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Stall and Spin Awareness Training



                              ADVISORY CIRCULAR

          AC No:  61-67B

           Date:  5/17/91

       Initiated
             by:  AFS-840

         Change:

        Subject:  STALL AND SPIN AWARENESS TRAINING

      1.  PURPOSE.  This advisory circular (AC) explains the stall and
      spin awareness training required under Part 61 of the Federal
      Aviation Regulations (FAR) and offers guidance to flight
      instructors who provide that training.  In addition, this AC
      informs pilots of the airworthiness standards for the type
      certification of small airplanes prescribed in FAR Section 23.221
      concerning spin maneuvers and it emphasizes the importance of
      observing restrictions that prohibit the intentional spinning of
      certain airplanes.

      2.  CANCELLATION.  AC 61-67A, dated October 8, 1982, and AC 61-
      92 dated January 25, 1980, are canceled.

      3.  RELATED READING MATERIAL.

          a.  Report No. FAA-RD-77-26, General Aviation Pilot Stall
      Awareness Training Study.  This document may be purchased from
      the National Technical Information Service (NTIS), U.S.
      Department of Commerce, 5285 Port Royal Road, Springfield,
      Virginia 22161.  Telephone orders:  (703) 487-4650.  NTIS
      identification number ADA041310.

          b.  The following documents may be purchased from the
      Superintendent of Documents, U.S. Government Printing Office,
      Washington, D.C. 20402:

              (1)  AC 61-21, Flight Training Handbook, current edition.

              (2)  AC 91-23, Pilot's Weight and Balance Handbook,
      current edition.

              (3)  FAA-S-8081-1, Private Pilot - Practical Test
      Standards, current edition.

              (4)  FAA-S-8081-2, Commercial Pilot - Practical Test
      Standards, current edition.

              (5)  FAA-S-8081-6, Flight Instructor - Airplane Practical
      Test Standards, current edition.

      4.  BACKGROUND.  In January 1980, the Federal Aviation
      Administration (FAA) issued AC 61-92, "Use of Distractions During
      Pilot Certification Flight Tests," announcing its policy of
      incorporating the use of certain distractions during the
      performance of flight test maneuvers.

      This policy came about as a result of Report No. FAA-RD-77-26
      which revealed that stall/spin related accidents accounted for
      approximately one-quarter of all fatal general aviation
      accidents.  National Transportation Safety Board statistics
      indicate that most stall/spin accidents result when a pilot is
      distracted momentarily from the primary task of flying the
      aircraft.

      5.  CHANGES.  Changes to FAR Part 61, completed in 1991, included
      increased stall and spin awareness training for applicants for
      recreational, private, and commercial pilot certificates.  The
      training is intended to emphasize recognition of situations that
      could lead to an inadvertent stall and/or spin by using realistic
      distractions such as those suggested in Report No. FAA-RD-77-26
      and incorporated into the performance of flight test maneuvers.
      Although the training is intended to emphasize stall spin
      awareness and recovery techniques for all pilots, only flight
      instructor-airplane and flight instructor-glider candidates are
      required to demonstrate instructional proficiency in spin entry,
      spins, and spin recovery techniques as a requirement for
      certification.  Where applicable, AC 61-67B supersedes AC 61-
      21A.

      6.  COMMENTS INVITED.  Comments regarding this publication should
      be directed to:

          Federal Aviation Administration
          Field Programs Division, AFS-500
          Advisory Circular Staff
          P.O. Box 20034, Gateway Building
          Dulles International Airport
          Washington, DC 20041-2034

      Every comment will not necessarily generate a direct
      acknowledgement to the commenter.  Comments received will be
      considered in the development of upcoming revisions to AC's or
      other related technical material.
   
 

      /s/ William C. Withycombe
          Acting Director, Flight Standards Service


                                  CONTENTS

                                                               Page No.

