Aircraft Deicing System Parts for Safe Operation in Icy Conditions

Deicing systems ensure that aircraft aerodynamics can be maintained when ice has formed on the surface of an aircraft. Aircraft Deicing Equipment is different from anti-icing equipment in that they are designed to remove ice from the surface of an aircraft once it has formed; anti-icing equipment is used to prevent the formation of ice. There are three main deicing and anti-ice systems utilized in the aerospace industry: deicing boots, chemical, and thermal deice and anti-ice systems.

Aircraft size and powerplant system determine what deicing system — or combination of systems — will be utilized in icing conditions. Though equipment types differ in functionality, they are all used to protect leading edges of various aircraft components: wing and tail surfaces, horizontal stabilizer, fuel tank vents, pitot and static port openings, propeller blades, stall warning equipment, vertical stabilizer, windshields and others.

Prominent manufacturers of deice and anti-ice systems and relative components include B/E Aerospace, Eaton, GKN Aerospace, Goodrich, and Hartzell Propeller.

Deicing Boots

This equipment is utilized to prevent ice buildup on the leading edges of an aircraft. Deicing boots are rubber inflatable panels, or tubes, that are installed on the leading edge of an airfoil; when inflated, the boots are designed to crack the ice off of the aircraft. They are powered by engine-driven pneumatic pumps, which can be controlled manually by the pilot or automatically via flight deck avionics. Common parts integrated in a deicing boot system include the following: annunciator light, check valves, edge sealers, flow control valves, metal rollers, pneumatic pressure gauge, rubber rollers, and others.

Chemical Deicing and Anti-icing

This deicing and anti-icing method is used for propellers, windscreens, leading edges, and entire airframes. Glycol based fluid (TKS fluid) and alcohol are the most commonly used chemicals in these systems. In a method of deicing known as weeping wings, small perforations installed in the leading of the wing discharge an antifreeze solution to break down ice that has formed on the aircraft. This system can also act as an anti-ice system when activated before an aircraft encounters icing conditions. Adapters, couplings, fluid injectors, mesh screens, and variable rate nozzles are all components that are commonly utilized in these systems.

Propeller Chemical Anti-icing

Chemical anti-ice equipment for propellers also integrates alcohol-based fluid. Discharge nozzles installed in the propeller system distribute alcohol onto each blade, and centrifugal force disperses fluid out to the leading edges. Propeller anti-ice systems integrate the following components: brush assembly, shim, slip rings, and others.

Windshield Chemical Anti-icing

Alcohol is a common chemical used in windscreen anti-ice systems. Devices integrated in this system emit a flow of alcohol to the windscreen to prevent ice formation on its surface. The pilot can monitor and adjust the alcohol flow through the flight deck controls.

Thermal Anti-ice Systems

While they are a preventative anti-ice system, thermal anti-ice systems are commonly used in combination with deicing systems. There are two main types of thermal anti-ice systems: bleed air and electro-thermal. The functionality of a bleed air system directs hot air from an engine compressor unit to leading edge surfaces to prevent ice formation on the aircraft. Electro-thermal systems utilize electrical wiring harnesses to heat aircraft surfaces. Thermal systems are the most common de-ice and anti-ice method used for commercial aircraft and airliners. These systems typically integrate the following components:  digital icing sensors, ducting, graphite heaters, heater mats, pitot tubes, power converter units, wire harnesses, thermal conductive fiber, and others.

Propeller Anti-ice Heating System

Propeller anti-ice heating systems combine deicing boots and thermal anti-ice technologies. Inflatable boots installed on inboard and outboard segments of a propeller blade are integrated with an electrical wire system. The embedded wires use electrical current to heat the boot structure and act as an anti-ice method for the propeller blade. Standard components of this system include brush blocks, slip rings, and wire harnesses.

Windshield Thermal Anti-ice System

In this system, conductive material embedded within the windshield transmits electrical current across its surface. Windshield thermal anti-ice systems are activated during flight and are typically controlled by the pilot or flight deck.