Winter Flying: A Strategic Approach

Winter presents many complications for those who live in northern latitudes. Residents of warmer states like Florida and Arizona probably consider us northerners to be their somewhat slow-witted (and perhaps crazy) cousins, but winter offers its own set of pleasures---and challenges.

Northerners, particularly northern aviators, must develop strategies to deal with winter's challenges. Some recreational pilots simply don't fly much, if at all, during the winter months. That's not my favorite strategy, since some of the smoothest air occurs in winter, and some really fun flying can be had.

Winter flying differs from summer flying in more ways than the need for long underwear during preflight inspections. Whereas summer flying is more of a tactical exercise, winter weather necessitates a more strategic approach.

From Wikipedia: "A strategy is a long-term plan of action designed to achieve a particular goal, most often ’winning.' Strategy is differentiated from tactics or immediate actions with resources at hand by its nature of being extensively premeditated, and often practically rehearsed."

In summer, many pilots look at the weather on a given morning or evening, and decide to go for a short flight, perhaps to a nearby pancake breakfast or maybe just for the joy of flight-seeing around the neighborhood. It's always advisable to get a thorough weather briefing prior to any flight, of course (which also provides pertinent information on NOTAMs and TFRs), but other than that, the drive to the airport and a preflight inspection are about all that are required to prepare for a summer flight. Oh, yeah---don't forget the sunglasses.

Winter demands a bit more preparation, hence my suggestion that winter flying is best thought of as a strategic effort, one that requires more advanced planning and preparation.

First things first: If your airplane resides outdoors or in an unheated hangar, you'll have to preheat the aircraft's engine prior to flight. You need to have a plan for safely accomplishing this and the time to do so adequately. If you have access to electricity where you park, an engine-mounted preheater may be your best choice. Unless you choose to leave these units energized all winter (and there are varying thoughts on this practice), use of these devices will require that you go to the airport well before the flight to plug in the heater. There are now units that use a cell phone to energize an engine heater with a phone call, but you still have to do so well in advance of your proposed departure.

If you use a combustion-type preheater prior to flight, you'll have to arrive at the airport early enough to accomplish a thorough preheat. That also means staying with the airplane as the engine preheats, because these things can burn if left unattended. And it's cold out there.

If the airplane is parked outside, you'll need wing covers to prevent frost, ice or snow buildup on the flying surfaces. They require additional time prior to flight to remove and stow. Speaking of thinking strategically, it's a good idea to order those covers before the first blast of wintry weather descends upon your part of the country.

Of course, the ideal solution is to park your airplane in a heated hangar. I've never been blessed with the use of a heated hangar for my personal airplane, but based on my experience as a working pilot in Alaska, a heated hangar can shorten your flying day by nearly two hours, compared to parking outdoors.

In summer, the weather feature that absorbs a great deal of our attention is the thunderstorm. There's no doubt that thunderstorms, particularly lines of thunderstorms, are a serious threat, but avoidance is the key to safety, and that's more of a tactical exercise than a strategic one. On the other hand, in the kinds of airplanes I often fly, trips around thunderstorms can become a long-term venture.

Winter weather, on the other hand, requires more of a strategic approach, particularly in terms of managing risk. The weather systems tend to be larger and there are some nasty conditions out there, such as icing, that are less of an issue in the summer. Also, winter weather tends to be more difficult to accurately forecast.

In winter, I try to update myself on the weather and weather patterns in my area (and approaching my area) on a daily basis, even if I don't plan to fly that day or if my flights will be local in nature. Having a feel for how fast frontal boundaries and low-pressure centers are moving can be invaluable in assessing winter flying risks. And winter flying is all about assessing and managing risk. I not only follow these weather features as they move across the country (including a review of the pertinent forecasts), but also try to guess the accuracy of the forecasts. A check of the current weather conditions at reporting stations along the pertinent weather feature will give a pretty good picture of how accurate the National Weather Service (NWS) forecast was for that time period and that area, and also how good my own "forecast" was.

Winter cross-country flights demand even more advanced preparation, and this is where the strategic nature of winter flying is most important. In winter, frontal systems and air masses are often larger and more difficult to predict than summer weather features. Frontal boundaries can stall, and low-pressure centers can intensify or move in a different direction than predicted. The keys to safe winter cross-country flying are educating yourself in aviation meteorology so you can make good assessments of potential weather conditions and looking ahead to try to determine what's coming your way or what you may fly into.

