the surface and your skiplane’s performance. Deep
snow can contribute to longer takeoff distances—by a
factor of four or five at higher gross weights—but with
thin snow and ice the takeoff roll may actually be
shorter than on wheels (taxiing on slick runways also
means crabbing into the wind and using engine power
to pull you sideways).
Remember, this is hard-core winter flying. On cold
days, as cold as the sub-zero to single-digit temps, density altitude can actually fall below actual elevation.
During our recent flying in Minnesota, density altitude
ran about - 3,000 feet mean sea level. Off the slippery,
snow-pocked surface of the St. Croix River, the Husky
seemed to depart the ice almost the same second the tail
comes up. Slick, for sure.
Experience and judgment are necessary to gauge surface conditions from a moving aircraft. Launching from
an airport into a snowy countryside, a pilot may have
some hints at conditions at the destination—
temperature, humidity, maybe snow depth—but only maybe.
Consider how a “little accumulation” in the forecast
may be on the money in one location, but may not
reflect the accumulation a few miles away. When it
comes time to land, you’ll first need to make a low pass.
Consider these suggestions for judgment tools, borne
of Mark’s experiences.
SNOWY FIELDS - WHEN landing on such surfaces, on your
low pass, get down as low and as slow as you can comfortably fly to look for potential problems. These
include bumps that might hide a rock, mounds that
could mask a tree trunk, or spots of thin snow where
ground and vegetation show through. Be mindful that
in fields and meadows, deep snow may mask that telltale fence indicator—posts; we want to avoid wires on
the ground as much as those in the air. Avoid anything
The learning tool for my skiplane adventure was EAA’s A-1C Husky 2010 sweepstakes grand prize on Wipline AirGlide skis. Many Sport Aviation readers are
already familiar with Aviat’s newest incarnation of the rugged Husky, but for this
year’s sweepstakes it comes with the retractable skis plus some other goodies.
Tops among these special touches is a year’s worth of fuel from Chevron. There
are numerous other prizes in the 2010 sweepstakes; to learn more about the
Husky and/or the other prizes, visit www.AirVenture.org/sweepstakes.
For more information on Wipaire’s skis, visit www.Wipaire.com
BEFORE YOU GO:
Are You Prepared?
It’s one thing to sample the snowy runway
options from an urban airport like Richard
E. Fleming Field (SGS) in South St. Paul,
Minnesota. We dressed for the weather,
but we didn’t fear a problem that would
force us to spend a cold night in the winter
wilderness—not with cell phone service
and scores of ice fishermen on the nearby
lakes and rivers. Out in the winter bush—
even just an hour away from the Big
City—it’s a different matter.
Heading into that wilderness today
should not mean abandoning common
sense. Be sure people know your plans.
Beyond dressing for the conditions, carry
survival gear—food, water, air-band radio,
fire-starting items, first-aid kit, flares,
and a signal mirror. Be prepared to stay a
night protected from both dehydration
and hypothermia. Hypothermia is a serious threat; don’t learn about it firsthand.