Chapter 4: Small Unmanned Aircraft Loading  Figures 4-2  and 4-3 show that banking an aircraft greater than 72° in a steep turn produces a load  factor of 3, and the stalling speed is increased significantly. If this turn is made in an aircraft with a  normal unaccelerated stalling speed of 45 knots, the airspeed must be kept greater than 75 knots to  prevent inducing a stall. A similar effect is experienced in a quick pull up or any maneuver producing  load factors above 1 G. This sudden, unexpected loss of control, particularly in a steep turn or  abrupt application of the back elevator control near the ground, has caused many accidents. Since the load factor is squared as the stalling speed doubles, tremendous loads may be imposed on  structures by stalling an aircraft at relatively high airspeeds.  Compliance with the weight and balance limits of any aircraft is critical to flight safety. Operating  above the maximum weight limitation compromises the structural integrity of an aircraft and adversely  affects its performance. Operation with the center of gravity (CG) outside the approved limits results in  control difficulty. The aircraft’s weight and balance data is important information for a pilot that must  be frequently reevaluated.  Weight is the force with which gravity attracts a body toward the center of the Earth. It is a product  of the mass of a body and the acceleration acting on the body. Weight is a major factor in aircraft  construction and operation and demands respect from all pilots. The force of gravity continuously  attempts to pull an aircraft down toward Earth. The force of lift is the only force that counteracts  weight and sustains an aircraft in flight. The amount of lift produced by an airfoil is limited by the  airfoil design, AOA, airspeed, and air density. To assure that the lift generated is sufficient to  counteract weight, loading an aircraft beyond the manufacturer’s recommended weight must be  avoided. If the weight is greater than the lift generated, the aircraft may be incapable of flight.  Remote Pilot – Small Unmanned Aircraft Systems Study Guide  32  Weight Control  Weight and Balance Figure 4-3.  Load factor changes stall speed.