Abstract: Methods for making structural shims (220) for the mating assembly of parts, such as for installation between a skin (212) and substructure (214) of an aircraft. The methods include the steps of disposing a hardenable composition (216) into a gap between the first (212) and second parts (214), hardening the hardenable composition to provide a shim pattern (218) that is dimensionally stable, and removing the shim pattern from the gap without damage. The shim pattern can be used to provide a digital model thereof, which can in turn be used to fabricate the structural shim (220).

Abstract: Various embodiments disclosed relate to a shim pattern. The shim pattern includes a release film. The shim pattern further includes a curable composition disposed on the release film. There are various advantages to using the shim pattern disclosed herein. For example, according to various embodiments, the shim pattern can be used to easily produce a model of a gap between two components of an aircraft (e.g., an airplane, helicopter, drone, or spacecraft) that can be used to form a shim to close the gap.

Abstract: Provided are surfacing films that have a surface layer having opposed first and second major surfaces, the first major surface comprising a fluoropolymer surface and the second major surface optionally comprising a nanostructured surface. A printed layer can be disposed on the second major surface and can be at least partially embedded in the nanostructured surface, if present. As a further option, the fluoropolymer surface can be microreplicated to provide a frictional surface and/or provide aerodynamic drag reduction on aircraft structures. Optionally, the delamination peel strength of the surface layer from the remaining layers can be greater than the tensile strength of the surface layer.

Abstract: Provided are aerodynamic articles and related methods that use an aerodynamic body with a microstructured surface thereon. The microstructured surface has a plurality of parallel primary ridges defining major capillary channels, and optionally a plurality of parallel secondary ridges having a height less than that of the primary ridges and extending between and generally parallel to the primary ridges. The optional secondary ridges at least partially define two or more minor capillary channels within each major capillary channel. The aerodynamic surface provides reduced drag and is capable providing a high degree of friction against shoe surfaces under oil and water contaminated conditions.