Trim in the Stall
Trim is not normally used to relieve pressure during the actual performance of training stalls. However the new PTS (Practical Test Standards) now calls for stalls to be made in a trimmed condition with distractions. A no power recovery should occasionally be called for. Any flaps more than 20 degrees should be taken off at once. Less than 20 degrees of flaps should come off when climb speed is attained. The apparent attitude of stalled aircraft with flaps is quite flat. Holding pitch attitude of the aircraft correctly while removing flaps is a must. No loss of altitude should occur while removing flaps. A secondary stall during recovery is indicative of failure.

Wings in the Stall
The manner in which the stall cues are transmitted is dependent upon wing shape, twist (washin/washout) and installed features such as strips, slots or flaps. Together these cues provide the pilot a warning of the stall onset. With washout the wing is mounted in a jig and twisted to lower the angle of incidence at the wing tip while being built.. Impact air on the bottom of the wing still provides some residual lift but not enough to keep the airplane flying.

Ailerons in the stall will only aggravate it. Ailerons change to chord line of the wing to create lift and movement along the roll axis. When the aileron is stalled, their movement causes roll that is contrary to what you either want or expect. Once the recovery is initiated with forward yoke and rudder the use of ailerons may or may not be helpful depending on the aircraft. This difference is aileron effectiveness is related to the washin/washout or twist given to the wing progressively toward the tips. Tips stall last and recover first in most modern aircraft due to a decreased angle of incidence. Aircraft design determines the aircraft stall characteristics.

A stall progression, if the same on both wings, will result in a straight ahead nose drop with no rotation about the roll axis. Not all stalls are symmetrical and the pilot will experience an abrupt drop of one wing or the other. The instinctive reaction to this by the inexperienced will be a reaction to lift the fallen wing by using the aileron. WRONG! Only the rudder can effectively stop the rolling of the aircraft. The falling wing can be decisively raised only with opposite rudder. This rudder causes the falling wing to increase in speed by moving forward. You may still be stalled but the rotation was caused by a non-symmetrical stall. Rudder can make the stall symmetrical without the rolling.

When the angle of attack reaches a certain point the drag is so great that full power will be inadequate to maintain altitude. At this point you are flying 'behind the power curve'. In this condition your only recourse is to sacrifice altitude by lowering the nose. Without sufficient altitude to allow the aircraft to resume unstalled flight, this is not a viable option. This is the flight situation that arrives in entry to a full-power-on stall. With power full and stalled any misuse of the rudder or ailerons will precipitate a relatively quick spin entry.

Rudder in the stall
A spin can be prevented even when aggravated by the ailerons if the pilot maintains directional control through use of the rudder. A spin can only occur with the addition of yaw in the stall. The rudder can and should be used to prevent any yaw in the stall and the recovery procedure. The correct use of rudder in stalls is essential. The rudder controls the yaw which means it can keep the speed of each wing the same or cause one to be ahead (faster) than the other. The slower wing will stall first and drop. Any effort to raise the wing with aileron will add drag and deepen the wing's stall.

The rudder is the last control to lose effectiveness. Even in the stall if there is some forward momentum there is some degree of effectiveness. In a stall entry you first lose aileron control, then elevator and lastly rudder. On recovery, you gain rudder control first then elevator and lastly aileron. As the most effective control during slow speed maneuvers rudder, correctly applied, can compensate for the lost effectiveness of the ailerons. The rudder can be used to keep the wings level to the relative wind. Such level wings causes the stall break to be without a wing dropping. Keeping the ball of the inclinometer in the center gives assurance that the tail is following the nose. This is coordinated flight. If the heading indicator is held steady with a very gradual application of right rudder, little or no aileron movement will be required to keep wings level.

First Stall Instruction (Instructor)
A student pilot's introduction to stalls will imprint his entire flying career. Practically everything written on stalls is inductive to terror. If the first stall is abrupt, violent, and with sharp wing drop every instinctive reaction will aggravate and prolong the student terror. Instead, the instructor should put the student in charge and begin a slow smooth gentle entry with rudder control closely monitored by the instructor. Very gradually over the entire training period the stalls may/should be aggravated. The student introduction to turbulence and weather should be just as gradual both as to duration and severity. The better a pilots knowledge of wind and weather patterns the better able he will be to select desirable conditions. There is nothing wrong with not enjoying either stalls or turbulence.

