Ice Protection/Detection

Question 0

What uses bleed air for ice protection?

Answer 0

Engine lips

3 outboard slats

Question 1

What sources are used for aircraft anti-icing and deicing?

Answer 1

Bleed air heat

Electric heat

Question 2

What uses electric heat for ice protection?

Answer 2

Pitot-static system
Windshields
Water drain masts
Pressurization static port
Water/Waste service ports
TAT probes

Question 3

If an engine fails, does the opposite wing and engine receive ice protection?

Answer 3

Yes. The crossbreed valve opens to provide symmetrical ice protection for both wings
The failed engine does not receive heat to the engine lip

Question 4

How many ice detectors you must be working to have icing detection?

Answer 4

One. There are two for redundancy

Question 5

How long will the deicing system remain on after icing is no longer detected?

Answer 5

2 minutes after icing stops being detected

Question 6

Can the APU be used to provide bleed air for deicing?

Answer 6

No

Question 7

What is protected from ice and rain?

Answer 7

Engine inlets
Wing leading-edge
Smart probes
Windshields
Water & Waste drain systems

Question 8

Is the ice protection system automatic?

Answer 8

Yes, under normal conditions

Question 9

Can the pilot over at the automatic system?

Answer 9

Yes

Question 10

How is ice detected in flight?

Answer 10

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.

Question 11

What compressor stage is bleed air trapped for anti-icing operations?

Answer 11

10th High Stage Valve (HSV)

Question 12

How was bleed air directed for pneumatic anti-ice?

Answer 12

Engines- independent

Wings- onside bleed

Question 13

What happens if there is a single believe the source of failure?

Answer 13

The cross bleed automatically opens.

Question 14

How should the MCDU be set if there are icing conditions present on the ground?

Answer 14

‘ALL’

Question 15

What does the ‘ALL’ on the MCDU provide?

Answer 15

Engine anti-ice- ON when engines are running

Wing anti-ice- ON at 40 kts wheel speed

Question 16

If ‘ALL’ is selected on the ground, at what point will the anti-ice system become automatic?

Answer 16

1700’ AGL or two minutes after takeoff (whichever happens first)

Question 17

What does the ‘TIMER’ selection on the windshield wiper switch do?

Answer 17

Activates the associated wiper in 8 second intervals

Question 18

What happens if the wiper is operated on a dry windshield?

Answer 18

The wiper will stop

To reset wiper, move switch to ‘OFF’

Question 19

When do the smart probes heat?

Answer 19

When an engine is running.

Question 20

Is there a test for the anti-ice system?

Answer 20

Yes, but maintenance performs this test. Also a self test which occurs at 10,000’ or 10 minutes after take off.

Question 21

How should the aircraft be configured for deicing?

Answer 21

• Bleeds OFF
• Stab trim Full nose down
• Flaps UP
• Engines and APU ON or OFF