What is a slinger ring?
It is a device on the hub of a propeller that slings deice fluid onto the propeller when it's spinning.
What four main items on a large transport aircraft would be protected by anti icing systems?
Wing leading edges
Empennage leading edges
Engine nacelle leading edges
Windshields
What are the negative effects of ice on an airframe?
Adds weight
Disrupts airflow over airfoils
Creates drag
Is there another advantage, besides ice protection, to heating up windshields?
Yes, the heat makes them less brittle.
why is it a bad idea to open alternate air source on the ground?
Because the system can ingest debris from the ground.
Name one ice/rain prevention for windshields on small private aircraft.
Heated panel over a small area of the windshield.
Ducted warm air directed onto the inside of the windshield.
What are the preflight de icing steps for a large transport aircraft and which step performs what action?
A thin, heated fluid is sprayed on the relevant surfaces, which removes and snow or ice that has accumulated; then a thick fluid is sprayed, which sticks to the surfaces and keeps new ice from forming.
What are the negative effects of ice on engines? Both turbine and reciprocating.
Turbine: ice can enter the compressor area and damage the blades.
Turbine: ice can disrupt airflow.
Turbine: ice can clog up sensors and give erroneous readings.
Recip: ice can clog the carburetor, either stopping fuel flow or blocking air flow
Propellers: ice can cause imbalance, vibrations, loss of thrust and can throw pieces of ice onto the airframe.
How is a large transport aircraft windshield constructed?
Layers of tempered glass with vinyl and conductive layers sandwiched in between.
How does alcohol remove and prevent ice?
It it has a lower freezing point than water.
What is the purpose of looking at the air pressure gauge on a system with pneumatic de ice boots?
If the gauge is fluctuating, that is an indication that the boots are inflating and deflating.
What are two main ways ice is prevented on turbine spinners?
A rubber tip that sheds ice before much can form.
A heated cone.
Name the three types of ice and describe each.
Glaze Ice - thick, clear ice
Rime Ice - Fuzzy, lightweight ice
Frost - flat, opaque ice, that is very thin.
It indicates that the heat is working.
Alcohol spray into the carb throat.
Warm air - can come from an independent combustion heater, from an exhaust shroud, or from augmentor tubes downstream from the exhaust.
Name two disadvantages of the weeping wing system.
Heavy,
Requires a lot of maintenance.
Time is limited by the size of the reservoir.
On large transport aircraft where is bleed air used for ice protection?
Anti icing leading edges of wings and empennage, and engine inlet cowls.
Where does the air come from to power pneumatic boots on a reciprocating aircraft. What about turbine aircraft?
On a reciprocating aircraft, it will come from an air pump; on a turbine aircraft it will come from bleed air.
Give at least two examples where electricity is used to prevent or remove ice.
Deice boots on propeller
Electric deice boots on leading edges
Probe heat
Windshield heat
Do engines with fuel injection need carb heat? What system do they need instead?
They do not need carb heat since they don't have carburetors. They do have air inlet filters, which can clog with ice, so they need an alternate air source for the engines.
What are augmentor tubes used for?
They are used to increase airflow from the exhaust of a medium to large reciprocating engine. This flow is then routed to the carburetor for de icing purposes.
How did ice effect the engines of the aircraft in the Mayday episode we watched this week?
It clogged the engine pressure ratio sensor and gave false readings.
It is water that has reached a temperature below freezing, but hasn't turned into ice. As soon as it contacts a surface, it will immediately turn to ice.
How are slip rings and brushes relevant to de icing?
it's how electricity transmitted to the propeller on a system that has electric propeller deicing.
Should you keep carb heat on for the duration of a flight? why or why not?
No, carb heat will cause the fuel/air mixture to become too rich (meaning too much fuel for the air) and this will effect engine performance.