An important factor affecting the safe conduct of the flight will be the existence of icing conditions the aircraft may encounter. There are two distinct types of icing that are of interest to the pilot in command: structural icing of the aircraft, and the formation of ice in the carburetor of normally-aspirated piston-powered aircraft are of concern to all pilots.

 

Structural icing will only occur when visible moisture is present as clouds or rain and when temperatures are between zero degree Celsius (32–degrees Fahrenheit) and -10–degrees Celsius (14–degrees Fahrenheit).

 

Between these temperatures water droplets become super cooled, that is the temperature of the water is below freezing but the water remains in liquid form. As the aircraft passes though the super cooled water droplets, the disturbance of the passing structure causes those droplets that strike the aircraft to freeze and adhere to the wings, propellers, antennas, and external structures of the aircraft. Structural icing can also clog the air and oil cooler intakes of the aircraft, causing an engine stoppage.

 

Structural aircraft icing can become a serious concern for the pilot. Icing robs the wings of lift because of the change in the shape of the wing as the ice layer builds. Ice adhering to the propeller causes a loss of thrust. The buildup of ice also will cause an increase in the aircraft’s weight. All these factors will contribute to an increase in the aircraft’s stalling speed and the degradation of the handling characteristics of the aircraft, which can lead to a possible loss of control.

 

The buildup of ice on the aircraft’s external instrument masts, such as the pitot tube, may cause incorrect indications of airspeed and altitude. Ice on the radio masts will degrade the aircraft’s ability to communicate with ground stations and may lead to the loss of those masts, for they sometimes break off the aircraft due to slipstream pressure.

 

The best way to avoid icing if you are the pilot in command of an aircraft not equipped to operate in icing conditions is to do just that; avoid areas that are reported by ground stations or by pilot reports to contain icing conditions. If the pilot inadvertently encounters icing during the flight, he should immediately change altitude by climbing or descending to an altitude where icing will no longer be present. If necessary a 180–degree turn away from the area of icing will remove the aircraft from the icing encounter.

 

Some aircraft are equipped with devices that allow operations in known icing. Aircraft may be equipped with rubber boots on the leading edges of the wings. After the wing leading edge has accumulated one-half to 1-inch of ice the boots are inflated using the vacuum pump on the engine. The expanding boot will then crack the layer of ice and the leading edge of the wing will again be clear of ice. Another de-icing device is known as a weeping wing. The system is attached or built into the leading edge of the wing. As icing conditions are encountered, a solution of ethylene glycol seeps onto the wing’s leading edge, preventing ice from forming.

Turbine (jet) powered aircraft may have hot wings. The hot wing system of anti-icing is used to prevent ice from forming or adhering to the wing. A portion of the hot air produced by the turbine engine is pumped into a channel under the leading edge of the wing, which becomes to hot for ice to form or to adhere if already encountered.

 

Other systems, such as electrically heated pads and alcohol spraying systems, are used to prevent or remove ice from the propellers and windshields of the aircraft. Similar systems are used to protect the engine air intakes of turbine-powered aircraft.

 

Another type of icing that may be encountered during any time of year and in almost any temperature is induction system icing. In aircraft equipped with carburetors, the possibility of ice forming in the throat of the carburetor can cause loss of engine power. Carburetor– equipped aircraft have carburetor heat levers in the cockpit. The carburetor heat system, when activated, diverts some hot air that is generated by the engine’s exhaust pipes into the carburetor of the aircraft engine to melt any accumulation of ice. In some aircraft the use of carburetor heat is a required item in the pre-landing checklist.

 

Runway Open!                          

Resurfacing of the runway at Santa Ynez Airport has been completed. Operations returned to normal a day earlier than anticipated on Sept. 27. The first to use the newly resurfaced runway was pilot Alan Jones of Sunwest Aviation. Sunwest Aviation operates a twin-engine Cessna 310 and is the only air taxi company serving the Santa Ynez Valley out of the local airport.