      CHAPTER 1.  GROUND TRAINING - STALL AND SPIN AWARENESS ....  1

       1.  DEFINITIONS ..........................................  1
       2.  DISTRACTIONS .........................................  3
       3.  STALL RECOGNITION ....................................  3
       4.  TYPES OF STALLS ......................................  4
       5.  STALL RECOVERY .......................................  4
       6.  SECONDARY STALLS .....................................  4
       7.  SPINS ................................................  4
       8.  WEIGHT AND BALANCE ...................................  5
       9.  PRIMARY CAUSE ........................................  5
      10.  TYPES OF SPINS .......................................  5
      11.  SPIN RECOVERY ........................................  5

      CHAPTER 2.  FLIGHT TRAINING - STALLS ......................  7

      12.  STALL TRAINING .......................................  7

      CHAPTER 3.  FLIGHT TRAINING - SPINS ....................... 11

      13.  SPIN TRAINING ........................................ 11

      CHAPTER 14.  AIRWORTHINESS STANDARDS ...................... 13

      14.  OPERATING LIMITATIONS ................................ 13
      15.  PLACARDS ............................................. 14
      16.  PILOT AWARENESS ...................................... 14


           CHAPTER 1.  GROUND TRAINING - STALL AND SPIN AWARENESS

      1.  DEFINITIONS.  A stall is a loss of lift and increase in drag
      that occurs when an aircraft is flown at an angle of attack
      greater than the angle for maximum lift.  If recovery from a
      stall is not effected in a timely and appropriate manner by
      reducing the angle of attack, a secondary stall and/or spin may
      result.  All spins are preceded by a stall on at least part of
         the wing.  The angle of the relative wind is determined primarily
      by the aircraft's airspeed.  Other factors are considered, such
      as aircraft weight, center of gravity, configuration, and the
      amount of acceleration used in a turn.  The speed at which the
      critical angle of the relative wind is exceeded is the stall
      speed.  Stall speeds are listed in the Airplane Flight Manual
      (AFM) or the Pilot Operating handbook (POH) and pertain to
      certain conditions or aircraft configurations, e.g., landing
      configuration.  Other specific operational speeds are calculated
      based upon the aircraft's stall speed in the landing
      configuration.  Airspeed values specified in the AFM or POH may
      vary under different circumstances.  Factors such as weight,
      center of gravity, altitude, temperature, turbulence, and the
      presence of snow, ice, or frost on the wings will affect an
      aircraft's stall speed.  To thoroughly understand the stall/spin
      phenomenon, some basic factors affecting aircraft aerodynamics
      and flight should be reviewed with particular emphasis on their
      relation to stall speeds.  (This advisory circular is principally
      concerned with and discusses airplanes.  However, much of the
      information also is applicable to gliders.)  The following terms
      are defined as they relate to stalls/spins.

          a.  Angle of Attack.  Angle of attack is the angle at which
      the wing meets the relative wind.  The angle of attack must be
      small enough to allow attached airflow over and under the airfoil
      to produce lift.  A change in angle of attack will affect the
      amount of lift that is produced.  An excessive angle of attack
      will eventually disrupt the flow of air over the airfoil.  If the
      angle of attack is not reduced, a section of the airfoil will
      reach its critical angle of attack, lose lift, and stall.
      Exceeding the critical angle of attack for a particular airfoil
      section will always result in a stall.

          b.  Airspeed.  Airspeed is controlled primarily by the
      elevator or longitudinal control position for a given
      configuration and power.  If an airplane's speed is too slow, the
      angle of attack required for level flight will be so large that
      the air can no longer follow the upper curvature of the wing.
      The result is a separation of airflow from the wing, loss of
      lift, a large increase in drag, and eventually a stall if the
      angle of attack is not reduced.  The stall is the result of
      excessive angle of attack - not airspeed.  A stall can occur at
      any airspeed, in any attitude, and at any power setting.

          c.  Configuration.  Flaps, landing gear, and other
      configuring devices can affect an airplane's stall speed.
      Extension of flaps and/or landing gear in flight will usually
      increase drag.  Flap extension will generally increase the
         lifting ability of the wings, thus reducing the airplane's stall
      speed.  The effect of flaps on an airplane's stall speed can be
      seen by markings on the airplane's airspeed indicator, where the
      lower airspeed limit of the white arc (power-off stall speed with
      gear and flaps in the landing configuration) is less than the
      lower airspeed limit of the green arc (power-off stall speed in
      the clean configuration).

          d.  V sub so.  V sub so means the stall speed or the minimum
      steady flight speed in the landing configuration.

          e.  V sub s1.  V sub s1 means the stall speed or the minimum
      steady flight speed obtained in a specific configuration.

          f.  V sub A.  V sub A is the design maneuvering speed which
      is the speed at which an airplane can be stalled without
      exceeding its structural limits.

