AGK Systems - Aniti-Icing, De-Icing And Rain Protection Flashcards
Types of de/anti-icing.
Hot bleed air.
Hot engine oil.
Electrically heated mats.
Pneumatically operated mats.
Fluid.
What surfaces use pneumatic/bleed air de-icing?
leading edges, horizontal stabiliser leading edge, engine air intakes, gas path de-icer, sensors and probes.
What surfaces use electrical anti-icing?
Probes, windshields, propellers, horns
What does a vibrating rod do?
Detects ice.
Vibrates at constant 40Hz, when I ice builds up it slows down, heater automatically turned in and warning light displayed. Goes off when cleared.
What is a pressure operated head/ice detector?
Aneroid capsule connected to tube which protudes into the airflow.
Tube sensitive to air pressure due ti holes on leading edge.
Nomrally tube causes the capsule to expand.
If holes become blocked, tube pressure drops.
Aneroid capsule contracts, casuing electrical relay to close.
Probe is then heated.
What is a tedington rod?
Ice detector which senses the build up of ice. Then alerts the pilots.
What is an Ice formation spot light?
Crew can visually spot ice.
What is a pneumatic boot, de icing?
Rubber boots with inflatable tubes inside.
Expanded by compressed air.
breaks ice off between 0.5-1.5cm.
Fluid based ice protection.
Use isopropyl alcohol to de ice
Some anti icing protection.
Sequence is controlled by a timer.
Thermal ice protection systems.
Electrically powered mats or engine bleed air.
Jet transport aircraft use engine blee aur.
Turboprops use hot air from heat exchangers in exhaust or pneumatic boots.
Bleed air systems.
Air derived from aircraft pneumatic system.
De-Ice SOVs open to let air flow along stainless steel ducts.
Leading edge heated from inside to prevent ice formation.
Outermost slats not normally heated.
Sometimes swtiched off on take off or critical phases.
Bleed air uses isolation valve.
Engine anti ice.
2 systems:
one for engine
one for intake
The engine system is internal and may use hot engine oil and hot internal engine air.
Turboprop ice protection.
electrically heated mats.
Mats comprise of strips of resistive metal sandwiched between layers of fibreglass or neoprene.
Minimise electrical load mats switched on/off in sequence.
Propeller de icing system.
Ice forms near blade roots.
Electrically heated boots cover 50% of blade area.
Power supplied through slip rings and brushes.
Propeller fluid de icing.
Fluid is pumped into the singer ring,
Centrifugal force draws the fluid through the discharge pipe and out onto the blade.
