high AOA on that wing might cause the airplane to yaw in that direction. This adverse yaw could result in a spin unless directional control were maintained by rudder and/or aileron control is sufficiently reduced. 

Even though excessive aileron pressure may have been applied, a spin does not occur if directional (yaw) control is maintained by timely application of coordinated rudder pressure. Therefore, it is important that the rudder be used properly during both entry and recovery from a stall. The primary use of the rudder in stall recovery is to counteract any tendency of the glider to yaw. The correct recovery technique would be to decrease the pitch attitude by applying forward elevator pressure to reduce the AOA while simultaneously maintaining directional control with coordinated use of the aileron and rudder. 

Due to engineering design variations, the stall characteristics for all gliders cannot be specifically described; however, the similarities found in gliders are noteworthy enough to be considered. The factors that affect the stalling characteristics of the glider are weight and balance, bank and pitch attitude, coordination, and drag. The pilot should learn the stall characteristics of the glider being flown and the proper correction procedures. It should be reemphasized that a stall can occur at any airspeed, in any attitude, or at any power setting in the case of a self-launching or sustaining glider, depending on the total value of factors affecting the particular glider. 

Whenever practicing stalls while turning, a constant bank angle should be maintained until the stall occurs. After the stall occurs, coordinated control inputs should be made to return the glider to wings-level flight. 

Advanced stalls include secondary, accelerated, and crossed- control stalls. These stalls are extremely useful for pilots to expand their knowledge of stall/spin awareness. 

## Secondary Stalls 

A secondary stall occurs after a recovery from a preceding stall. It is caused by attempting to hasten the completion of a stall recovery with abrupt control input before the glider has regained sufficient flying speed and the critical AOA is again exceeded. When this stall occurs, the back-elevator pressure should again be released as in a normal stall recovery. When sufficient airspeed has been regained, the glider can then be returned to wings-level, straight flight. 

## Accelerated Stalls 

Although the stalls already discussed normally occur at a specific airspeed, the pilot must thoroughly understand that all stalls result solely from attempts to fly at excessively high 

angles of attack. During flight, the AOA of a glider wing is determined by a number of factors, the most important of which are airspeed, gross weight of the glider, and load factors imposed by maneuvering. 

At gross weight, the glider consistently stalls at the same indicated airspeed if no acceleration is involved. However, the glider stalls at a higher indicated airspeed when excessive maneuvering loads are imposed by steep turns, pull-ups, or other abrupt changes in its flightpath. Stalls entered from such flight situations are called “accelerated maneuver stalls, a term that has no reference to the airspeeds involved. Stalls that result from abrupt maneuvers tend to be more rapid or severe than the unaccelerated or steady state stall. Accelerated stalls occur at higher-than-normal airspeeds and may be unexpected by pilots. These accelerated stalls result when the AOA exceeds the angle necessary to stall the airflow over the wing. The relative wind angle increases as the loads on the wings require more lift to change direction, either vertically or horizontally, and inertia pushes the wings into the airmass resulting in an increased AOA. Depending on the wing configuration and quality of coordination, one wing may stall prior to the other wing resulting in a wingover entry into a spiral or spin. If the wings have a slight or pronounced sweep, one wing can easily develop more lift than the other wing almost instantaneously resulting in a wingover before the pilot can react. This is the common killer scenario of a pilot turning too tightly in the traffic pattern and crashing upside down. 

Accelerated maneuver stalls should not be performed in any glider in which this maneuver is prohibited by the GFM/ POH. If they are permitted, they should be performed with a bank of approximately 45° and never at a speed greater than the glider manufacturer’s recommended airspeeds or the design maneuvering speed specified for the glider. The design maneuvering speed is the maximum speed at which the glider can be stalled or the application of full aerodynamic control will not exceed the glider’s limit load factor. At or below this speed, the glider is designed so that it stalls before the limit load factor can be exceeded. The objective of demonstrating accelerated stalls is not to develop competency in setting up the stall, but rather to learn how they may occur and to develop the ability to recognize a prestall situation immediately and then take the proper recovery action. It is important that recovery is made at the first indication of a stall, or immediately after the stall has fully developed; a prolonged stall condition should never be allowed. 

A glider stalls during a coordinated turn as it does from straight flight, except the pitching and rolling actions tend to be more sudden. If the glider is slipping toward the inside of the turn at the time the stall occurs, it tends to roll rapidly 

