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. 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. 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. 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.  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  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  Secondary Stalls Accelerated Stalls 7-34