Guest Post by Jim Efird, Chief Flight Instructor, Aerowood Aviation.
Winter just around the corner, and some of you have not yet had the privilege of properly preparing the airplane in the cold. You need to keep in mind that winter flying takes more patience, more time, and more work than warmer days. Give yourself plenty of time to get the airplane ready.
There are weather conditions that affect every nonhangered airplane with ice, snow, and beautiful icicles dangling from wings and control surfaces. ALL that ice and snow MUST be removed COMPLETELY before attempting flight. So how to go about it?
First, DO NOT scrape it off. Those deice scrapers they sell at Walmart and NAPA are fine for your Ford windshield, but will badly mar the plexiglass on any GA airplane and will damage the surface on wings, fuselage, empennage. Don’t even use your driver’s license or credit card. They will scratch the surface.
By far the safest and easiest way to deice the airplane is with sunshine. It is wonderful what a few minutes of sunlight will do for an ice-covered airplane, especially if the airplane is a dark color. Untie it, point the tail at the sunlight, plug in the preheater, and by the time the rest of your preflight is completed the airplane may well be clean.
You can use the brush end of that deicer, or a good broom, to get the loose snow off. Most Alaska pilots carry a janitor’s pushbroom in their car for this purpose. Given the large surfaces involved, it makes the job of cleaning a foot of snow off a lot quicker. Brush gently.
One good way to get the frost and ice off is with liquid deicer, a.k.a. alcohol. HEET, that fuel additive you’ll find in yellow bottles at the auto supply store, is 99% glycol and works great (applied with a squirt bottle) but it’s expensive. We’ve found an RV deicer that is almost straight alcohol, therefore will not damage the airplane surface or react chemically with the plexiglass. We keep that in a garden sprayer near the preheaters. More recently I found that RainX windshield washer fluid is 14% alcohol. Less alcohol, less effective, but also less expensive.
I’ve seen guys try to deice with hot water. Frankly, I think that’s foolish. It’ll get the ice off, but water running down into the control surfaces could freeze, leaving you with no control once you’re airborne.
Don’t forget the underside. Remember, lift is DOWN on the horizontal tail surfaces. Take off with frost on that nearly-invisible spot and you are a test pilot. There’s no telling what the airplane will do, but you are certain not to enjoy the ride.
So, you’re deiced and preheated and cranked up. Now what? Well, that’s the easy part. ALL your performance parameters improve when it’s cold. Shorter takeoff roll, quicker climb, better fuel burn….but you knew that already.
Flying in this kind of stuff is much safer than driving in it. With the airplanes we have a propeller and aerodynamic control, at least to some extent, even on the ground; so it is possible to operate safely with an ice-covered runway. Nevertheless, while taxiing, take it easy; give yourself plenty of time and plenty of room for the slipping and sliding that may well occur on the iced-up taxiways and runways. Be psychologically prepared to shut down, get out, and push yourself out of trouble if necessary.
In all my years flying Alaska and Chicagoland, ice never forced me off the runway, and I only aborted one takeoff (that was in a Lake Buccaneer with frozen brakes).
The tricky part of the flight is landing on an ice-covered runway; even trickier is landing on an ice-patched runway, which can create significantly out-of-balance traction. Either way, use a soft-field technique. Keep it flying as long as you can to maintain aerodynamic control as long as you can, and avoid braking. If the runway is a solid sheet of ice you won’t have any braking action anyway; and if it’s patchy ice, you may have braking action on one side but not the other. Even gentle braking under those circumstances could jerk you toward the dry side. Best to leave your feet off the brakes. Roll on past that nearby intersection and don’t try to turn off until you know you’ve got traction.
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