“Enhanced Corrosion Protection for the H-60 Helicopter” R. Guillemette and R.V. Luchenta
Materials and Process Engineering
Sikorsky Aircraft Corporation
6900 Main Street
Stratford, Connecticut 06601

Corrosion of military air vehicles is a major concern to all service branches. The effects of corrosion include reduced fleet readiness as well as billions of dollars spent annually inspecting for and repairing corrosion related damage.  In the recent years, an emphasis has been placed on including corrosion prevention within the design of an aircraft, rather than as an afterthought.  This design process in corrosion protection has been embraced by Sikorsky Aircraft Engineering, and is evident in two recent model upgrades, the UH-60M and the MH-60S.

Several key areas were identified as major corrosion drivers that, in the past, have contributed to deterioration of H-60 airframe components.  These included the lack of sealing protection of interior faying surfaces and hardware and limited protection of electrical grounding points. This meant early participation at the design level to incorporate changes, rather than applying added finishes to a released drawing.

As an example, past H-60 helicopter models have relied on a large degree of riveted sheet metal components.  By changing many of these assemblies to monolithic high speed machined “hog-outs” it was possible to limit water traps and faying surfaces produced by joining sheet metal, as well as reducing the number of fasteners, which often create dissimilar metal couples.  Furthermore, improvements were also included in the design by utilizing  the latest available technologies into the design, such as cold expanded nutplates and bushings, improved gasketing materials, and next generation corrosion preventative compounds and sealing materials.