          g.  Load Factor.  Load factor is the ratio of the lifting
      force produced by the wings to the actual weight of the airplane
      and its contents.  Load factors are usually expressed in terms of
      "G."  The aircraft's stall speed increases in proportion to the
      square root of the load factor.  For example, an airplane that
      has a normal unaccelerated stall speed of 45 knots can be stalled
      at 90 knots when subjected to a load factor of 4 G's.  The
      possibility of inadvertently stalling the airplane by increasing
      the load factor (by putting the airplane in a steep turn or
      spiral, for example) is therefore much greater than in normal
      cruise flight.  A stall entered from straight and level flight or
      from an unaccelerated straight climb will not produce additional
      load factors.  In a constant rate turn, increased load factors
      will cause an airplane's stall speed to increase as the angle of
      bank increases.  Excessively steep banks should be avoided
      because the airplane will stall at a much higher speed or, if the
      aircraft exceeds maneuvering speed, structural damage to the
      aircraft may result before it stalls.  If the nose falls during a
      steep turn, the pilot might attempt to raise it to the level
      flight attitude without shallowing the bank.  This situation
      tightens the turn and can lead to a diving spiral.  A feeling of
      weightlessness will result if a stall recovery is performed by
      abruptly pushing the elevator control forward, which will reduce
      the up load on the wings.  Recoveries from stalls and spins
      involve a tradeoff between loss of altitude (and an increase in
      airspeed) and an increase in load factor in the pullup.  However,
      recovery from the dive following spin recovery generally causes
      higher airspeeds and consequently higher load factors than stall
      recoveries due to the much lower position of the nose.
      Significant load factor increases are sometimes induced during
         pullup after recovery from a stall or spin.  It should be noted
      that structural damage can result from the high load factors
      imposed by intentional stalls practiced above the airplane's
      design maneuvering speed.

          h.  Center of Gravity (CG).  The CG location has an indirect
      effect on the effective lift and angle of attack of the wing, the
      amount and direction of force on the tail, and the degree of
      stabilizer deflection needed to supply the proper tail force for
      equilibrium.  The CG position, therefore, has a significant
      effect on stability and stall/spin recovery.  As the CG is moved
      aft, the amount of elevator deflection will be reduced.  An
      increased angle of attack will be achieved with less elevator
      control force.  This could make the entry into inadvertent stalls
      easier, and during the subsequent recovery, it would be easier to
      generate higher load factors, due to the reduced forces.  In an
      airplane with an extremely aft CG, very light back elevator
      control forces may lead to inadvertent stall entries and if a
      spin is entered, the balance of forces on the airplane may result
      in a flat spin.  Recovery from a flat spin is often impossible.
      A forward CG location will often cause the stalling angle of
      attack to be reached at a higher airspeed.  Increased back
      elevator control force is generally required with a forward CG
      location.

          i.  Weight.  Although the distribution of weight has the most
      direct effect on stability, increased gross weight can also have
      an effect on an aircraft's flight characteristics, regardless of
      the CG position.  As the weight of the airplane is increased, the
      stall speed increases.  The increased weight requires a higher
      angle of attack to produce additional lift to support the weight.

          j.  Altitude and Temperature.  Altitude has little or no
      effect on an airplane's indicated stall speed.  Thinner air at
      higher altitudes will result in decreased aircraft performance
      and a higher true airspeed for a given indicated airspeed.
      Higher than standard temperatures will also contribute to
      increased true airspeed.  However, the higher true airspeed has
      no effect on indicated approach or stall speeds.  The
      manufacturer's recommended indicated airspeeds should therefore
      be maintained during the landing approach, regardless of the
      elevation or the density at the airport of landing.

          k.  Snow, Ice or Frost on the Wings.  Even a small
      accumulation of snow, ice or frost on an aircraft's surface can
      cause an increase in that aircraft's stall speed.  Such
      accumulation changes the shape of the wing, disrupting the smooth
      flow of air over the surface and, consequently, increasing drag
         and decreasing lift.  Flight should not be attempted when snow,
      ice, or frost has accumulated on the aircraft surfaces.

          l.  Turbulence.  Turbulence can cause an aircraft to stall at
      a significantly higher airspeed than in stable conditions.  A
      vertical gust or windshear can cause a sudden change in the
      relative wind, and result in an abrupt increase in angle of
      attack.  Although a gust may not be maintained long enough for a
      stall to develop, the aircraft may stall while the pilot is
      attempting to control the flightpath, particularly during an
      approach in gusty conditions.  When flying in moderate to severe
      turbulence or strong crosswinds, a higher than normal approach
      speed should be maintained.  In cruise flight in moderate or
      severe turbulence, an airspeed well above the indicated stall
      speed and below maneuvering speed should be used.

