Ice Protection/Detection Flashcards
What sources are used for aircraft anti-icing and de-icing?
Bleed air heat and electric heat
What uses bleed air for ice protection?
Engine lips, 3 outboard slats
What uses electric heat for ice protection?
- Pitot Static system (smart and TAT probes)
- Windshields
- Water lines (drain masts)
- Pressurization static port
When are the Air Data Smart Probes and TAT probes heated?
Whenever the engines are running
Where can you find both bleed air pressure and temperature?
Anti-ice synoptic page
What happens when the ICE PROTECTION MODE selector knob is in AUTO
Allows automatic operation of the engine anti-ice system
When will the engine and wing anti-ice systems operate automatically in the event of an ice encounter
When the ICE PROTECTION MODE selector is in AUTO
With the wing ice protection button pushed in it allows what?
Operates automatically or ON based on the ice protection mode selector robot and the ice setting in the MCDU
If an engine fails does the opposite wing and engine receive ice protection?
- Yes, the crossbleed valve opens for the wings
- The failed engine doesn’t receive lip heat
How long will the de-ice system remain on after icing is no longer detected?
5 mins
At what temp are we considered in icing conditions?
SAT (ground) or TAT (flight) is 10C or below with any form of visible moisture and/or visibility of 1SM or less
When do you select “ALL” in the MCDU?
During taxi out and takeoff when SAT is 10 below and icing conditions exist
If ICING on the MCDU is set to OFF and on takeoff roll icing conditions are encountered, will the de-icing system turn on?
Not until 1700’ or 2 mins after takeoff, whichever occurs first
Can the APU be used to provide bleed air for de-icing?
No
What is protected from ice and rain?
Engine inlets, wing leading edge, smart probes, windshields, water drains
May a republic aircraft be flown into a known area of severe icing?
No
Is the icing system automatic?
Yes, under normal conditions
How can you override the system logic and turn the anti-ice system on?
Select ICE PROTECTION selector knob to ON
How many ice detection systems are installed?
- They are completely redundant. One will provide complete detection capability.
How is ice detected in flight?
- Two ice detectors, vibrating sensor elements that change frequency when ice builds up around it
- Once ice is detected, the sensor element heats, the ice melts, normal vibrating characteristics are restored and the heating stops. The cycle repeats as ice rebuilds on the probes
What would happen with the failure of one ice detector?
If the remaining detector senses an icing condition, the system automatically activates the ENGINE and WING anti-ice system
How is bleed air directed for pneumatic anti-ice
Engines - independent
Wings - onside bleed
What compressor stage is bleed air tapped for anti-icing operations?
10th high stage valve (HSV)
What part of the engine is heated?
Engine Lip
What happens if there is a single bleed source failure?
The crossbleed automatically opens supplying airflow from one engine bleed to the opposite wing anti-ice
What happens to the engine bleed valve with the loss of electrical power?
The engine bleed valve is fail safe open
Do you have anti-ice protection during single engine?
- Only the running engine will have lip protection
- The wings will be heated
How should the MCDU be set if there are icing conditions present on the ground?
ALL
What does selecting ALL on the MCDU provide and how long does the protection last if no ice detected with the ice mode selector knob in AUTO?
Engine: ON when engines running; OFF at 1700’ or 5 min after liftoff whichever happens first
Wing: ON at 40 kts wheel speed; OFF at 1700 AGL or 5 mins after takeoff whichever happens first
When does the AUTO mode allow anti-ice to the engines and slats?
- Whenever icing is detected in flight
- Based on system logic according to A-I selecting on the MCDU T/O DATASET MENU page
What will happen on takeoff if the TO DATASET is set to ENG and the MODE selector is in AUTO and ice is detected?
The engine A/I will be on as long as the engines are running the wing A/I will be on up to 1,700’ or 2 mins after T/O
What will happen on takeoff if the TO DATASET is set to ENG and the MODE selector is in AUTO and ice is not detected?
The engine A/I will be on but the wing A/I will not
What does the pushed OUT position do on the selector knob for Engine 1 or 2 ice protection?
Closes the engine anti ice valve and prevents automation operation
If the wing or engine ice protection buttons are pushed out the associated ate-ice system is?
Deactivated
Turning the ICE PROTECTION MODE selector to ON does what?
Opens the engine and wing A/I valves
How would you configure the ENGINE and WING A/I system for automatic operation?
The ENGINE 1 (2) ICE PROTECTION pushbuttons must be in. OFF, ENG, or ALL must be selected on the MCDU TO DATASET menu
How do pilots know if icing conditions exist?
An ICE CONDITION advisory message on the EICAS
When is the windshield heated when the WINDSHIELD HEATING 1 or 2 button is pushed IN?
Always on when there is AC power available, except in specific conditions
What does the TIMER selection on the windshield wiper switch do?
Activates the associated wiper in 7 second intervals
When there is only 1 AC source how does it affect the windshield heating system?
On ground: load shed
In flight: Left side is heated, right heats if left is failed
What is the max airspeed for windshield wiper operations failed not in the park position?
320KIAS
What happens if the wiper is operated on a dry windshield?
- The wiper will stop
- To reset wiper move switch to OFF
When does the smart probes and TAT probe heat turn on?
When an engine is running
How many smart and TAT probes are there?
4 ADSP, 2 TAT
When do we use the ice protection test selector knob?
TEST function is a maintenance procedure
A failure of any of the water and waste heating systems is indicated?
On the flight attendant panel
What would cause an ENG REF A-I DISAG EICAS message?
Anytime the MCDU TO DATASET is in a different configuration from the aircraft bleed and A/I configuration
Name a few types of ice and which is most common?
Clear, mix, rime; Rime is most common
How should the aircraft be configured for de-icing?
Bleeds - OFF
Stab trim - Full nose down
Flaps - UP
Engines and APU ON or OFF
With the Ice Detection Mode Selector knob set to AUTO and the T/O DATASET “REF A/I” set to OFF, the wing and engine A/I is inhibited until when?
1700 AGL or 2 mins after liftoff, whichever occurs first
ASM 16-10
What speed could you use windshield wipers?
250 KIAS max
Are wings heated on the ground? At what speed do they heat?
Only if A/I is set to ALL - activates wheel speed >40 kts
ASM 16-10
How much of the wing is heated?
3 outboard leading edge slats
When are engines heated on the ground?
If the MCDU is set to ALL and the respective engine is running
With the ice detection mode selector set to ON, when will the engine A/I system operate?
When the engines are running
How do you recognize tailplane icing? What is the recommended recovery procedure when tailplane icing is felt?
- Lightness of yoke and usually occurs after changing configurations (flaps)
- Undo what you just did, use power judiciously, pull back on yoke
When must engine A/I be on?
All flight and ground ops when icing conditions exist or when ICE is annunciated, except in climb and cruise
When the ice detectors automatically activate the engine and wing A/I how long will the ice detectors remain activated?
For 5 mins after the detector is no longer sensing an icing condition
