Private Pilot Flight Training and Instruction
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Sources of Inadvertent Stalls Becoming Spins
1. Inadequate rudder application in steep climbs. Climb power
raises nose, decreases airspeed and increases P-factor.
2. False concept of air speed when on base due to a tailwind.
Peripheral vision can sense the illusion and send it to the brain.
3. Letting nose pitch up and airspeed drop when applying power.
4. Having aircraft enter 'reverse command' area in pattern. A
speed so slow and power so high that the only recourse is to lower
the nose for flying speed.
5. Use of rudder to increase rate of turn from base to final.
Keep ball centered during turns.
6. Distractions from primary purpose of aircraft control. This
is now a required part of the flight test.
7. Trying to stretch a glide at a speed below best glide speed.
If you don't know best glide, use best climb. It will be close.
8. Attempting to return to runway after engine failure. Practice
at altitude and then add 50% fudge factor.
Stalls do not cause spins. A spin is initiated where the pilot
includes or fails to include, rudder, aileron, or power individually
or in combination during a stall. Auto rotation occurs from an
asymmetrical stall and a sideslip. There is an abrupt loss of
control when leaving the stall and entering the spin. The untrained
pilot will always react instinctively and apply controls incorrectly
thus aggravating the spin entry.
An incipient phase occurs when the foregoing stall is accompanied
by uncoordinated yawing. The yaw induces a roll due to increased
asymmetric lift on the wing opposite to the applied rudder. The
aerodynamic differences from uncoordinated stalled flight causes
the nose to drop. The autorotation to follow is quite varied as
long as the dynamic and inertial forces are unbalanced. Airspeed
will be changing but the faster the entry the longer it takes
to stabilize the spin. By the second turn we may be in a developed
(stabilized) spin. IAS will be pegged a few miles above 1G stall
speed. Descent will vary but can reach 7500' fpm.
Know how to recognize the beginning of a spin. Quickly apply the
proper control input. Get out of the incipient spin before it
has a chance to develop. In a developed spin an aircraft prohibited
for spins may be unrecoverable. To prevent this development from
occurring the recognition and recovery from an incipient spin
is a desirable training goal. The first turn of a spin causes
the greatest loss of altitude, as much as 800' to 1000'. High-density
altitude causes faster rate of spin and greater loss of altitude.
Recovery: Immediately, power off, opposite rudder, forward on
yoke always in this sequence. If rudder is effective yoke forward
may not be necessary. Otherwise, hold full application of controls
until recovery. Check turn coordinator for direction if in doubt.
The proper recovery from the incipient spin must be initiated
at once or the yaw rate will become faster and the nose more toward
the vertical.
Written by Gene Whitt
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