A load factor is the ratio of the total air load acting on the  glider to the gross weight of the glider. A glider in flight with  a load factor of one does not mean the glider is accelerating;  it means the lift on the aircraft is the same as in straight- and-level flight. Load factor may be positive or negative,  dependent on the current flightpath. A load factor of three means that the total load on a glider’s  structure is three times its gross weight. Gravity load factors  are usually expressed in terms of “G”—that is, a load factor  of three may be spoken of as three Gs, or a load factor of  four as four Gs. A load factor of one, or 1 G, represents  conditions in straight-and-level flight, in which the lift is  equal to the weight. Therefore, two Gs would be two times  the normal weight. Gliders may be designed to withstand  stress of up to nine Gs. It is interesting to note that in subjecting a glider to three Gs  in a pullup from a dive, the pilot is pressed down into the  seat with a force equal to three times the person’s weight.  Thus, an idea of the magnitude of the load factor obtained in  any maneuver can be determined by considering the degree  to which the pilot is pressed down into the seat. Since the  operating speed of modern gliders has increased significantly,  this effect has become so pronounced that it is a primary  consideration in the design of the structure for all gliders. If attempting to improve turn performance by increasing  angle of bank while maintaining airspeed, pay close attention  to glider limitations due to the effects of increasing the load  factor. Load factor is defined as the ratio of the load supported  by the glider’s wings to the actual weight of the aircraft and  its contents. A glider in stabilized, wings-level flight has a  load factor of one. Load factor increases rapidly as the angle  of bank increases due to increase wing loading.  [Figure 3-27] With the structural design of gliders planned to withstand  only a certain amount of overload, knowledge of load factors  has become essential for all pilots. Load factors are important  to the pilot for two distinct reasons: In a turn at constant speed, the AOA must be increased to  furnish the extra lift necessary to overcome the centrifugal  force and inertia opposing the turn. As the bank angle  increases, AOA must also increase to provide the required lift.  The result of increasing the AOA is a stall when the critical  AOA is exceeded in a turn.  [Figure 3-28] The amount of horizontal distance an aircraft uses to complete  a turn is referred to as the radius of turn. The radius of turn  at any given bank angle varies directly with the square of the  airspeed. Therefore, if the airspeed of the glider were doubled,  Rate of turn refers to the amount of time it takes for a glider  to turn a specified number of degrees. If flown at the same  airspeed and angle of bank, every glider turns at the same  rate. If airspeed increases and the angle of bank remains  the same, the rate of turn decreases. Conversely, a constant  airspeed coupled with an angle of bank increase results in a  higher rate of turn. 3-14 Radius of Turn Rate of Turn Figure 3-28.  The loads placed on a glider increase as the angle of  bank increases. Figure 3-27.  A glider’s stall speed increases as the bank angle  increases. For example, a 60° angle of bank causes a 40 percent  increase in the glider’s stall speed. 180 160 140 120 100 80 60 40 20 0 Percentage increase in stall speed Angle of bank (degrees) 0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100° 9 8 7 6 5 4 3 2 1 0 Load factor (Gs) Angle of bank (degrees) 0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100° 1.  It is possible for a pilot to impose an obviously  dangerous overload on the glider structures. 2.  Increased load factor increases the stalling speed,  making stalls possible at seemingly safe flight speeds  due to increased wing loading.