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Chapter-5 Stalls and Spins-V20_Sport Pilot Handbook 8/30/2021 5:56 PM Page 25

Chapter 5: Stalls and Spins 5-25

How Elevator Back Pressure Translates Into the Direction the Nose Moves

A C B

D

Fig. 33 Fig. 34
Pulling aft on the elevator in Pulling the elevator aft
straight flight moves the nose by the same amount
perpendicular to the horizon while in a descending
(arrow A). This makes it easy turn moves the nose in
to see that your angle of attack a diagonal direction to-
is increasing with the application ward the horizon (arrow B).
of elevator back pressure. This is The result is that the nose
why relatively fewer pilots accidentally moves a smaller amount vertically
stall an airplane in level flight (yes, some still do, of course). (arrow C) because it must also move horizontally, too
The vertical movement of the nose helps them understand (arrow D). This makes it harder for you to see that your angle
that they are approaching stall territory. of attack is increasing in a descending turn.
to get a very rough approximation of your angle of attack, as previously discussed in Figures 19
and 20 on page 5-14. Without knowing your angle of attack, it’s entirely possible for you to stall
with the nose pointed below the horizon. You will undoubtedly be surprised by such an event.
What further complicates this issue is that the airplane’s stalling speed increases in a turn because
of the increase in load factor (more on load factor when we cover accelerated stalls). If the airplane
stalls in this condition, you might initially be confused because the nose is pointed below the horizon
in an attitude that you normally select to recover from the stall.
To recover from a stall in a descending turn, you must do what you did before, but now it’s a lot
more counterintuitive because the nose is already below the horizon and the ground is close. Stay
true to your (flight) school. It’s just a stall. Release elevator back pressure and lower the nose, re-
ducing the angle of attack to less than its critical value. Yikes! How unnatural is that? It’s like wear-
ing swim fins with a tuxedo (and that combination doesn’t look good even on a penguin).
The closer you are to the ground, the stronger your tendency is to continue pulling back on the
elevator, despite the fact that you may be in a stall. There is a phrase for this in Spanish: Hasta la
vista, baby. And if you’d like me to complicate this equation even further, just imagine what the stall
would be like if the airplane was in a skid at the time of the stall. One wing might stall before the
other and the airplane would enter a spin. Believe me, this is not what your instructor means when
he or she says, “Let’s take the plane out for a spin.” Spinning close to the ground might easily turn
your airplane into a lawn dart. This is why you always want to fly coordinated as well as be hyper-
sensitive to the conditions that precede a stall. Most important, you don’t want to fall into the trap
of believing that just because the airplane’s nose is pointed below the horizon that it can’t stall. It
can.
Now it’s time to look a little more closely at other factors that can affect the stall characteristics
of your airplane. Among these are weight, load factor, center of gravity and airplane configuration.
Let’s examine each.