Warm up for cold-weather flying

If you don’t have the luxury of operating an aircraft that’s housed in a heated hangar, the key to flying when temperatures fall to around 30 degrees Fahrenheit or lower is to allow extra time to preheat the engine; ensure all snow, ice, or frost is removed from the aircraft; check that carbon monoxide detectors are installed and working; pack a winter-specific survival kit; and dress for being in the elements during preflight or in the event an emergency off-airport landing requires egress.

Warm up the engine

Preheating the aircraft’s engine will save wear and tear and make start-up much smoother. According to engine manufacturer Lycoming, “In extremely low temperatures, oil congeals, battery capacity is lowered, and the starter can be overworked. Improper cold weather starting can result in abnormal engine wear, reduced performance, shortened time between overhauls, or failure for the engine to operate properly.”

Preheating an engine is easiest when you have the option to move the airplane into a heated hangar, ideally the night before your flight, but a minimum of four hours before flying. If the FBO is busy, or heated hangar space is limited, it's best to arrange for this in advance.

For those without such luxury, there are many products available designed to safely heat aircraft engines, including pre-installed electric heaters that plug into a power outlet or a small generator. FBOs typically have hot air combustion heaters to preheat the aircraft. In more remote areas, pilots may use liquid-fueled portable heaters that require (significantly) more caution because they produce open flame. Engine and propeller blankets trap warm air and speed the preheating process for any heater.

Check your aircraft’s pilot’s operating handbook to see if it lists a target temperature for preheating. If you rent an aircraft, the FBO or flight school also might have limits or specific procedures in place. (While you are digging into the POH, look for the recommended winter weight oil to ensure the right viscosity is being used.)

If you have access to electricity, consider also using a small preheater in the cockpit to warm up the instrument panel during periods of extreme cold. This should be done only while you are with the aircraft.

Check for frost, snow, ice

For aircraft tied down on the ramp, check for the presence of frost, snow, and ice. All aircraft surfaces must be free of these contaminants. According to this NTSB safety alert, “Fine particles of frost or ice, the size of a grain of table salt and distributed as sparsely as one per square centimeter over an airplane wing’s upper surface, can destroy enough lift to prevent a plane from taking off.

“Virtually imperceptible amounts of ice on an aircraft wing’s upper surface during takeoff can result in significant performance degradation.”

Be aware if you fly an aircraft kept in a heated hangar and then go for an early flight for coffee and hotcakes: Frost can form on the surfaces while it is tied down outside during your leisurely breakfast. Inspect the aircraft, particularly the upper surfaces of the wing, to ensure it does not have any frost.

If an aircraft has frost, snow, or ice on it, move it into a heated hangar until the ice melts and all surfaces are completely free of any trace amounts of contaminants. If a heated hangar isn’t an option, reschedule the flight for another time—perhaps even later in the day if the temperatures are expected to rise and the sun will be shining on the aircraft.

In addition to checking the surfaces for contaminants, you should also check items like hoses, cables, static wicks, brakes, and wheel wells. The FAA provides a detailed list of the items to check when flying in cold weather, along with helpful explanations.

Prevent carbon monoxide poisoning

Inspect your aircraft’s cabin heater shroud and system to ensure there are no cracks that would allow exhaust and carbon monoxide in the cabin. “Each year accident investigations have revealed that carbon monoxide has been a probable cause in accidents that have occurred in cold weather operations,” the FAA notes. While the gas itself is colorless and odorless, if you smell exhaust, carbon monoxide is likely present, and you should turn off the heater and open the air vents to let in fresh air.

Make sure carbon monoxide detectors are installed in the aircraft. Carbon monoxide detectors can range from peel-and-stick boards that change color when the gas is present to electronic detectors that provide visual and audible alerts when it is present.

Pack a winter survival kit

Whether you fly over remote or populated areas, you should pack a winter survival kit to have in the airplane for each flight. After an emergency off-airport landing, you will need items to help keep yourself warm, dry, hydrated, and nourished until help arrives, as well as tools to help you signal for help. Strong winds with temperatures as low as 20 degrees Fahrenheit can cause frostbite in as few as 20 minutes.

If you will be flying over populated areas or terrain that is easily accessible by land, include a sleeping bag rated at and below the temperatures in which you will be flying, a tarp with a shiny side (that can be used to hold in heat or signal rescuers), water, snacks such as protein bars, and fire-starting equipment. For flying over remote, difficult-to-access areas, you’ll want to pack a winter survival kit that could help you survive the elements for a few days. For more information about what to pack in a survival kit, read the AOPA Pilot article, “Survival Mode,” as well as the survival section of the FAA’s winter flying tips.

Dress to egress

Preflight inspections on a cold, windy ramp can be painful if you aren’t dressed appropriately. Consider an insulated wind-breaking jacket, ski pants, a warm hat, gloves that will still allow you to move your fingers freely and remain comfortable while you inspect the airplane, and warm boots. Winter clothing will keep you protected while you methodically inspect the airplane with the additional cold-weather items included. If the airplane you will be flying has a 180-horsepower or greater engine, then you’ll likely have a decent heater and not need all that gear while you are flying. Just change out of the warm gear and pack it in a bag to have in the airplane. This way, you will only be exposed to the cold during the walk from the FBO or flight school to the airplane and you’ll have emergency gear in the aircraft if needed. If you will be flying a lower-horsepower aircraft with a weaker heater, you might want to leave most of that gear on.

With these precautions in place, you and the aircraft will be ready to fly safely during colder weather to experience the beauty of snow from above, clear skies with unlimited visibility, and superior aircraft performance.