AOPA Pilot Magazine - April 2019 - 104

P&E

TECHNIQUE

D.C.

ELECTRIC

D.C.

ELECTRIC

SLIP

R
2 MIN.
NO PITCH

INFORMATION

SKID

D.C.

ELECTRIC

R
2 MIN.
NO PITCH

INFORMATION

Figure
3. During
a slip, the
raised
wing has wing
a higher angle
and
THERE IS ONLY ONE WAY to be perfectly
DURING
A SLIP,
the
raised
hasofaattack
higher
Figure 2. There is only one way to be perfectly coordinated but infinitely many ways tostalls first resulting in an "over the top" spin entry.
coordinated
but
infinitely
more
ways
slip (yellow)
or skid (red). For
many
general aviation
airplanes,
pushing forward on theangle of attack and stalls first resulting in
yoke/stick is at least as important as the rudder input.

to slip (yellow) or skid (red). For many
general aviation airplanes, pushing
forward on the yoke/stick is at least as
important as the rudder input.

an "over the top" spin entry.

IN THE CLASSIC BASE-TO-FINAL SPIN ENTRY, the lower wing stalls first and the aircraft is

upside down immediately. No one should see this view turning onto the final approach
segment.

Coordination forms the razor-thin dividing line
between slipping and skidding flight.

See how a skidding stall quickly inverts the aircraft and how the yaw
string and the inclinometer in the turn coordinator often give the same
information, in two online videos.
www.aceaerobaticschool.com/videos

104 | AOPA PILOT April 2019

R
2 MIN.
NO PITCH

INFORMATION

Figure 4. During a skid, the lowered wing has a higher angle of attack

DURING
A resulting
SKID,inthe
lowered
wing
has a
and stalls first
an "under
the bottom"
spin entry.

higher angle of attack and stalls first
resulting in an "under the bottom" spin
entry.

stalls first, and the airplane may enter an
"over the top" spin (see above). Slipping
is an effective technique to combat a
crosswind on landing or to lose altitude
without picking up unwanted airspeed on
final. But stalling during a slip can result
in a spin, so take care to ensure that the
angle of attack stays low when close to the
ground.
During a skidding turn, the lowered
wing has a higher angle of attack; it stalls
first and the result is an "under the bottom" spin entry (see above). Your body
can detect this lack of coordination as
well since, in a skid, it's pushed to the
outside of the turn. The same is true in
a car: make a left turn on unbanked road
and your body, just like the inclinometer ball in a skid, slides toward the right.
What feels natural in a car, though, should
never feel so in an airplane. While a slip
is a valuable flight maneuver, there is no
virtue in a skid.
Still, accident reports show that
pilots skid with disappointing regularity.
The classic scenario is the traffic pattern
base-to-final turn in which, possibly exacerbated by a tailwind on base, the aircraft
is about to overshoot the extended runway
centerline. Using excessive inside rudder
to swing the nose of the aircraft toward
the runway results in a dangerous skid
in which the low wing stalls first. A skidding stall means the airplane is quickly

http://www.aceaerobaticschool.com/videos

AOPA Pilot Magazine - April 2019

Table of Contents for the Digital Edition of AOPA Pilot Magazine - April 2019