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Aerodynamic, also known as “wetted”, exterior surfaces of aircraft can experience significant manufacturing tolerance variations during component fit-up. If gaps at faying edges (i.e. fastening joints) are fixed and/or locked in place with contoured fillers or shims, resulting variations can create turbulent air flows which may create erosion of aft joint surfaces. When the components are formed of composite materials, the erosion may actually produce delamination. As a result, special care must be taken in the manufacture of faying edges of wetted aircraft components at risk for erosion damage.Such risks may be somewhat greater for certain thin-walled curvilinear aircraft components, including engine nacelle lipskins, leading edges of wings, and wetted areas aft of fuselage joints. To avoid critical damage, such thin-walled structures including the noted nacelle lipskins, for example, have been fitted with shims for assuring desired positioning of the thin-walled structures on underlying support structures such as bulkheads.

Methods of applying the shims, generally referred to as “shimming”, have traditionally required relatively tedious efforts to achieve desired levels of precision. Generally, custom contoured shims have been employed, even though applications of the latter have tended to be expensive and time-consuming.

Thus, there has been a continuing need to develop less expensive and more time-saving shimming methods and systems.

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