Ice Protection/Detection Flashcards
What uses bleed air for ice protection?
Engine lips
3 outboard slats
What sources are used for aircraft anti-icing and deicing?
Bleed air heat
Electric heat
What uses electric heat for ice protection?
Pitot-static system Windshields Water drain masts Pressurization static port Water/Waste service ports TAT probes
If an engine fails, does the opposite wing and engine receive ice protection?
Yes. The crossbreed valve opens to provide symmetrical ice protection for both wings
The failed engine does not receive heat to the engine lip
How many ice detectors you must be working to have icing detection?
One. There are two for redundancy
How long will the deicing system remain on after icing is no longer detected?
2 minutes after icing stops being detected
Can the APU be used to provide bleed air for deicing?
No
What is protected from ice and rain?
Engine inlets Wing leading-edge Smart probes Windshields Water & Waste drain systems
Is the ice protection system automatic?
Yes, under normal conditions
Can the pilot over at the automatic system?
Yes
How is ice detected in flight?
2 ice detectors
Vibrating sensor element that changes frequency when ice builds up around it.
Once ice is detected, the sensor element heats, the ice melts, the normal vibrating characteristics are restored, and the heating process stops. The cycle repeats as ice rebuilds on the probes.
What compressor stage is bleed air trapped for anti-icing operations?
10th High Stage Valve (HSV)
How was bleed air directed for pneumatic anti-ice?
Engines- independent
Wings- onside bleed
What happens if there is a single believe the source of failure?
The cross bleed automatically opens.
How should the MCDU be set if there are icing conditions present on the ground?
‘ALL’
What does the ‘ALL’ on the MCDU provide?
Engine anti-ice- ON when engines are running
Wing anti-ice- ON at 40 kts wheel speed
If ‘ALL’ is selected on the ground, at what point will the anti-ice system become automatic?
1700’ AGL or two minutes after takeoff (whichever happens first)
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?
The wiper will stop
To reset wiper, move switch to ‘OFF’
When do the smart probes heat?
When an engine is running.
Is there a test for the anti-ice system?
Yes, but maintenance performs this test. Also a self test which occurs at 10,000’ or 10 minutes after take off.
How should the aircraft be configured for deicing?
- Bleeds OFF
- Stab trim Full nose down
- Flaps UP
- Engines and APU ON or OFF