      2.  DISTRACTIONS.  Improper airspeed management resulting in
      stalls are most likely to occur when the pilot is distracted by
      one or more other tasks, such as locating a checklist or
      attempting a restart after an engine failure; flying a traffic
      pattern on a windy day; reading a chart or making fuel and/or
      distance calculations; or attempting to retrieve items from the
      floor, back seat, or glove compartment.  Pilots at all skill
      levels should be aware of the increased risk of entering into an
      inadvertent stall or spin while performing tasks that are
      secondary to controlling the aircraft.

      3.  STALL RECOGNITION.  There are several ways to recognize that
      a stall is impending before it actually occurs.  When one or more
      of these indicators is noted, initiation of a recovery should be
      instinctive (unless a full stall is being practiced intentionally
      from an altitude that allows recovery above 1,500 feet above
      ground level (AGL) for single-engine airplanes and 3,000 feet AGL
      for multiengine airplanes).  One indication of a stall is a mushy
      feeling in the controls and less control effect as the aircraft's
      speed is reduced.  This reduction in control effectiveness is
      attributed in part to reduced airflow over the flight control
      surfaces.  In fixed-pitch propeller airplanes, a loss of
      revolutions per minute (RPM) may be evident when approaching a
      stall in power-on conditions.  For both airplanes and gliders, a
      reduction in the sound of air flowing along the fuselage is
      usually evident.  Just before the stall occurs, buffeting,
      uncontrollable pitching, or vibrations may begin.  Many aircraft
      are equipped with stall warning devices that will alert the pilot
      when the airflow over the wing(s) approaches a point that will
      not allow lift to be sustained.  Finally, kinesthesia (the
      sensing of changes in direction or speed of motion), when
      properly learned and developed, will warn the pilot of a decrease
         in speed or the beginning of a "mushing" of the aircraft.  These
      preliminary indications serve as a warning to the pilot to
      increase airspeed by adding power, and/or lowering the nose,
      and/or decreasing the angle of bank.

      4.  TYPES OF STALLS.  Stalls can be practiced both with and
      without power.  Stalls should be practiced to familiarize the
      student with the aircraft's particular stall characteristics
      without putting the aircraft into a potentially dangerous
      condition.  In multiengine airplanes, single-engine stalls must
      be avoided.  A description of some different types of stalls
      follows:

          a.  Power-off stalls (also known as approach-to-landing
      stalls) are practiced to simulate normal approach-to-landing
      conditions and configuration.  Many stall/spin accidents have
      occurred in these power-off situations, such as crossed control
      turns from base leg to final approach (resulting in a skidding or
      slipping turn); attempting to recover from a high sink rate on
      final approach by using only an increased pitch attitude; and
      improper airspeed control on final approach or in other segments
      of the traffic pattern.

          b.  Power-on stalls (also known as departure stalls) are
      practiced to simulate takeoff and climb-out conditions and
      configuration.  Many stall/spin accidents have occurred during
      these phases of flight, particularly during go-arounds.  A causal
      factor in such accidents has been the pilot's failure to maintain
      positive control due to a nose-high trim setting or premature
      flap retraction.  Failure to maintain positive control during
      short field takeoffs has also been an accident causal factor.

          c.  Accelerated stalls can occur at higher-than-normal
      airspeeds due to abrupt and/or excessive control applications.
      These stalls may occur in steep turns, pullups, or other abrupt
      changes in flightpath.  Accelerated stalls usually are more
      severe than unaccelerated stalls and are often expected because
      they occur at higher-than-normal airspeeds.

      5.  STALL RECOVERY.  The key factor in recovery from a stall is
      regaining positive control of the aircraft by reducing the angle
      of attack.  At the first indication of a stall, the aircraft
      angle of attack must be decreased to allow the wings to regain
      lift.  Every aircraft in upright flight may require a different
      amount of forward pressure to regain lift.  It should be noted
      that too much forward pressure can hinder recovery by imposing a
      negative load on the wing.  The next step in recovering from a
      stall is to smoothly apply maximum allowable power (if
         applicable) to increase the airspeed and to minimize the loss of
      altitude.  Certain high performance airplanes may require only an
      increase in thrust and relaxation of the back pressure on the
      yoke to effect recovery.  As airspeed increases and the recovery
      is completed, power should be adjusted to return the airplane to
      the desired flight condition.  Straight and level flight should
      be established with full coordinated use of the controls.  The
      airspeed indicator or tachometer, if installed, should never be
      allowed to reach their high-speed red lines at anytime during a
      practice stall.

