Ice Protection Flashcards
T/F: De-icing systems are used to get rid of ice that has already formed.
TRUE
T/F: De-icing systems are used to prevent ice from forming.
FALSE, de-ice remove ice that has already formed
T/F: Anti-icing systems are used to prevent ice from forming.
TRUE
T/F: Anti-icing systems are used to get rid of ice that has already formed.
FALSE, anti-ice systems prevent ice from forming, not remove it after it is formed
How many electronic ice detection probes are installed on the aircraft?
2 (either side of the lower forward fuselage)
Where are the electronic ice detection probes located on the aircraft?
Either side of the lower forward fuselage
How much ice needs to be detected before an indication is displayed on the ED?
0.5mm
T/F: When the ice detection probes detect ice, they heat to melt the ice off.
TRUE, allows it to detect ice again
When will the ICE DETECT FAIL caution light illuminate?
If both probes fail
T/F: If one ice detection probe is working, no alert is provided.
TRUE, both probes must fail for an alert
What inflates the de-icing boots?
Bleed air from the engines
Which aircraft structures do not have deicing boots that use bleed air?
(Answer which ones DO have deicing boots)
Leading edges of wings
Horizontal stabilizer
Vertical stabilizer
Engine nacelle inlet
T/F: Boot inflation for all the de-ice boots is regulated by a single distributor valve.
FALSE, they are Dual Distributing Valves (DDV)
In order for the TMU to send signals automatically, the airframe mode select switch must not be selected to which position?
Manual
TMU = Timer Monitor Unit
How long does each de-ice boot inflate?
6 seconds (SLOW/FAST only changes dwell time between inflations, not the time of actual boot inflation)
T/F: If a malfunction occurs in the automatic timer, the boots can be inflated manually.
TRUE
When should pilots move to the next boot position when using the deicing boots in manual mode?
Wait until the lights illuminate to show full inflation of each position, then rotate to next position
T/F: The DDV’s and check valves have integral heaters which are automatically activated.
TRUE
What is the normal position for the airframe mode select switch?
MANUAL
T/F: If the TMU temperature monitoring detector fails, the valve heaters default to a permanent ON position to ensure they remain heated.
TRUE
When a pneumatic line ruptures on either side of the aircraft, the de-ice system should be set to _____.
ISO
T/F: All the boots on the horizontal and vertical stabilizers are pneumatically cross-connected.
TRUE
ensures de-ice to tail
When will the DEICE PRESS caution light illuminate?
Less than 15psi available to either side
Less than 15psi supplied after DDV opens
Greater than 15psi after DDV closes
What heats the propeller blades?
115VAC electrically heats elements on blades
T/F: The heater cycle for each propeller is controlled by a timer monitor control unit.
TRUE
T/F: The TMCU adjusts prop heat cycle times depending on the total air moisture.
FALSE, it adjusts depending on Total Air Temperature (TAT)
The Total Air Temperature (TAT) must be equal to or lower than _____ for the propeller heaters to operate.
5C
T/F: The propellers alternate being heated to reduce electrical load.
TRUE
T/F: Both propellers are heated at the same time.
FALSE, propellers are heated alternately to reduce electrical load
What do the prop indicator lights on the Ice Protection panel indicate when illuminated?
The related propeller is being heated to all blade elements
The TMCU can only begin a propeller heating cycle if Np is above _____.
400 RPM
Np is speed of propeller in RPM
Which statement is true regarding prop heat duration as it related to temperature?
The colder the temperature the longer the ON time and the longer the OFF time
Once pilots have performed a propeller heat test, how long must they wait until the next propeller test can be performed?
30 seconds
When is the engine intake heat energized?
When intake bypass doors are opened AND
Engine is running (oil pressure) AND
SAT is below 15 C AND
115VAC power is available
What air temperature causes the engine heater to energize?
15 C or below
How are the static ports heated?
Integral heaters using electric power #1 pitot/static = 115VAC by left AC bus #2 pitot/static = 115VAC by right AC bus Standby pilot/static = 28VDC from right DC essential bus
How are the pitot tubes heated?
Integral heaters using electric power #1 pitot/static = 115VAC by left AC bus #2 pitot/static = 115VAC by right AC bus Standby pilot/static = 28VDC from right DC essential bus
How many volts are needed to power the #1 and #2 probe heaters?
115VAC
When set to NORM, the windshield is being heated at _____.
Full power (WARM UP = 1/2 power)
How many wiper blades are installed on the aircraft?
2, one for each forward windshield
Anti-ice equipment is primarily powered by what source?
115VAC power
T/F: Boot inflation time is the same in both fast and slow modes.
TRUE, 6 seconds
T/F: All propeller blades on both engines are heated at the same time.
FALSE, one propeller is heated at a time to reduce electrical load
Which of the following statements best described AOA vane heat?
It is completely automatic with no flightdeck controls
115VAC power must be available
No caution light to indicate heater failure, however, PUSHER SYS FAIL and STALL SYS FAIL will indicate if AOA heater element fails
Which window in the flight deck is not heated?
Right side co-pilot window
