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Old February 2nd 04, 10:33 PM
Chris OCallaghan
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Default Proper stall recovery technique

Thought I would unearth this note as it appears apropos to several
concurrent spinning threads...

This was in response, primarily, to the notion that the proper
recovery to a stall with dropping wing is to "lift" the lower wing
with rudder concurrent with stick forward, leaving the ailerons
neutral. The author stated he was unaware of any aircraft flight
manual recommending otherwise, to wit...

From the Ventus 2b Flight Manual:

Section 3.4 Stall Recovery

"On stalling whilst flying straight ahead or in a turn, normal flying
attitude is regained by frimly easing the control stick forward and,
if necessary, applying opposite rudder and aileron."

From The Student Pilot's Flight Manual (Kershner)

"Planes type-certificated under the FARs (as all US general aviation
planes are now) must meet certain rolling (ailerons) and yawing
(rudder) criteria throughout the stall. The FAA, therefore, now
encourages the use of coordinated controls to keep the wings level
during the stall."

Kershner goes on to echo your advice about favoring the stick first.
Move the stick forward first. I
couldn't agree more. But the point is that the FAA is recommending
against the use of rudder only, that is, the way we are still taught
(in glding). In fact, simultaneous movements should be sufficient,
though a slight hesitation after releasing back pressure is the better
habit.

A one size fits all solution is fine in the context of protecting a
student from his ignorance. If the student, due to his inexperience,
fails to recognize and react properly early in the stall and even
possibly abuses the controls, spin recovery actions are beneficial.
But it serves the experienced pilot little if it perpetuates his
ignorance. And far worse if it becomes a crutch for an instructor who
cannot or will not effectively teach and demand flawless execution of
stall recognition and appropriate recovery skills from his students.

Modern aircraft will maintain control effectiveness (even if much
decreased) into the stall. The danger we all understand: exponentially
increasing drag at the wing tip as angle of attack increases. Add to
that the weakened effect of the vertical stab and rudder due to low
airspeed, and the primary concern becomes keeping the glider from
autorotating.

A strong rudder movement at low airspeed is an absolute necessity to
keep the yaw string straight even for small aileron movements. But its
purpose is to compensate for asymmetric drag at the wingtips. This may
or may not have the effect of checking a rolling motion, but this
effect
is secondary. Roll is not the primary reason we use the rudder. And
shouldn't be taught as such. Granted, this goes against much of what
we've been teaching in gliding for many, many years. But that doesn't
make our way right. It deserves some attention.

I'll finish this note with a quote from the FAA Flight Training
Handbook:

[after brief discussion of use of aileron during stall...]

"Even though excessive aileron pressure may have been applied, a spin
will not occur if the directional (yaw) control is maintained by
timely application of coordinated rudder pressure. Therefore, it is
important that the rudder be used properly during both the entry and
recovery from a stall. Thus, the primary use or the rudder in stall
recoveries is to conteract any tendency of the airplane to yaw. The
correct recovery technique then, would be to decrease the pitch
attitude by applying forward elevator pressure to break the stall,
advancing the throttle to increase airspeed, and SIMULTANEOUSLY
maintaining direction with COORDINATED use of aileron and rudder."

(First emphasis is mine. Second is the FAA's.)