      6.  SECONDARY STALLS.  If recovery from a stall is not made
      properly, a secondary stall or a spin may result.  A secondary
      stall is caused by attempting to hasten the completion of a stall
      recovery before the aircraft has regained sufficient flying
      speed.  When this stall occurs, the back elevator pressure should
      again be released just as in a normal stall recovery.  When
      sufficient airspeed has been regained, the aircraft can then be
      returned to straight-and-level flight.

      7.  SPINS.  A spin in a small airplane or glider is a controlled
      or uncontrolled maneuver in which the glider or airplane descends
      in a helical path while flying at an angle of attack greater than
      the angle of maximum lift.  Spins result from aggravated stalls
      in either a slip or a skid.  If a stall does not occur, a spin
      cannot occur.  In a stall, one wing will often drop before the
      other and the nose will yaw in the direction of the low wing.

      8.  WEIGHT AND BALANCE.  Minor weight or balance changes can
      affect an aircraft's spin characteristics.  For example, the
      addition of a suitcase in the aft baggage compartment will affect
      the weight and balance of the aircraft.  An aircraft that may be
      difficult to spin intentionally in the utility category
      (restricted aft CG and reduced weight) could have less resistance
      to spin entry in the normal category (less restricted aft CG and
      increased weight) due to its ability to generate a higher angle
      of attack and increased load factor.  Furthermore, an aircraft
      that is approved for spins in the utility category, but loaded in
      the normal category, may not recover from a spin that is allowed
      to progress beyond one turn.

      9.  PRIMARY CAUSE.  The primary cause of an inadvertent spin is
      exceeding the critical angle of attack for a given stall speed
      while executing a turn with excessive or insufficient rudder,
      and, to a lesser extent, aileron.  In an uncoordinated maneuver,
      the pitot/static instruments, especially the altimeter and
      airspeed indicator, are unreliable due to the uneven distribution
      of air pressure over the fuselage.  The pilot may not be aware
         that a critical angle of attack has been exceeded until the stall
      warning device activates.  If a stall recovery is not promptly
      initiated, the airplane is more likely to enter an inadvertent
      spin.  The spin that occurs from cross controlling an aircraft
      usually results in rotation in the direction of the rudder being
      applied, regardless of which wing tip is raised.  In a skidding
      turn, where both aileron and rudder are applied in the same
      direction, rotation will be in the direction the controls are
      applied.  However, in a slipping turn, where opposite aileron is
      held against the rudder, the resultant spin will usually occur in
      the direction opposite the aileron that is being applied.

      10.  TYPES OF SPINS.

           a.  An incipient spin is that portion of a spin from the
      time the airplane stalls and rotation starts, until the spin
      becomes fully developed.  Incipient spins that are not allowed to
      develop into a steady spin are commonly used as an introduction
      to spin training and recovery techniques.

           b.  A fully developed spin occurs when the aircraft angular
      rotation rates, airspeed, and vertical speed are stabilized from
      turn-to-turn in a flightpath that is close to vertical.

           c.  A flat spin is characterized by a near level pitch and
      roll attitude with the spin axis near the CG of the airplane.
      Recovery from a flat spin may be extremely difficult and, in some
      cases, impossible.

      11.  SPIN RECOVERY.  Before flying any aircraft, in which spins
      are to be conducted, the pilot should be familiar with the
      operating characteristics and standard operating procedures,
      including spin recovery techniques, specified in the approved AFM
      or POH.  The first step in recovering from an upright spin is to
      close the throttle completely to eliminate power and minimize the
      loss of altitude.  If the particular aircraft spin recovery
      techniques are not known, the next step is to neutralize the
      ailerons, determine the direction of the turn, and supply full
      opposite rudder.  When the rotation slows, briskly move the
      elevator control forward to approximately the neutral position.
      Some aircraft require merely a relaxation of back pressure;
      others require full forward elevator control pressure.  Forward
      movement of the elevator control will decrease the angle of
      attack.  Once the stall is broken, the spinning will stop.
      Neutralize the rudder when the spinning stops to avoid entering a
      spin in the opposite direction.  When the rudder is neutralized,
      gradually apply enough aft elevator pressure to return to level
      flight.  Too much or abrupt aft elevator pressure and/or
         application of rudder and ailerons during the recovery can result
      in a secondary stall and possibly another spin.  If the spin is
      being performed in an airplane, the engine will sometimes stop
      developing power due to centrifugal force acting on the fuel in
      the airplane's tanks causing fuel interruption.  It is,
      therefore, recommended to assume that power is not available when
      practicing spin recovery.  As a rough estimate, an altitude loss
      of approximately 500 feet per each 3-second turn can be expected
      in most small aircraft in which spins are authorized.  Greater
      losses can be expected at higher density altitudes.


