Airframe Ice + Rain Control Flashcards
What controls the temperature in a thermal anti-icing system?
Hot and cold air are mixed.
What are the sources of heat for thermal anti-icing systems?
Bleed air from the compressor.
Engine exhaust heat exchangers.
Combustion heaters.
What prevents overheating of the leading edges of a thermal anti-ice system operated by engine bleed air?
Overheat sensors signal the anti-icing valves to close and shut off the hot air.
What happens to the hot air used by a thermal anti-ice system after it has heated the surface?
The air is dumped overboard.
Why is it necessary to provide overheat protection for an anti-icing system that uses turbine engine bleed air?
The air is hot enough to cause damage to the aircraft structure.
What are the effects of arcing on an electrically heated windshield?
Localized overheating. Damage to the windshield.
Can the operation of an electrically heated pitot tube be checked with the aircraft’s ammeter, and if so, how?
Yes.
Turn the Pitot heater on, and observe the deflection of the ammeter needle.
Describe several potential problems associated with electrically heated windshield:
Arcing.
Delamination.
Scratches.
Discoloration.
Why do some pneumatic deicer boot systems have an electrically operated timer?
To automatically cycle the boots.
Provide the proper rest time.
Then recycle the boots.
What are the two common methods of inflating pneumatic deicer boots?
Bleed air from a turbine engine.
Exhaust from an engine driven vacuum pump.
What procedure is used to hold deicer boots flat with an airfoil surface during flight?
Suction is applied to the boots.
Why do some deicer boot systems incorporate an oil separator?
If a wet pump system is used, the oil must be removed before it reaches the boot because oil damages the rubber.
What methods are used to attach a deicer boot to the leading edges of the wing and tail surfaces?
Adhesives.
Ferring strips and screws.
A combination of both.
What important steps should be taken prior to making a cold patch repair to a deicer boot?
Consult the manufacturer’s service manual and follow the repair instructions explicitly.
Describe the methods commonly used to remove rain from a windshield:
Windshield wipers.
A blast of air.
Chemical rain repellent.