In preparation for a winter cross-country flight, it pays to start looking at the "big picture" weather about three days in advance. Checking weather patterns more than three days in advance of a flight isn't pointless, but weather patterns change so much and so rapidly that it's difficult to forecast more than a few days in advance with much reliability. A great start is with the 1800wxbrief.com, where you can get excellent aviation-specific weather products from common to cutting edge.  

There are many other web sites that offer excellent, free weather, including weather.gov. Publicly run sites also offer great options. Another public Website that I frequently use is the Weather Underground site at www.wunderground.com (for you children of the '60s---no, it's not subversive, but it does have some great graphics). Television weather broadcasts such as those on the Weather Channel are also helpful in getting a handle on big-picture weather---particularly trends.

More and more, the apps we use while flying, such as Garmin Pilot or ForeFlight, feature integrated weather and excellent planning utilities. I also like to peruse local public forecasts, which are often, if not always, prepared by a different meteorologist than the one who prepares the aviation forecasts. So, in effect, by looking at the local forecasts, you're seeking a second opinion. Public forecast weather isn't offered in aviation-specific parameters, so ceilings and visibility aren't available there. What's available is another forecaster's assessment of when a given weather feature may reach your proposed destination or route of flight, and that can be valuable information. The estimate of when rain or snow may begin should align pretty closely with the aviation forecaster's estimate of when ceilings and/or visibility will drop in the same area. If this isn't the case, it can suggest that the weather feature causing the change may be a difficult one to forecast. Aviator beware

Remember that forecasters, like pilots, are human. For more than 10 years, my office was next door to an NWS forecast office. I spent a lot of time with the meteorologists next door in an attempt to improve my own weather knowledge and, of course, to improve my dispatch reliability and safety. Every meteorologist I've met tries really hard to "get it right," but everyone has an off day. Forecasting weather is a difficult task, and while contemporary meteorologists have far more tools than their predecessors, the forecast itself is still one person's (and in some cases, one computer's) best guess about what will happen next. So, following the trends for a few days prior to a trip can help to identify an isolated questionable forecast.

As the day of the proposed launch approaches, a closer look at current weather created by the systems affecting the weather is justified. On the day of the proposed flight, my recommendation is to brief with an Automated Flight Service Station briefer. Why not simply self-brief? Many, if not most, aviators do just that. But because I want to get one more opinion on what the weather may be up to. Bear in mind that AFSS briefers are only permitted to provide the weather products to you---they aren't forecasters, but they can interpret the weather graphics over the phone and they can tell you how accurate the forecasts have been for a particular weather system. Briefers sit at a console and provide weather information to pilots during a full shift, day after day. Many of them become pretty good prognosticators in their own right, particularly if they work a certain region of the country all the time. While they aren't supposed to "interpret" the weather themselves, many of them will provide a pilot with a pretty good assessment of what they see in the observed weather, which can be invaluable. Unfortunately, we're losing some of this "tribal knowledge" in many areas because of the consolidation of the Flight Service function.

If, at the proposed launch time, the weather looks flyable---based on the capabilities of the aircraft and the pilot---a thorough preflight inspection is in order. While cold and dark may make winter preflights less pleasant, it's even more essential that the winter preflight be thorough. Fuel quantities and quality should be verified. Using an anti-icing additive in the aircraft's fuel in winter helps to prevent fuel-line blockages and stuck quick drains. Be sure to consult the engine manufacturer's recommendations on which additive to use, but for most piston-engine aircraft, either Prist or isopropyl alcohol is approved for use.

As you load your gear for the flight, double-check your survival gear, including sleeping bags for all occupants and other cold-weather gear. A personal locator beacon (PLB) is a great addition to your personal survival gear, particularly in winter, when a rescue can be accelerated greatly by one of these devices. Be sure the engine cover and wing covers are aboard. In winter, I bring a small combustion heater called a Northern Companion to use both as a survival stove and as an engine preheater in the event I have to land at an airport with limited services. Having the tools to bed down your airplane almost anywhere is an essential winter-flying strategy. Knowing that you'll be able to get the airplane going again in the morning, regardless of where you park for the night, opens all sorts of options when your best weather assessments just don't pan out and getting on the ground fast is your best option.

If you opt not to fly a planned trip, don't just forget about the trip; continue to watch the weather conditions along your proposed route of flight to see if your decision to stay on the ground was well founded. If it was, congratulate yourself for being a good strategic planner. If not, consider it a learning process, store the knowledge you gained on this one, and apply it to the next flight.

By all means, take advantage of the winter flying opportunities that are available. Join the skiers and snowmobile crowd. If you can't avoid winter, learn to enjoy it, and a strategic approach to your flying will help you do so safely.