                    CHAPTER 2.  FLIGHT TRAINING - STALLS

      12.  STALL TRAINING.  Flight instructor-airplane and flight
      instructor-glider applicants must be able to give stall training.
      The flight instructor should emphasize that techniques and
      procedures for each aircraft may differ and that pilots should be
      aware of the flight characteristics of each aircraft flown.
      Single-engine stalls should not be demonstrated or practiced in
      multiengine airplanes.  Engine-out minimum control speed
      demonstrations in multiengine airplanes should not be attempted
      when the density altitude and temperature are such that the
      engine-out minimum control speed is close to the stall speed,
      since loss of directional or lateral control could result.  The
      flight training required by FAR Part 61 does not entail the
      actual practicing of spins for other than flight instructor-
      airplane and flight instructor-glider applicants, but emphasizes
      stall and spin avoidance.  The most effective training method
      contained in Report No. FAA-RD-77-26 is the simulation of
      scenarios that can lead to inadvertent stalls by creating
      distractions while the student is practicing certain maneuvers.
      Stall demonstrations and practice, including maneuvering during
      slow flight and other maneuvers with distractions that can lead
      to inadvertent stalls, should be conducted at a sufficient
      altitude to enable recovery above 1,500 feet AGL in single-
      engine airplanes and 3,000 feet AGL in multiengine airplanes.
      The following training elements are based on Report No. FAA-RD-
      77-26:

          a.  Stall Avoidance Practice at Slow Airspeeds.

              (1)  Assign a heading and an altitude.  Have the student
      reduce power and slow to an airspeed just above the stall speed,
      using trim as necessary.

              (2)  Have the student maintain heading and altitude with
      the stall warning device activated.
   
              (3)  Demonstrate the effect of elevator trim (use neutral
      and full nose-up settings) and rudder trim, if available.

              (4)  Note the left turning tendency and rudder
      effectiveness for lateral/directional control.

              (5)  Emphasize how right rudder pressure is necessary to
      center the ball indicator and maintain heading.

              (6)  Release the rudder and advise the student to observe
      to the left yaw.

              (7)  Adverse yaw demonstration.  While at a low airspeed,
      have the student enter left and right turns without using rudder
      pedals.

              (8)  Have the student practice turns, climbs, and
      descents at low airspeeds.

              (9)  Demonstrate the proper flap extension and retraction
      procedures while in level flight to avoid a stall at low
      airspeeds.  Note the change in stall speeds with flaps extended
      and retracted.

             (10)  Realistic distractions at low airspeeds.  Give the
      student a task to perform while flying at a low airspeed.
      Instruct the student to divide his/her attention between the task
      and flying the aircraft to maintain control and avoid a stall.
      The following distractions can be used:

                   (i)     Drop a pencil.  Ask the student to pick it
      up.  Ask the student to determine a heading to an airport using a
      chart.

                   (ii)    Ask the student to reset the clock to
      Universal Coordinated Time.

                   (iii)   Ask the student to get something from the
      back seat.

                   (iv)    Ask the student to read the outside air
      temperature.

                   (v)     Ask the student to call the Flight Service
      Station (FSS) for weather information.

                   (vi)    Ask the student to compute true airspeed
         with a flight computer.

                   (vii)   Ask the student to identify terrain or
      objects on the ground.

                   (viii)  Ask the student to identify a field suitable
      for forced landing.

                   (ix)    Have the student climb 200 feet and maintain
      altitude, then descend 200 feet and maintain altitude.

                   (x)     Have the student reverse course after a
      series of S-turns.

             (11)  Flight at low airspeeds with the airspeed indicator
      covered.  Use various flap settings and distractions.

          b.  Departure Stall.

              (1)  At a safe altitude, have the student attempt
      coordinated power-on (departure) stalls straight ahead and in
      turns.  Emphasize how these stalls could occur during takeoff.

