Ice & Rain Protection Flashcards
What does the ED display if there is ice?
ICE DETECTED
Heated ice protection components?
2 AoA vanes
2 Pitot/static probes
Leading edge of prop blades
Intakes on both engine
Pilot and copilot windshield
Pilot side window
Pilots standby static probe heated using DC power from the ess bus
Where are the ice detection probes located and how do they work?
Left and right side of the aircraft nose.
They vibrate at a frequency and any ice accumulation causes the vibration to increase due to increased rigidity.
How is the ice detection system activated?
Automatically when 115V AC power is available
REF SPEEDS switch to INCR does what?
White INCR REF SPEED message on ED
The stall protection system adjusts the stalk margin for operating in icing conditions
ICE DETECTED message on ED will flash yellow when?
When ice is detected but the REF SPEED switch is not set to INCR and it off
Are the ice detection probes heated?
Yes auto activated as soon as half a millimetre is detected, then rapidly heated till the ice melts, the heating element turns off allowing further ice build up and the cycle continues if still accumulating ice
Failure of both ice detection probes? What caution light?
Caution light ICE DETECT FAIL
How many sets of de icing boots?
6 sets
Wing leading edge inner and outer
Horizontal stab
Vertical stab
Inlet lips if the engine nacelles
De ice pressure tolerance?
18psi +/- 3
Airframe mode select switch settings?
Off
Slow
Fast
Manual
What do the Dual Distribution Valves do?
When open inflate the boots and when not inflated use suction to hold the boots flush with the leading edge
What controls the time of the boots?
Timer and monitor unit (TMU)
BOOT AIR switch does what?
ISO: isolation shutoff valve closed, isolating the left and right side of the airframe in case of a leak
NORM: isolation shutoff valve open, ensures adequate de ice pressure to both airframe sides if you are OEI
How to find a boot leak?
Set BOOT AIR switch to ISO and manually cyclic through the boots watching the de ice pressure gauge
If there is a leak in the vertical or horizontal stab can that be isolated with the ISO switch?
Not completely. There is a restrictor so loss of system pressure is restricted
Slow boot setting times?
3 min total cycle
6 sets for 6 seconds = 36 seconds
Dwell time 2min 24sec
Fast boot setting time?
1 min total cycle time
6 sets for 6 secs = 36 sec
Dwell time 24secs
Boot inflation lights do what?
Indicate adequate boot pressure of 15.5 psi is inflating the boot
Manual select switch used when?
If TMU fails or a system leak
Airframe manual limitations when pilot is doing it?
Don’t inflate any boot for longer than 6 seconds
Wait 24 seconds for swell time before starting another cycle
Why is it important to turn the airframe manual switch anti clockwise?
Incase there is a boot leak or failure then it prevents a major lateral imbalance if ice sheds from only one side as you cycle through
DEICE PRESS caution light indicates?
Loss of pressure in the deice system
How to confirm a boot leak?
Select ISO and use the manual airframe selector and cycle through looking at the de ice pressure gauge
DEICE TIMER caution light?
TMU failure. De ice system is operable using the manual mode