Skiplane Heaven

If you’re a fan of new challenges and mind-numbing cold, bolt on a pair of skis this winter and hit the snow.

Skiplane

Skiplane

The grass strip where I learned to fly in a Piper J-3 Cub in the late 1980s served as an ideal training environment for a new pilot — for about nine months out of the year, that is. In winter, the 1,900-foot turf runway would usually be covered in snow, ice, mud or sometimes a menacing combination of all three. As a result, the field would almost totally shut down for a stretch of time most winters from January through March, with only one airplane based there able to fly consistently: the little yellow J-3 Cub, its rubber tires replaced by a pair of stout wooden snow skis.

Nobody knows for sure when the first airplane equipped with skis took to the air, but we do know the practice of skiplane flying is about as old as aviation itself. If it’s indeed true that necessity is the mother of invention, the first skiplanes probably emerged right around the time early aviators in the 1910s starting getting stuck in the snow. Somewhat later, in 1955, New Zealander Sir Harry Wigley created the first set of retractable skis. Using a crude, hand-operated retraction system, Wigley’s invention allowed him to depart in his Auster Aiglet high-wing monoplane from the paved runway at Mount Cook and land on the Tasman Glacier, high up in New Zealand’s Southern Alps — with Sir Edmund Hillary riding along as one of his first passengers.

Today, skiplane flying is a popular sport in the United States among a relatively small but hearty group of aviators flying in several Northern states — and it’s an absolute necessity in many parts of the world when winter’s wrath strikes. Interestingly, the Federal Aviation Regulations don’t require any specific pilot training to fly skiplanes. Still, it’s a good idea to get checked out by a qualified instructor before trying it solo. Taking off and landing a ski-equipped airplane from packed snow isn’t much different from normal operations on a hard-surface runway. Belly-deep virgin snow, frozen lakes and sloping glaciers, on the other hand, can pose challenges that novice skiplane pilots will want to experience for the first time with an experienced flier.

One of the most challenging aspects of skiplane operations can be taxiing, especially in strong winds when ski-equipped airplanes behave more like seaplanes, with a tendency to weathervane. You’ll also need quite a bit more room to maneuver a skiplane than you might think. And you’ll sometimes even have to enlist help from wing walkers, such as when taxiing on glare ice in a strong wind.

Another consideration is the type of ski you should use. Just as there are many different types of snow surfaces you’ll encounter, there are different types of skis for the conditions. A long, wide ski is best for fresh powder, whereas a sharp, thin blade can improve performance on hard-packed snow or smooth ice. When taxiing in deep snow, you’ll have to add plenty of power to “get up on step,” similar to floatplane flying. If an airplane on skis is allowed to sink into soft snow, it can come to a halt and become immobile. That’s not such a big deal if you’re at your home airport and have friends around to help dig you out. If you’re alone in bush country, such a misstep can escalate into a life-threatening situation.

Aircraft skis can be constructed from a variety of materials, including composites, wood, aluminum or polyethylene plastic bonded to the skis' bottom surface. Some skis replace the wheels by bolting in their place, while others clamp onto the tires with the benefit of a little extra shock absorption on landing. Prices vary widely, from about $5,000 for a basic pair of skis for light-sport aircraft from companies like TrickAir in Weyauwega, Wisconsin, to nearly $30,000 for top-of-the-range retractable skis from Wipaire in St. Paul, Minnesota. Of course, used skis can be had for much less, but keep in mind a cheap set of skis might need repairs or refurbishing.

One of your first decisions before buying skis will involve the choice of whether to fly with nonpenetration retractable skis, which can be extended for snow operations and raised by a hydraulic pump or crank for operating from hard surfaces, or penetration skis (also known as wheel-skis), a simpler design whereby the wheels extend partially below the skis at all times. This compromise eliminates the need for a mechanism to raise and lower the skis, but the tradeoff means less than optimal ground clearance on hard surfaces and extra drag from wheels on snow.

Once airborne, flying a skiplane isn’t much different from flying a conventional airplane, with the exception that speed and range can be reduced by the extra drag. Your POH may also specify a lower maximum cruise speed with skis installed.

As with any kind of winter flying, you’ll want to bundle up and carry basic emergency gear — including waterproof matches, signaling devices, a shovel, a flashlight and an arctic parka — in the event of a forced landing or in case the engine won’t restart after you’ve set down at a remote location.

It’s also useful to keep in mind that, even on cloudy days, you’ll want to bring along a pair of winter sport sunglasses. Glare on snow and ice can destroy depth perception. This can be especially dangerous operating in hilly terrain, where flat light from an overcast sky can make terrain and snow mounds appear taller, shorter or wider than they really are. On bright days, glare can make it hard to see snowdrifts and other hazards.

Takeoff distances on skis are generally longer than on wheels, and they can be much longer in wet snow or powder. As you’d normally do, use headwinds and downhill slopes to help get you airborne more quickly. Many experienced skiplane pilots recommend following soft-field takeoff procedures, with a brisk acceleration during taxi onto the departure path to prevent the airplane from sinking into the snow.

In many ways, landing a skiplane is actually easier than setting down on wheels. First, you get the added benefit of feeling the skis’ trailing edges as they kiss the snow on touchdown. The snow can also cushion the landing, making even a slightly botched attempt feel like a greaser. If landing on a slope, uphill is the way to go. To avoid a hard landing, fly the airplane all the way to the surface and add some power just before touchdown. But remember to turn parallel to a steep slope before stopping — or you may find yourself sliding backward down the hill.

For more on skiplane flying, visit the enthusiasts website skiplane.org or download a copy of the FAA's excellent Seaplane, Skiplane, and Float/Ski Equipped Helicopter Operations Handbook.

For more on braving the cold, check out Robert Goyer's recent feature on winter flying.

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