Chapter Summary Components and systems consist of two primary  subassemblies: wing and carriage. The main wing component  is the frame, which is composed of the leading edges, keel,  crossbar, and control frame. The typical wing frame has lower  wires and upper wires with a king post. The strutted version  has wing struts and no upper rigging. The frame is designed  so the outboard leading edges flex, and it also has a control  system that allows the keel to move side to side relative to the  leading edges for roll control. The sail is designed specifi cally  for the frame with battens and leading edge stiffner provide  the rigid airfoil shape of the sail. The carriage is separate from the wing. Different wings can be  put on the same carriage at separate times for different types  of flying (example: large wing is used for flying low and slow  where a small wing can be used for flying fast and long cross- country missions). As discussed in Chapter 2, Aerodynamics,  each wing must be approved by the manufacturer to go on  a specifi c carriage. Main carriage components are the mast, carriage keel, front  tube, and engine mount. This structure houses the fl ight deck,  powerplant, and landing gear. The carriage structure also  houses system components such as the electrical system,  ballistic parachute, and fuel tank. The flight deck is the heart  of the carriage providing pilot systems for communications,  navigation, engine/flight/navigation instruments, and  electrical controls. 3-22