ice protection/detection

Question 1

what sources are used for aircraft anti-ice and de-icing?

Answer 1

bleed air heat
electric heat

Question 2

what uses bleed air (from the engine) for ice protection

Answer 2

engine LIPS
3 outboard slats (slat 2,3, and 4 on each wing)

Question 3

what uses electric heat for ice protection

Answer 3

smart probes
TAT probes
windshields
water lines
pressurization static port

Question 4

what does the ice protection system include?

Answer 4

wing anti-ice system
engine anti-ice system
windshield heating system
air data smart probes (ADSP/TAT) heating system
windshield wiper system

Question 5

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

Answer 5

yes the crossbleed valve opens to provide symmetrical ice protection for both wings
the failed engine does not receive heat to the engine lip

Question 6

how many ice detectors must be working to have ice detection?

Answer 6

one. there are two for redundancy

Question 7

how long will the de-icing system remain on after icing is no longer detected?

Answer 7

5 minutes

Question 8

if ICING on the MCDU is set to OFF and on takeoff roll, icing conditions are encountered, will the de=icing system turn on?

Answer 8

not until 1700 ft. or 2 minutes after takeofff, whichever happens first

Question 9

can the APU be used to provide bleed air for anti-icing

Answer 9

no

Question 10

what is protected from ice and rain?

Answer 10

engine inlets
wing leading edge
smart probes and total air temperature probes
windshields
water and waste drain systems

Question 11

is the ice protection system automatic?

Answer 11

yes, under normal conditionsc

Question 12

can the pilot over ride the automatic system?

Answer 12

yes

Question 13

how is ice detected in flight?

Answer 13

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 14

what compressor stage is bleed air tapped for anti-icing operations

Answer 14

10th high stage valve (HSV)

Question 15

how is bleed air directed for pneumatic anti-ice?

Answer 15

engines independent
wings onside bleed

Question 16

what happens if there is a single bleed source failure?

Answer 16

the crossbleed automatically opens

Question 17

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

Answer 17

ALL

Question 18

what does selected ALL on the MCDU provide?

Answer 18

Engine Anti-Ice
ON when engiens are running
wing anti ice - ON at 4 kts wheel speed

Question 19

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

Answer 19

1700’ AGL or 2 minutes after takeoff (whichever happens first)

Question 20

if OFF is selected on the ground, at what point will the anti-ice system become automatic?

Answer 20

1700’ AGL or 2 minutes after takeoff (whichever happens first)

Question 21

how does the failure of one of the two power sources affect the windshield heating system?

Answer 21

on ground inhibited
in flight - left side is heated (right heats if left has failed)

Question 22

what does the TIMER selection on the windshield wiper switch do?

Answer 22

activates the associated wiper in 8 second intervals

Question 23

what happens if teh wiper is operated on a dry windshield?

Answer 23

the wiper will stop
to reset wiper, move switch to OFF

Question 24

when do the smart probes heat?

Answer 24

when an engine is running

Question 25

is there a test for the anti-ice system?

Answer 25

YES but maintenance performs it

Question 26

how should the aircraft be configured for de-icing?

Answer 26

bleeds OFF
packs OFF
stab trim - full nose down
FLAPS UP
engines and APU ON OR OFF

Question 27

what temperature do we takeoff with Anti-ice on ENG

Answer 27

5-10 degrees celsius

Question 28

what temperature do we takeoff with anti-ice on ALL

Answer 28

less than 5 degrees C

Question 29

when does the wing anti-ice system test itself? how long does it take?

Answer 29

10 min after takeoff or at 10,000’ AGL (whichever occurs first)
60 seconds max