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of change of the C$_{L}$ is much less at higher AOA at the root chord. Therefore, an increase in AOA for the wing results in the tips creating a greater proportion of the lift and moving the center of lift behind the CG, creating a negative pitching moment to lower the nose at high AOA. 

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Based on the same principle, when the wing AOA is lowered below the trim position, the tip chords’ C$_{L }$decreases more than the root chord and the center of lift for the wing moves forward creating a positive moment to raise the nose at lower AOA. 

In situations where the pilot is flying in severe/extreme turbulence, wind sheer, or the pilot is exceeding the limitations of the aircraft, the WSC aircraft can get into a situation where the root chord is at a negative AOA and not producing lift. This could result in an emergency vertical dive situation, as discussed later in the Whip Stall-Tuck-Tumble section. When at very low angles or negative angles of attack, the WSC wing is designed so that the wing has positive stability or a nose- up aerodynamic moment. This is accomplished by a number of different systems (washout struts, sprogs and refl ex lines) further explained in chapter 3 that simply keep the trailing edge of the wing up in an emergency low/negative AOA dive situation. As shown in Figure 2-29,  the root area of the wing has reflex which creates a positive pitching moment for the root chord to rotate the nose up towards a level fl ying attitude. At the same time, the tips are at a negative AOA producing lift in the opposite direction as usual, creating a moment to bring the nose/root chord up to a positive AOA to start producing lift and raising the nose to a normal fl ight condition. The negative lift or downward force as produced at the tips and root as shown provide a positive moment to raise the nose back to a normal fl ying attitude. 