              (2)  Ask the student to demonstrate a power-on
      (departure) stall and distract him/her just before the stall
      occurs.  Explain any effects the distraction may have had on the
      stall or recovery.

          c.  Engine Failure in a Climb Followed by a 180-Degree Turn.
      This demonstration will show the student how much altitude the
      airplane loses following a power failure after takeoff and during
      a 180-degree turn back to the runway and why returning to the
      airport after losing an engine is not a recommended procedure.
      This can be performed using either a medium or steep bank in the
      180-degree turn, but emphasis should be given to stall avoidance.

              (1)  Set up best rate of climb (V sub y).

              (2)  Reduce power smoothly to idle as the airplane passes
      through a cardinal altitude.

              (3)  Lower the nose to maintain the best glide speed and
      make a 180-degree turn at the best glide speed.

              (4)  Point out the altitude loss and emphasize how
      rapidly airspeed decreases following a power failure in a climb
      attitude.
             d.  Cross Controlled Stalls in Gliding Turns.  Perform stalls
      in gliding turns to simulate turns from base to final.  Perform
      the stalls from a properly coordinated turn, a slipping turn, and
      a skidding turn.  Explain the difference between slipping and
      skidding turns.  Explain the ball indicator position in each turn
      and the aircraft behavior in each of the stalls.

          e.  Power off  (Approach-To-Landing) Stalls.

              (1)  Have the student perform a full-flap, gear extended,
      power-off stall with the correct recovery and cleanup procedures.
      Note the loss of altitude.

              (2)  Have the student repeat this procedure and distract
      the student during the stall and recovery and note the effect of
      the distraction.  Show how errors in flap retraction procedure
      can cause a secondary stall.

          f.  Stalls During Go-Arounds.

              (1)  Have the student perform a full-flap, gear extended,
      power-off stall, then recover and attempt to climb with flaps
      extended.  If a higher than normal climb pitch attitude is held,
      a secondary stall will occur.  (In some airplanes, a stall will
      occur if a normal climb pitch attitude is held.)

              (2)  Have the student perform a full-flap, gear extended,
      power-off stall, then recover and retract the flaps rapidly as a
      higher than normal climb pitch attitude is held.  A secondary
      stall or settling with a loss of altitude may result.

          g.  Elevator Trim Stall.

              (1)  Have the student place the airplane in a landing
      approach configuration, in a trimmed descent.

              (2)  After the descent is established, initiate a
      go-around by adding full power, holding only light elevator and
      right rudder pressure.

              (3)  Allow the nose to pitch up and torque to swerve the
      airplane left.  At the first indication of a stall, recover to a
      normal climbing pitch attitude.

              (4)  Emphasize the importance of correct attitude
      control, application of control pressures, and proper trim during
      go-arounds.
   
                     CHAPTER 3.  FLIGHT TRAINING - SPINS

      13.  SPIN TRAINING.  Spin training is required for flight
      instructor-airplane and flight instructor-glider applicants only.
      Upon completion of the training, the applicant's logbook or
      training record should be endorsed by the flight instructor who
      provided the training.  A sample endorsement of spin training for
      flight instructor applicants is available in AC 61-65,
      Certification:  Pilots and Flight Instructors, current edition.

          a.  Spin training must be accomplished in an aircraft that is
      approved for spins.  Before practicing intentional spins, the AFM
      or POH should be consulted for the proper entry and recovery
      techniques.

          b.  The training should begin by practicing both power-on and
      power-off stalls to familiarize the applicant with the aircraft's
      stall characteristics.  Spin avoidance, incipient spins, and
      actual spin entry, spin, and spin recovery techniques should be
      practiced from an altitude above 3,500 feet AGL.

          c.  Spin avoidance training should consist of stalls and
      maneuvering during slow flight using realistic distractions such
      as those listed in Chapter 2.  Performance is considered
      unsatisfactory if it becomes necessary for the instructor to take
      control of the aircraft to avoid a fully developed spin.

          d.  Incipient spins should be practiced to train the
      instructor applicant to recover from a student's poorly performed
      stall or unusual attitude that could lead to a spin.

              (1)  Configure the aircraft for a power-on or power-off
      stall, and continue to apply back elevator pressure.  As the
      stall occurs, apply right or left rudder and allow the nose to
      yaw toward the stalled wing.  Release the spin inducing controls
      and recover as the spin begins by applying opposite rudder and
      forward elevator pressure.  The instructor should discuss control
      application in the recovery.

          e.  Spin entry, spin, and spin recovery should be
      demonstrated by the instructor and repeated, in both directions,
      by the applicant.

