Ice & Rain Control Systems Oral Flashcards
Why is it important that ice not be allowed to build up on airplane wings in flight?
Ice distorts the shape of the airfoil and destroys aerodynamic lift, weight of ice loads craft down.
Are pneumatic deicer boots operated before ice forms or after it has formed?
After, the boot inflates and breaks the ice and the air flowing over the wing blows it away.
Where does the air come from to operate the pneumatic deicer boots on a reciprocating-engine powered airplane?
Discharge side of the air pump used to operate gyro instruments.
What is meant by a wet vacuum pump?
A vacuum pump that uses engine oil to lubricate its steel vanes. (Dry vacuum pumps use carbon vanes)
What is the purpose of the oil separator in a deicer system?
Oil separators are used with wet vacuum pumps to remove oil from the discharge air before its used in the deicer boot.
How are rubber deicer boots cleaned?
By washing them w/ mild soap and water.
How does a thermal anti-icing system operate?
Hot compressor bleed air is ducted into a special chamber between a double skin in the leading edge of the wing. This hot air is controlled by a timer so ice is allowed to build up, and then the hot air breaks its bond to the skin. Air blows ice away.
What is used to remove frost from an aircraft before flight?
A mix of isopropyl alcohol and ethylene glycol.
How is ice prevented from forming on the windshield of modern jet transport
airplanes?
The windshield has a heater element embedded within, electricity heats the windshield and keeps ice from forming on it.
How is ice kept from forming on the pitot tube of an airplane?
Pitot tubes are heated by electricity flowing through elements built into them.
What are two ways rain can be kept from obstructing the pilot’s vision through the
windshield of an airplane?
The rain can be blown away by a high velocity blast of compressor bleed air, or it can be wiped away with electrically or hydraulically operated windshield wipers.
When should rain repellent be used on an airplane windshield?
Only when the windshield is wet with rain.
How is carburetor ice prevented in the engines of the smaller aircraft?
Heated air from the muff around the engine exhaust is directed into the carburetor.
How are rubber deicer boots attached to the leading edges of aircraft wings and tail
surfaces?
Some are attached w/ machine screw and rivnuts and others are bonded to the surface w/ an adhesive.
What keeps an electrically heated windshield from overheating?
Heat sensors built into the windshield control the current that is used to heat the windshield.
