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Chapter-5 Stalls and Spins-V20_Sport Pilot Handbook 8/30/2021 5:56 PM Page 33

Chapter 5: Stalls and Spins 5-33

The Danger of Premature Flap Retraction

Fig. 38

Airplane sinks instead
of climbs because flaps
retracted all at once

Premature retraction of the flaps
can result in a secondary stall Retract half flaps, then
close to the ground or in the airplane retract remaining flaps
continuing to descend once full power in smaller increments
and climb attitude are established (as if
you are executing a go-around.

only after the flaps are being retracted and the airplane is
accelerating that you raise the nose to an attitude that allows
you to climb at Vy. Since the airplane is operating at a slow
speed with full power, you’ll also need to apply sufficient right
rudder to compensate for the airplane’s power-induced left
turning tendency.
Now comes the important question. What do you do about the flaps? If you retract them all at
once you’ll certainly reduce their drag, but you’ll also deprive the airplane of the extra lift they pro-
vide. Also, if you removed all the flaps at once, the airplane might begin sinking. As it sinks, you
might be psychologically unwilling to keep the nose lowered enough to accelerate the airplane, es-
pecially if you are close to the ground and there’s a nice big tree ahead of you. You know what that
sinking feeling means, right? Or rather, what your reaction to it means. You could enter a secondary
stall close to the ground, without much altitude for recovery. It’s tradeoff time. You first want to re-
move the portion of the flaps causing the greatest amount of drag to avoid installing a living treetop
air freshener in your cockpit.
Your airplane’s POH is the ultimate source of information about correct flap reduction procedures,
but in general:
In airplanes having 40 degrees of high-lift/high-drag flaps, you’ll typically reduce flaps to 20 de-
grees of extension (their least drag, max lift condition), followed by reducing the remaining flaps in
10-degree increments as long as the airplane is accelerating to Vy (Figure 38).
In airplanes with manually extended flaps, you’ll usually reduce the flaps to the second notch of
extension (which is typically the least drag, max lift condition unless specified otherwise by the air-
plane’s POH), followed by each remaining notch as long as the airplane is accelerating to Vy.
In airplanes having 30 degrees of moderate-lift/moderate-drag flaps, remove the last (full-flap)
notch of flaps, followed by the remaining flaps in 10-degree (or single notch) increments as long as
the airplane is accelerating to Vy.