Next, connect the outer “N” struts to the left and right sections  of the lower wing. Now, the upper wing can be attached and  the flying wires installed. The slave struts can be installed  and the ailerons connected using the same alignment and  adjustment procedures used for the elevator and rudder. The  incidence angle can be checked, as shown in  Figure 2-100 . Once this point is reached, it is a matter of measuring,  checking angles, and adjusting the various components to  obtain the overall aircraft symmetry and desired alignment,  as shown in  Figure 2-96 . Also, remember that care should be used when tightening  the wing wires because extra stress can be inadvertently  induced into the wings. Always loosen one wire before  tightening the opposite wire. Flying and landing wires are  typically set at about 600 pounds and tail brace wires at  about 300 pounds of tension.  When convinced the aircraft is properly rigged, move away  from it and take a good look at the finished product. Are the  wings symmetrical? Does the dihedral look even? Is the tail  section square with the fuselage? Are the wing attaching  hardware, flying wires, and control cables safetied? And  the final task, before the first flight, is to complete the  maintenance record entries.  As with any aircraft maintenance or repair, the instructions  and specifications from the manufacturer, or the procedures  and recommendations found in the construction plans, should  be the primary method to perform the assembly and rigging  of the aircraft. The purpose of an aircraft inspection program is to ensure that  the aircraft is airworthy. The term airworthy is not defined  in the 14 CFR. However, case law relating to the term and  regulations for the issuance of a standard airworthiness  certificate reveal two conditions that must be met for the  aircraft to be considered airworthy:  When flight hours and calendar time are accumulated into  the life of an aircraft, some components wear out and others  deteriorate. Inspections are developed to find these items, and  repair or replace them before they affect the airworthiness  of the aircraft. To establish conformity of an aircraft product, start with a  TCDS. This document is a formal description of the aircraft,  the engine, or the propeller. It is issued by the Federal  Aviation Administration (FAA) when they find that the  product meets the applicable requirements for certification  under 14 CFR. The TCDS lists the limitations and information required  for type certification of aircraft. It includes the certification  basis and eligible serial numbers for the product. It lists  airspeed limits, weight limits, control surface movements,  engine make and models, minimum crew, fuel type, etc.; the  horsepower and rpm limits, thrust limitations, size and weight  for engines; and blade diameter, pitch, etc., for propellers.  2-59 Figure 2-100.  Checking incidence. Aircraft Inspection Purpose of Inspection Programs  Perform an Airframe Conformity and  Airworthiness Inspection 2.  The aircraft must be in a condition for safe operation.  This refers to the condition of the aircraft relative to  wear and deterioration (e.g., skin corrosion, window  delamination/crazing, fluid leaks, and tire wear  beyond specified limits). 1.  The aircraft must conform to its type design or  properly altered condition.  Conformity to type design  is considered attained when the aircraft configuration  and the components installed are consistent with  the drawings, specifications, and other data that are  part of the TC, which includes any supplemental  type certificate (STC) and field approved alterations  incorporated into the aircraft. Wing Incidence angle Measurement for  angle of incidence Use straight edge for flat  bottom airfoils (clark Y  series, etc.) 1 Bevel protractor Plywood Chord line Make bottom parallel with chord line Make rib template to measure incidence of acrobatic type wings Aircraft must be level when checking incidence Straight edge Level aircraft Chock wheels Spirit level 2