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VINTAGE INSTRUCTOR

THE

DOUG STEWART

Winter Operations I was planning on leaving for the airport early this morning to meet a client for tailwheel training in my 1947 Piper Super Cruiser. The thermometer outside my window was registering in the mid-30s (and this was just the first week of November), and the wind was making a moaning sound as it blew the last of the dying maple leaves around the corners of my house. Looking up at the dark gray clouds whipping past overhead, I noticed that there were snowflakes here and there. How could this be? Just a few weeks ago I was still wearing shorts and a T-shirt, and now I had to think about winter operations. It seemed like only yesterday that I was concerned about density altitude considerations, and watching oil and cylinder head temperatures on the climb out. Today I would have to think about the possibility of an engine preheat, and my own body would need the extra warmth of a pair of long johns for the cold back seat of my PA-12. There was no escaping the fact that the time of year was here when I would have to change my mentality from warm-weather operations to winter operations. There are some pilots, like my friend Tim, who, rather than deal with the burdens of operating in cold climes, move to southern locales. In Tim’s case I can hardly blame him. If I think that the back seat of my Super Cruiser is cold, it must still feel tropical in comparison to the back hole of his Stearman. But those pilots who migrate to warmer

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climates in the winter don’t often get to experience the phenomenal performance that only a cold, highpressure day affords us in the wintertime. They don’t get to experience the truly CAVU skies that can only be found, at least up north, on those mid-winter days. Winter flying certainly has some wonderful benefits, but it also has some special considerations. Let’s take a look at some of them. The first consideration I’d like to mention should be a no-brainer, yet every year there are pilots who seem oblivious to the fact that airplanes will not fly very well, if at all, when the lifting surfaces have been contaminated with ice, snow, or frost. They manage to ruin perfectly fine airplanes when they crash as a result of an attempted takeoff without removing the contamination. I saw a pilot once, who started to taxi to the runway with at least 2 inches of powder snow sitting on the wings and tail of his airplane. He had thought that the snow would “blow off the wings” at the start of his takeoff roll. Fly? “NOT,” as one of my younger sons might say. So if upon your arrival at the airport on a frosty winter’s morn, you find your wings, prop, and tail feathers coated with ice, snow, or even just frost, the first order of business will be to remove it. (Of course, if your aircraft has been parked in a hangar, there might be other considerations if you find frozen contamination on your airplane.) If the tops of your wings are painted a dark color like the Tennessee Red of my Super Cruiser,

and the sun is shining, even in the depths of winter, it shouldn’t take too long for that passive solar heat to do its thing. But if your wings are a weather-beaten white, and haven’t seen a coat of wax in awhile, it could be quite some time before they are rid of their lift-defying contamination. For many years, one of my wintertime duties at the flight school where I worked was the removal of snow and ice from the tied-down airplanes on the line. It didn’t take me too long to realize how dark colors and smooth, waxed surfaces aided me in my job. Those aircraft were quickly and easily “de-iced.” But those aircraft that had old, chalky, and faded finishes sometimes had contamination stuck on their surfaces until the temperatures rose above freezing. And there were times when that might be more than several days. I do hope that you are also aware that even a thin coat of rough frost could have the potential to prevent the wings from generating enough lift to allow takeoff. So, if you find your wings frost-covered, and the sun and breeze don’t have enough strength to sublimate it (or you don’t have the time to wait for the sun to do its thing), be prepared to remove or polish the frost manually. At least while you are vigorously rubbing the wings down with an old towel, you’ll also be increasing your circulation, raising your body heat, and getting a wonderful red glow on your cheeks. Now, if it has been cold enough to leave frost, snow, or ice on your airframe, then it is probably


cold enough to warrant the preheating of your engine. There are some folks who advocate keeping the engine preheating all the time while parked, utilizing an electrical preheating device, and there are others who insist it is better to only preheat prior to each planned flight. (If only the heat generated by the arguments between these two opposing factions could be harnessed, I could easily reduce the electric bill for preheating my own airplane!) There are also those folks who prefer to use some form of forced hot air to preheat their aircraft. I guess whatever melts your candle…but regardless of how you preheat, it should be done if you care at all about extending the life of your engine, instruments, and avionics. Your engine isn’t the only thing that needs preheating; your instruments and avionics need that preheat as well. Not only is the oil in your engine sump thick, but also every moving part in your airplane is going to be sluggish. The gyros in your instruments; the cables and linkages of throttle; mixture and prop controls; and the displays on your avionics all need a preheat as well. My personal way of taking care of the preheating is to have a “Tanis” heater heating the oil sump and cylinders of the engine. I also have a small ceramic heater inside the cockpit. These are both plugged into an inexpensive 24-hour timer, which I set to turn on about four hours before my expected departure time. In this way the airplane is already warm when I get to the airport. It is rare that I have a difficult start this way. The issues of getting our cranky aviation engines started in the winter is worthy of a separate article, so I’ll deal with my techniques and the dangers associated with those techniques in the next article. In the meantime I guess I’ll go dig those long johns out of their summer storage. It’s feeling like it might be a long winter.

“You can’t learn everything from a book. The workshop provided me with the right amount of theory and hands-on practice to instill the confidence to get started on my kit.” Cecil Streeter EAA # 590681

HANDS-ON HOMEBUILDER WORKSHOP SCHEDULE Jan. 29-30

Denver, CO

• RV Assembly

Jan. 29-30

Oshkosh, WI

• Introduction to Aircraft Building • Sheet Metal Basics • Fabric Covering • Composite Construction • Electrical Systems and Avionics • Gas Welding • Test Flying your Project

Feb. 25-27

Griffin, GA (Atlanta Area)

• TIG Welding

Feb. 26-27

Lakeland, FL (Sun ’N Fun Campus)

• Introduction to Aircraft Building • Sheet Metal Basics • Fabric Covering • Composite Construction • Electrical Systems and Avionics

March 5-6

Dallas, TX

• Introduction to Aircraft Building • Sheet Metal Basics • Fabric Covering • Composite Construction • Electrical Systems and Avionics • Gas Welding

March 19-20

Watsonville, CA • Introduction to Aircraft Building • Sheet Metal Basics • Fabric Covering • Electrical Systems and Avionics


2005 01 winter operations