Relative Wind Flightpath Trailing edge at center  of wing held up by  reflex lines. Reflex lines used to hold up the  trailing edge Aerodynamic force at tips Wing root at negative AOA producing no lift Trailing edge of tips  held up with washout  struts at negative  angle of attack Tip moment arm -L$_{T}$ Reflex force moment arm Reflex in  airfoil creates  force near  trailing edge  of root area Positive moment caused by aerodynamic force at tips plus reflex in  airfoil at root -L$_{R}$ Relative Wind Reflex Dihedral from wing flex Anhedral built into frame Figure 2-30. Wing front view example showing anhedral in the  middle of the wing and dihedral at the outboard section of the wing  because of leading edge flex. Figure 2-29. Emergency vertical dive recovery for a WSC wing.  As described in the Pilot’s Handbook of Aeronautical  Knowledge, more dihedral or less anhedral in a WSC wing  creates more roll stability. More roll stability might be helpful  for a training wing or a fast wing made for long cross-country  straight flight, but most pilots want a balance between roll  stability and the ability to make quicker turns and a sport  car feel for banking/turning. Therefore, a balance between  the stability and the instability is achieved through anhedral  plus other important wing design features such as nose angle,  twist, and airfoil shape from root to tip. An aerodynamic characteristic of swept wings is an “effective  dihedral” based on the sweep of the wing and angle of attack.  The combination of the physical anhedral in the wing and the  effective dihedral due to wing sweep provides the balance of  stability and rolling moments for a particular wing design. The design of the wing can have actual dihedral or anhedral in  the wing. Even with anhedral designed in the inboard section  of the wing, the outboard sections of the wing could have  some dihedral because of the flex in the outboard leading  edges. As the wing is loaded up from additional weight or  during a turn, the tips flex up more creating more dihedral  and a roll stabilizing effect when loaded.  [Figure 2-30] Reflex also provides a stable pitch up moment for an airfoil  when it is flying at normal flight angles of attack. The greater  the reflex, the greater the nose up moment of the airfoil. This  is used in some WSC airfoil designs and also for trim control  as discussed in Chapter 3. The wing design is the main contributing factor for pitch  stability and moments, but the carriage design can also  influence the pitching moment of the WSC aircraft. For  example, at very high speeds in a dive, a streamlined carriage  would have less drag and, therefore, a greater nose-up moment  because of less drag. The design of the carriage parts can have  an effect on aerodynamic forces on the carriage, resulting in  different moments for different carriage designs. The drag of the wing in combination with the drag of the  carriage at various airspeeds provides a number of pitching  moments, which are tested by the manufacturer—a reason  the carriage is matched to the wing for compatibility. Each  manufacturer designs the carriage to match the wing and takes  into account these unique factors.  Generally, it is thought that the wing remains level and the  weight shifts to the side to initiate a turn. Another way to  look at how the WSC wing rolls is to examine the carriage  and the wing moment from the carriage point of view. For  example, the CG hangs far below a wing weighing  ⅛  of  the carriage weight. When the control bar is moved to the  side, creating a moment about the carriage/wing hang point,  the carriage stays vertical and the wing rotates around the  carriage. Therefore, there are two rolling moments that both  contribute to the WSC rolling into a bank: Overall, the amount of sweep, twist, specifi c airfoil design  from root to the tip, and the carriage design determine the  pitching moments of the WSC aircraft. Some have small  pitching moments, some have greater pitching moments.  Each WSC model is different with a balance of these  aerodynamic parameters to accomplish the specifi c mission  for each unique carriage and wing combination.   Carriage Moments   Pitch Moments Summary  Roll Stability and Moments •  The pilot creating the force on the control bar rotating  the wing about the wing/carriage hang point. 2-16