Stalls should be introduced on the second flight.... gently. After clearing turns expose the student to the nose drop that occurs on power reduction. Repeat the power reduction and have the student hold the nose level with the yoke. Have the student apply carburetor heat and reduce the power to off while holding the nosed to prevent loss of altitude. The yoke movement should initially be very gradual and increase logarithmically as speed decreases. The last few inches of yoke movement should be UP and back.

The recovery must be positive in reducing the angle of attack but not more than required to lower the nose to or slightly below the horizon. The abruptness of the recovery should be in direct proportion to the abruptness of the stall. Any recovery action in excess of what is needed to return the wing to an effective angle of attach can only delay the recovery and cause an excessive lost of altitude. At the same time, full power is applied to increase speed and thereby reduce the angle of attack. Some aircraft have sufficient power to literally fly out of a stall. The final recovery is to resume coordinated use of the flight controls.

Proficiency stalls are those stalls expected of the pilot applicants. Included in stall training will be such demonstration stalls as the accelerated stall and the oscillation stall which are not required except for flight instructor tests. Demonstration stalls are not part of the PTS but should be taught and demonstrated since they can occur when you least expect them.

Stall Lesson
Introduce this lesson in slow cruise where you allow the student to look to the wing tips and note that the rudder can be used to make one wing move forward of the other. Knowing this, advise the student that in a stall he should always step on the high wing. Oscillation stalls are performed in a power-off and clean configuration. The yoke is continuously held back from a gentle and smooth entry. The rudder is used to raise any wing that should drop and start a roll. Always step on the high wing. In a stall use full rudder with rapid movement to catch a falling wing before it gets down too far. Hold the yoke level to cockpit.

PTS Stalls
PTS wants 20-degree banks for power-on stalls and up to 30 degrees for power-off stalls. The stall recovery puts the nose on or very slightly below the horizon. The pilot applies full power and corrects for any stall-induced roll with the rudder.

Objectives of Stall Instruction
The objective of stall practice is to develop awareness of the mechanical and physiological cues that precede the stall along with the appropriate reactions to effect recovery. We practice intentional stalls so that we can react appropriately to the consistency and predictability of a given aircraft. Instinctive control reactions are both wrong and potentially dangerous. Modern aircraft have opposite ailerons with differential travel to reduce but not prevent the dangerous aspects of improper or inappropriate aileron movements.  Appropriate reaction requires coordinated use of the rudder and forward elevator to reduce the angle of attack. Even the best combinations of these features can be offset by weather (icing), weight, loading and power. The more violently a stall is entered the more violent will be its break. Recognizing the sight, sound and touch of a stall entry is to be followed by an immediate reduction of pitch attitude.

There are three purposes for instruction in stalls, none of which have to do with the actual stall performance:
--We want a pilot to be familiar with the flight conditions most likely to precipitate a stall. --The second objective in stall instruction is for the pilot to become familiar with the sight, sound and feel of an approaching stall. 
--The third, and last purpose, is that the pilot take immediate and proper corrective action.

Knowing where stalls are likely to occur is the second awareness objective of practicing stalls. By practicing a variety of stalls at altitude you learn enough about your aircraft to know how much forward yoke movement is required for recovery along with how much altitude is required. The availability of power makes a significant difference in the recovery attitude and procedure. Remember that your right leg and foot use accompany applying power to prevent yaw.  Some aircraft have sufficient power to effectively fly out of the stall; others do not. Know your airplane.

The reason for doing training stalls is to help the pilot overcome the dangerous instinctive reactions and to initiate an immediate stall recovery based on 'knowing' what to do. Proximity to the ground is an inhibiting factor that must be overcome. Regardless of altitude the elevator control must be moved forward to reduce the angle of attack, only then can the stall recovery be initiated.

Clearing Turns
There are certain aspects of training stalls that are the same for all of them. Every stall should (must) be preceded by 90 degree clearing turns left and right. (The clearing turns should be as precise as to amount of turn, angle of bank, altitude, and heading as though they were part of the stall process.) The well performed practice stall will result in an initial loss of 100'. The actual stall may be called as incipient, partial, full, or aggravated. The longer a stall is aggravated or held, the more airspeed decreases. This means either more power or altitude will be required during recovery. The recovery is always with full power, no flaps, in a climb, and at best rate of climb speed (65 kts). An old FAA recommendation was that 300' be gained during recovery but the time required is not practical in many cases. Trim for any climb.

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