Sunday, February 22, 2009

Recovery Phase


The recovery phase occurs when the angle of attack of
the wings decreases below the critical angle of attack
and autorotation slows. Then the nose steepens and
rotation stops. This phase may last for a quarter turn to
several turns.



To recover, control inputs are initiated to disrupt the
spin equilibrium by stopping the rotation and stall. To
accomplish spin recovery, the manufacturer's

recommended procedures should be followed. In the
absence of the manufacturer's recommended spin
recovery procedures and techniques, the following
spin recovery procedures are recommended.




      Step 1—REDUCE THE POWER (THROTTLE)
      TO IDLE
      . Power aggravates the spin
      characteristics. It usually results in a flatter spin
      attitude and increased rotation rates.



      Step 2—POSITION THE AILERONS TO
      NEUTRAL
      . Ailerons may have an adverse effect
      on spin recovery. Aileron control in the direction
      of the spin may speed up the rate of rotation and
      delay the recovery. Aileron control opposite the
      direction of the spin may cause the down aileron
      to move the wing deeper into the stall and
      aggravate the situation. The best procedure is to
      ensure that the ailerons are neutral.



      Step 3—APPLY FULL OPPOSITE RUDDER
      AGAINST THE ROTATION
      . Make sure that full
      (against the stop) opposite rudder has been
      applied.



      Step 4—APPLY A POSITIVE AND BRISK,
      STRAIGHT FORWARD MOVEMENT OF THE
      ELEVATOR CONTROL FORWARD OF THE
      NEUTRAL TO BREAK THE STALL
      . This
      should be done immediately after full rudder
      application. The forceful movement of the
      elevator will decrease the excessive angle of attack
      and break the stall. The controls should be held
      firmly in this position. When the stall is "broken,"
      the spinning will stop.



      Step 5—AFTER SPIN ROTATION STOPS,
      NEUTRALIZE THE RUDDER
      . If the rudder is
      not neutralized at this time, the ensuing increased
      airspeed acting upon a deflected rudder will cause
      a yawing or skidding effect.



      Slow and overly cautious control movements
      during spin recovery must be avoided. In certain
      cases it has been found that such movements result
      in the airplane continuing to spin indefinitely, even
      with anti-spin inputs. A brisk and positive
      technique, on the other hand, results in a more
      positive spin recovery.



      Step 6—BEGIN APPLYING BACK-ELEVATOR
      PRESSURE TO RAISE THE NOSE TO LEVEL
      FLIGHT
      . Caution must be used not to apply
      excessive back-elevator pressure after the rotation
      stops. Excessive back-elevator pressure can cause
      a secondary stall and result in another spin. Care
      should be taken not to exceed the "G" load limits
      and airspeed limitations during recovery. If the

      flaps and/or retractable landing gear are extended
      prior to the spin, they should be retracted as soon
      as possible after spin entry.



It is important to remember that the above spin
recovery procedures and techniques are recommended
for use only in the absence of the manufacturer's
procedures. Before any pilot attempts to begin spin
training, that pilot must be familiar with the procedures
provided by the manufacturer for spin recovery.



The most common problems in spin recovery include
pilot confusion as to the direction of spin rotation and
whether the maneuver is a spin versus spiral. If the
airspeed is increasing, the airplane is no longer in a
spin but in a spiral. In a spin, the airplane is stalled.
The indicated airspeed, therefore, should reflect
stall speed.

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