Myth #1: Flying too slowly causes stalls.
Reality:
Astute as the Brothers were, even Orville and Wilbur Wright
erroneously believed that stalling was related to slow
airspeed. Angle of attack is the defining parameter for the
stall; thus, airspeed by itself is useless as an indicator
of our margin to the stall. Yet the airspeed myth persists,
often being reinforced by the simplistic, wings-level, one-g
stalls practiced repeatedly for check rides.
Myth #2: Stalls cause spins.
Reality:
Two elements must be present in order for an airplane to
spin: stall & yaw. By themselves, neither stalling nor
yawing result in spinning; however, simultaneously stalling
with sufficient yawing always results in a spin.
Myth #3: All cross-controlled flight increases your stall /
spin potential.
Reality:
Cross-controlled flight comes in two basic flavors: skids
and slips. Skids tend to have a greater stall / spin
potential than coordinated flight. Slips, on the other hand,
tend to have a lower stall / spin potential than even
coordinated flight.
Myth #4: If you inadvertently stall or spin, just let go of
the controls.
Reality:
Aerodynamics, human factors, and the practicalities of the
situation can conspire to make this advice suspect:
-
Some light airplanes might be able to self-recover from
the early stages of some stall / spins; however, letting
go of the controls a bit later in the process, or under
a different set of conditions, may not result in
recovery at all.
-
Letting go of the controls during a surprise stall /
spin is not a natural instinct – clutching the stick or
yoke even tighter is a more common reaction.
-
The majority of stall / spin accidents occur at or below
traffic pattern altitude. Even if the airplane can
self-recover and the pilot is capable of instantly
releasing the controls, more altitude will likely be
consumed compared to a prompt application of precisely
choreographed recovery controls.
Myth #5: During recovery from upright spins, the elevator
control should not be moved forward until rotation ceases.
Reality:
Although opposite rudder alone may effect recovery in some
airplanes in the early stages of some spins, it may not be
sufficient by itself for recovery from fully developed or
aggravated spins. Therefore, pilots should not rely on
opposite rudder alone during spin recovery. Pilots should
always expect the need for full opposite rudder followed by
forward movement of the elevator control to terminate
spinning, regardless of the airplane or the type of upright
spin encountered.
Myth #6: During spins, the slip / skid indicator shows spin
direction.
Reality:
The slip / skid ball is totally unreliable when spinning.
Myth #7: The longer an airplane stays in a spin, the more
airspeed it gains and the faster it rotates.
Reality:
The spin is a high Drag maneuver. Consequently, airspeed
will not continue to increase, but will generally stabilize
at a relatively low and constant value. And once the spin
develops (usually two to four turns), rate of rotation will
stabilize as well.
Myth #8: The longer an airplane stays in a spin, the greater
the chance of structural damage.
Reality:
The spin itself is a relatively low g maneuver. A
normal upright spin, for example, imposes essentially one
g on the pilot and the airplane. It is during the
pullout following the spin recovery where significant g-load
could be generated. It’s up to the pilot to manage the g-load
to stay within design limits during the pullout.
Myth #9: Since most accidental spins occur too low for
recovery, spin training is a useless exercise.
Reality:
This myth might be true if pilots were suddenly waking up
and finding themselves spinning in an airplane. The typical
stall / spin accident is not a sudden, random event devoid
of pilot participation. Instead, it is largely a
pilot-driven process that culminates in a stall or spin
prior to ground impact. Stall / spin accidents evolve as a
chain of events with warning signs that, if recognized and
corrected, can be broken before reaching the spin.
Proficiency in the elements of a comprehensive,
scenario-based stall / spin training program should provide
pilots with the awareness and skills to prevent an
accidental spin departure in the first place.
Myth #10: Pilots with more experience are better at avoiding
fatal stall / spins than pilots with less experience.
Reality:
If “more experience” means “higher flight times and more
advanced certificates / ratings” then this assertion is
false. A study by the AOPA Air Safety Foundation revealed
that student pilots, who made up fifteen percent of active
pilot population during the years 1993-2001, were involved
in just four percent of the fatal stall / spins – a better
showing than even ATPs. Private and commercial pilots, on
the other hand, made up 61 percent of the active pilots, but
were involved in 83 percent of the fatal stall / spin
accidents.
Myth #11: As a whole, flight instructors are well qualified
to teach stalls and spins.
Reality:
Even though flight instructor applicants receive logbook
endorsements certifying that they are competent to teach
spins, published studies and anecdotal evidence reveal that
flight instructors nationwide tend neither to be well
trained in stall / spin dynamics, nor to have sufficient
hands-on experience with spins to be able to provide
meaningful spin training.
Myth #12: Spins can be hard on an airplane’s gyro
instruments.
Reality:
This claim is often cited as the reason why a particular
instructor or flight school cannot provide spin training in
an airplane approved for spins. According to senior
gyroscope technicians at TGH Aviation in Auburn, CA – an
aviation instrument and overhaul facility with more than 50
years and several hundred thousand gyroscopes of experience
behind it:
In general there would be no additional wear factors on
either an attitude gyro or a directional gyro caused by
spins. While the attitude gyro – if not caged and of the
type not designed for a full 360 degrees of movement – would
hit the mechanical stops and would experience gimbal lock,
this would not result in any appreciable additional wear
beyond what is normally expected....
As for the turn coordinator, we have seen evidence that this
instrument can realize negative effects in an aircraft that
has experienced excessive flat spins. As not many pilots are
purposely inducing flat spins on a regular basis in
airplanes equipped with turn coordinators, such negative
effects would be a rare occurrence.
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