL
What is set on the MCDU for TATs between 5º and 10º for ice protection?
ENG
What is set on the MCDU for TATs below 5º?
ALL
What does selecting “ALL” on the MCDU provide for ice protection?
Engine A/I = ON while engines are running
Wing A/I = ON at 40 kt wheel speed
How does the failure of one of the 2 power sources affect the windshield heating system?
- On ground = inhibited
- In flight = Left side is heated (right heats if left side fails)
What does the “TIMER” selection on the windshield wiper switch do?
Activates the associated wiper in 8-second intervals
What happens if the wiper is operated on a dry windshield?
- Wiper will stop
- To reset wiper move switch to OFF
When do the smart probes begin heating?
When engines are running
Is there a test for the A/I System?
Yes, but this is a MX task
How should the A/C be configured for deicing?
- Bleeds = OFF
- Packs = OFF
- Stab. Trim = FULL NOSE DOWN
- Flaps = UP
- Engines and APU = ON and OFF
How many AC electrical sources are required for normal windshield heat operation?
2 AC sources
When the batteries are the only electrical source to the aircraft, which ADSP is the heated?
Only ADSP 3
How does the engine anti-ice valve fail?
It fails to the OPEN position, not to be confused with IF ENG shuts down the valve CLOSES to prevent unnecessary engine lip heating to dead engine
