Winter Flying in the Appalachians

By Ken Kostura

Winter weather can adversely affect flight operations. Poor weather conditions with rapid moving fronts, strong and gusty winds, winter precipitation, blowing and drifting of snow, and icing conditions are several of the hazards to winter flying. Winter flying requires pilots to use careful planning, and exercise good judgment in analyzing weather situations. Some local weather thoughts pertaining to the TAFs can be found under the aviation section of the Area Forecast Discussion.

Small Plane in Snow

A thorough preflight inspection is important in temperature extremes. Remember to wear appropriate gear and complete your best preflight inspection. Fuel contamination is a possibility in cold climates if your warm aircraft has been parked with half empty tanks in the cold. The condensation of water in your tanks is a possibility. Pilots should drain sufficient fuel to see if it is free of contaminants.

Aircraft preheating before startup is advised because low temperatures can change the viscosity of engine oil, batteries can lose a high percentage of their effectiveness, instruments can stick and warning lights can freeze in position. Another cold start problem that plagues an unheated engine is icing over the spark plug electrodes.
After the engine starts, use of carburetor heat may assist in fuel vaporization until the engine obtains sufficient heat. Radios should be turn on after the aircraft has a chance to warm up and then be tuned to the desired frequency.

The FAA recommends that all frost, snow, and ice be removed before attempting flight.
Pilots should not count the snow blowing off on the takeoff roll. Special attention should be given to openings in the aircraft where snow can enter, freeze solid, and obstruct operation. Some of the opening that should be free of snow and ice before flight are
pitot tubes, heater intakes, carburetor intakes, anti torque and elevator controls, main wheel and tail wheel wells, where snow can freeze around elevators and rudder controls.
Fuel tank vents should be checked to prevent engine stoppage.

Ice or snow on the runway or taxiway creates poor braking action. Short turns and quick stops in the aircraft should be avoided. Refreezing of water on runways could create black ice conditions.

Photo of plane crash and helicopter in snow

Pictures from the FAA aviation safety program.


Snow showers and whiteout conditions are two en route hazards that require shift to
IFR flight. The pilot should be prepared for these both from the standpoint of training and aircraft equipment.

Carburetor ice generally forms in temperatures between 32 and 80 degrees F, if humidity is 50% or more. If visible moisture is present, ice will form at temperatures between 15 and 32 degrees F. Winter flying also involves the use of cabin heaters; be watchful for the signs of carbon monoxide poisoning.

Icing is a major problem during the winter. Light icing over a prolonged period may become a serious problem. After receiving your official weather briefing, note the temperature and dewpoint for icing potential. Refer to the Icing chart from FAA.

Carburetor icing chart

serious icing legend

  Serious Icing - cruise or climb power

moderate icing legend

  Moderate Icing - Cruise power or serious icing – glide power

serious icing, glide power legend

  Serious Icing - glide power

light icing, glide or cruise power legend

  Light Icing - glide or cruise power

 

The Aviation Weather Center’s Aviation Digital Data Service (ADDS) page provides a good reference for aviators. Some of the winter time products include Current Icing Advisories, Pilot reports of Icing, Supplementary Icing information (CIP/FIP) and freezing level graphics.

It is important to have a life support kit ready in your plane in the event of an emergency.
The time to prepare for an emergency is before anything happens. This is a good time to pull out you airplanes operation manual and prepare for winter.