              (1)  Apply the entry procedure for a power-off stall.  As
      the airplane approaches a stall, smoothly apply full rudder in
      the direction of desired spin rotation and continue to apply back
      elevator to the limit of travel.  The ailerons should be neutral.
   
              (2)  Allow the spin to develop, and be fully recovered no
      later than one full turn.  Observe the airspeed indicator during
      the spin and subsequent recovery to ensure that it does not reach
      the red line (V sub NE).

              (3)  Follow the recovery procedures recommended by the
      manufacturer in the AFM or POH.  In most aircraft, spin recovery
      techniques consist of retarding power (if in a powered aircraft),
      applying opposite rudder to slow the rotation, neutralizing the
      ailerons, applying positive forward-elevator movement to break
      the stall, neutralizing the rudder as the spinning stops, and
      returning to level flight.


                     CHAPTER 4.  AIRWORTHINESS STANDARDS

      14.  OPERATING LIMITATIONS.  Operating limitations are imposed
      for the safety of pilots and their passengers.  Operations
      contrary to these restrictions are a serious compromise of
      safety.  It is, therefore, most important that all pilots, flight
      and ground instructors, and pilot examiners apply the following
      information on spinning to pilot training and flight operations.

          a.  Normal Category.  Single-engine normal category airplanes
      are placarded against intentional spins.  However, to provide a
      margin of safety when recovery from a stall is delayed, these
      airplanes are tested during certification and must be able to
      recover from a one-turn spin or a 3-second spin, whichever takes
      longer, in not more than one additional turn with the controls
      used in the manner normally used for recovery.  In addition:

              (1)  For both the flaps-retracted and flaps-extended
      conditions, the applicable airspeed limit and positive limit
      maneuvering load factor may not be exceeded.  For the flaps-
      extended condition, the flaps may be retracted during recovery;

              (2)  There may be no excessive back pressure during the
      spin recovery; and

              (3)  It must be impossible to obtain uncontrollable spins
      with any use of the controls.
              ______________________

      Note:  Since airplanes certificated in the normal category have
      not been tested for more than a one-turn or 3-second spin, their
      performance characteristics beyond these limits are unknown.
      This is the reason they are placarded against intentional spins.
   
              ______________________

          b.  Acrobatic Category.  An acrobatic category airplane must
      meet the following requirements.

              (1)  The airplane must recover from any point in a spin,
      in not more than one and one-half additional turns after normal
      recovery application of the controls.  Prior to normal recovery
      application of the controls, the spin test must proceed for six
      turns or 3 seconds, whichever takes longer, with flaps retracted,
      and one turn or 3 seconds, whichever takes longer, with flaps
      extended.  However, beyond 3 seconds, the spin may be
      discontinued when spiral characteristics appear with flaps
      retracted.

              (2)  For both the flaps-retracted and flaps-extended
      conditions, the applicable airspeed limit and the positive limit
      maneuvering load factor may not be exceeded.  For the flaps-
      extended condition, the flaps may be retracted during recovery,
      if a placard is installed prohibiting intentional spins with
      flaps extended.

              (3)  It must be impossible to obtain uncontrollable spins
      with any use of the controls.

              ______________________

      Note:  Since airplanes certificated in the acrobatic category
      have not been tested for more than six turns or 3 seconds, their
      performance characteristics beyond these limits are unknown.

              ______________________

          c.  Utility Category.  A utility category airplane must meet
      the requirements for either the normal or acrobatic category.

      15.  PLACARDS.  Under FAR Section 23.1567, all airplanes type
      certificated under FAR Part 23 must have a flight maneuver
      placard containing the following information:

          a.  For normal category airplanes, there must be a placard in
      front of and in clear view of the pilot stating:  "No acrobatic
      maneuvers, including spins, approved."

          b.  Additionally, for those utility category airplanes, with
      a certification basis after March 1978 and that do not meet the
      spin requirements for acrobatic category airplanes, there must be
         an additional placard in clear view of the pilot stating:  "Spins
      Prohibited."

          c.  For acrobatic category airplanes, there must be a placard
      in clear view of the pilot listing the approved acrobatic
      maneuvers and the recommended entry airspeed for each.  If
      inverted flight maneuvers are not approved, the placard must
      include a notation to this effect.

      16.  PILOT AWARENESS.  The pilot of an airplane placarded against
      intentional spins should assume that the airplane may become
      uncontrollable in a spin.  In addition, stall warning devices
      should not be deactivated for pilot certification flight tests in
      airplanes for which they are required equipment. 
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